Search Results

Search found 6169 results on 247 pages for 'jvm languages'.

Page 216/247 | < Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >

  • Efficiency of Java "Double Brace Initialization"?

    - by Jim Ferrans
    In Hidden Features of Java the top answer mentions Double Brace Initialization, with a very enticing syntax: Set<String> flavors = new HashSet<String>() {{ add("vanilla"); add("strawberry"); add("chocolate"); add("butter pecan"); }}; This idiom creates an anonymous inner class with just an instance initializer in it, which "can use any [...] methods in the containing scope". Main question: Is this as inefficient as it sounds? Should its use be limited to one-off initializations? (And of course showing off!) Second question: The new HashSet must be the "this" used in the instance initializer ... can anyone shed light on the mechanism? Third question: Is this idiom too obscure to use in production code? Summary: Very, very nice answers, thanks everyone. On question (3), people felt the syntax should be clear (though I'd recommend an occasional comment, especially if your code will pass on to developers who may not be familiar with it). On question (1), The generated code should run quickly. The extra .class files do cause jar file clutter, and slow program startup slightly (thanks to coobird for measuring that). Thilo pointed out that garbage collection can be affected, and the memory cost for the extra loaded classes may be a factor in some cases. Question (2) turned out to be most interesting to me. If I understand the answers, what's happening in DBI is that the anonymous inner class extends the class of the object being constructed by the new operator, and hence has a "this" value referencing the instance being constructed. Very neat. Overall, DBI strikes me as something of an intellectual curiousity. Coobird and others point out you can achieve the same effect with Arrays.asList, varargs methods, Google Collections, and the proposed Java 7 Collection literals. Newer JVM languages like Scala, JRuby, and Groovy also offer concise notations for list construction, and interoperate well with Java. Given that DBI clutters up the classpath, slows down class loading a bit, and makes the code a tad more obscure, I'd probably shy away from it. However, I plan to spring this on a friend who's just gotten his SCJP and loves good natured jousts about Java semantics! ;-) Thanks everyone!

    Read the article

  • makefile pathing issues on OSX

    - by Justin808
    OK, I thought I would try one last update and see if it gets me anywhere. I've created a very small test case. This should not build anything, it just tests the path settings. Also I've setup the path so there are no spaces. The is the smallest, simplest test case I could come up with. This makefile will set the path, echo the path, run avr-gcc -v with the full path specified and then try to run it without the full path specified. It should find avr-gcc in the path on the second try, but does not. makefile TOOLCHAIN := /Users/justinzaun/Desktop/AVRBuilder.app/Contents/Resources/avrchain PATH := ${TOOLCHAIN}/bin:${PATH} export PATH all: @echo ${PATH} @echo -------- "${TOOLCHAIN}/bin/avr-gcc" -v @echo -------- avr-gcc -v output JUSTINs-MacBook-Air:Untitled justinzaun$ make /Users/justinzaun/Desktop/AVRBuilder.app/Contents/Resources/avrchain/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin -------- "/Users/justinzaun/Desktop/AVRBuilder.app/Contents/Resources/avrchain/bin/avr-gcc" -v Using built-in specs. COLLECT_GCC=/Users/justinzaun/Desktop/AVRBuilder.app/Contents/Resources/avrchain/bin/avr-gcc COLLECT_LTO_WRAPPER=/Users/justinzaun/Desktop/AVRBuilder.app/Contents/Resources/avrchain/bin/../libexec/gcc/avr/4.6.3/lto-wrapper Target: avr Configured with: /Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../gcc/configure --prefix=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --exec-prefix=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --datadir=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --target=avr --enable-languages=c,objc,c++ --disable-libssp --disable-lto --disable-nls --disable-libgomp --disable-gdbtk --disable-threads --enable-poison-system-directories Thread model: single gcc version 4.6.3 (GCC) -------- avr-gcc -v make: avr-gcc: No such file or directory make: *** [all] Error 1 JUSTINs-MacBook-Air:Untitled justinzaun$ Original Question I'm trying to set the path from within the makefile. I can't seem to do this on OSX. Setting the path with PATH := /new/bin/:$(PATH) does not work. See my makefile below. makefile PROJECTNAME = Untitled # Name of target controller # (e.g. 'at90s8515', see the available avr-gcc mmcu # options for possible values) MCU = atmega640 # id to use with programmer # default: PROGRAMMER_MCU=$(MCU) # In case the programer used, e.g avrdude, doesn't # accept the same MCU name as avr-gcc (for example # for ATmega8s, avr-gcc expects 'atmega8' and # avrdude requires 'm8') PROGRAMMER_MCU = $(MCU) # Source files # List C/C++/Assembly source files: # (list all files to compile, e.g. 'a.c b.cpp as.S'): # Use .cc, .cpp or .C suffix for C++ files, use .S # (NOT .s !!!) for assembly source code files. PRJSRC = main.c \ utils.c # additional includes (e.g. -I/path/to/mydir) INC = # libraries to link in (e.g. -lmylib) LIBS = # Optimization level, # use s (size opt), 1, 2, 3 or 0 (off) OPTLEVEL = s ### You should not have to touch anything below this line ### PATH := /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin:/usr/bin:/bin:$(PATH) CPATH := /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/include # HEXFORMAT -- format for .hex file output HEXFORMAT = ihex # compiler CFLAGS = -I. $(INC) -g -mmcu=$(MCU) -O$(OPTLEVEL) \ -fpack-struct -fshort-enums \ -funsigned-bitfields -funsigned-char \ -Wall -Wstrict-prototypes \ -Wa,-ahlms=$(firstword \ $(filter %.lst, $(<:.c=.lst))) # c++ specific flags CPPFLAGS = -fno-exceptions \ -Wa,-ahlms=$(firstword \ $(filter %.lst, $(<:.cpp=.lst)) \ $(filter %.lst, $(<:.cc=.lst)) \ $(filter %.lst, $(<:.C=.lst))) # assembler ASMFLAGS = -I. $(INC) -mmcu=$(MCU) \ -x assembler-with-cpp \ -Wa,-gstabs,-ahlms=$(firstword \ $(<:.S=.lst) $(<.s=.lst)) # linker LDFLAGS = -Wl,-Map,$(TRG).map -mmcu=$(MCU) \ -lm $(LIBS) ##### executables #### CC=avr-gcc OBJCOPY=avr-objcopy OBJDUMP=avr-objdump SIZE=avr-size AVRDUDE=avrdude REMOVE=rm -f ##### automatic target names #### TRG=$(PROJECTNAME).out DUMPTRG=$(PROJECTNAME).s HEXROMTRG=$(PROJECTNAME).hex HEXTRG=$(HEXROMTRG) $(PROJECTNAME).ee.hex # Start by splitting source files by type # C++ CPPFILES=$(filter %.cpp, $(PRJSRC)) CCFILES=$(filter %.cc, $(PRJSRC)) BIGCFILES=$(filter %.C, $(PRJSRC)) # C CFILES=$(filter %.c, $(PRJSRC)) # Assembly ASMFILES=$(filter %.S, $(PRJSRC)) # List all object files we need to create OBJDEPS=$(CFILES:.c=.o) \ $(CPPFILES:.cpp=.o) \ $(BIGCFILES:.C=.o) \ $(CCFILES:.cc=.o) \ $(ASMFILES:.S=.o) # Define all lst files. LST=$(filter %.lst, $(OBJDEPS:.o=.lst)) # All the possible generated assembly # files (.s files) GENASMFILES=$(filter %.s, $(OBJDEPS:.o=.s)) .SUFFIXES : .c .cc .cpp .C .o .out .s .S \ .hex .ee.hex .h .hh .hpp # Make targets: # all, disasm, stats, hex, writeflash/install, clean all: $(TRG) $(TRG): $(OBJDEPS) $(CC) $(LDFLAGS) -o $(TRG) $(OBJDEPS) #### Generating assembly #### # asm from C %.s: %.c $(CC) -S $(CFLAGS) $< -o $@ # asm from (hand coded) asm %.s: %.S $(CC) -S $(ASMFLAGS) $< > $@ # asm from C++ .cpp.s .cc.s .C.s : $(CC) -S $(CFLAGS) $(CPPFLAGS) $< -o $@ #### Generating object files #### # object from C .c.o: $(CC) $(CFLAGS) -c $< -o $@ # object from C++ (.cc, .cpp, .C files) .cc.o .cpp.o .C.o : $(CC) $(CFLAGS) $(CPPFLAGS) -c $< -o $@ # object from asm .S.o : $(CC) $(ASMFLAGS) -c $< -o $@ #### Generating hex files #### # hex files from elf .out.hex: $(OBJCOPY) -j .text \ -j .data \ -O $(HEXFORMAT) $< $@ .out.ee.hex: $(OBJCOPY) -j .eeprom \ --change-section-lma .eeprom=0 \ -O $(HEXFORMAT) $< $@ #### Information #### info: @echo PATH: @echo "$(PATH)" $(CC) -v which $(CC) #### Cleanup #### clean: $(REMOVE) $(TRG) $(TRG).map $(DUMPTRG) $(REMOVE) $(OBJDEPS) $(REMOVE) $(LST) $(REMOVE) $(GENASMFILES) $(REMOVE) $(HEXTRG) error JUSTINs-MacBook-Air:Untitled justinzaun$ make avr-gcc -I. -g -mmcu=atmega640 -Os -fpack-struct -fshort-enums -funsigned-bitfields -funsigned-char -Wall -Wstrict-prototypes -Wa,-ahlms=main.lst -c main.c -o main.o make: avr-gcc: No such file or directory make: *** [main.o] Error 1 JUSTINs-MacBook-Air:Untitled justinzaun$ If I change my CC= to include the full path: CC=/Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin/avr-gcc then it finds it, but this doesn't seem the correct way to do things. For instance its trying to use the system as not the one in the correct path. update - Just to be sure, I'm adding the output of my ls command too so everyone knows the file exist. Also I've added a make info target to the makefile and showing that output as well. JUSTINs-MacBook-Air:Untitled justinzaun$ ls /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin ar avr-elfedit avr-man avr-strip objcopy as avr-g++ avr-nm avrdude objdump avr-addr2line avr-gcc avr-objcopy c++ ranlib avr-ar avr-gcc-4.6.3 avr-objdump g++ strip avr-as avr-gcov avr-ranlib gcc avr-c++ avr-gprof avr-readelf ld avr-c++filt avr-ld avr-size ld.bfd avr-cpp avr-ld.bfd avr-strings nm JUSTINs-MacBook-Air:Untitled justinzaun$ Output of make info with the \ in my path JUSTINs-MacBook-Air:Untitled justinzaun$ make info PATH: /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin avr-gcc -v make: avr-gcc: No such file or directory make: *** [info] Error 1 JUSTINs-MacBook-Air:Untitled justinzaun$ Output of make info with the \ not in my path JUSTINs-MacBook-Air:Untitled justinzaun$ make info PATH: /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR Builder.app/Contents/Resources/avrchain/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin avr-gcc -v make: avr-gcc: No such file or directory make: *** [info] Error 1 JUSTINs-MacBook-Air:Untitled justinzaun$ update - When I have my CC set to include the full path as described above, this is the result of make info. JUSTINs-MacBook-Air:Untitled justinzaun$ make info PATH: /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR Builder.app/Contents/Resources/avrchain/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin/avr-gcc -v Using built-in specs. COLLECT_GCC=/Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR Builder.app/Contents/Resources/avrchain/bin/avr-gcc COLLECT_LTO_WRAPPER=/Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR Builder.app/Contents/Resources/avrchain/bin/../libexec/gcc/avr/4.6.3/lto-wrapper Target: avr Configured with: /Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../gcc/configure --prefix=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --exec-prefix=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --datadir=/Users/justinzaun/Development/AVRBuilder/Packages/gccobj/../build/ --target=avr --enable-languages=c,objc,c++ --disable-libssp --disable-lto --disable-nls --disable-libgomp --disable-gdbtk --disable-threads --enable-poison-system-directories Thread model: single gcc version 4.6.3 (GCC) which /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR\ Builder.app/Contents/Resources/avrchain/bin/avr-gcc /Users/justinzaun/Library/Developer/Xcode/DerivedData/AVR_Builder-gxiykwiwjywvoagykxvmotvncbyd/Build/Products/Debug/AVR Builder.app/Contents/Resources/avrchain/bin/avr-gcc JUSTINs-MacBook-Air:Untitled justinzaun$

    Read the article

  • Spring/RMI server error

    - by 4herpsand7derpsago
    We have a Spring MVC web app (WAR) deploying to Tomcat (6.0.35) that launches a thread inside a separate JVM at deploy time (don't ask why - not my design) and then communicates with that thread via RMI over port 8888. Despite being totally convoluded, this was working perfectly fine up until yesterday, and now the thread is failing at startup and despite our best efforts to add logging into the mix, we are hitting a wall. This is the only exception we are able to find in the logs: Jun 12, 2012 3:11:36 AM com.ourapp.ImageController destroy SEVERE: Shutdown Error: Lookup of RMI stub failed; nested exception is java.rmi.ConnectException: Connection refused to host: localhost; nested exception is: java.net.ConnectException: Connection refused Jun 12, 2012 3:11:37 AM org.apache.catalina.core.StandardContext listenerStop SEVERE: Exception sending context destroyed event to listener instance of class org.springframework.web.context.ContextLoaderListener java.lang.NoClassDefFoundError: org/springframework/web/context/ContextCleanupListener at org.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:80) at org.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:3973) at org.apache.catalina.core.StandardContext.stop(StandardContext.java:4577) at org.apache.catalina.startup.HostConfig.checkResources(HostConfig.java:1165) at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1271) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:296) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119) at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337) at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601) at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610) at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590) at java.lang.Thread.run(Thread.java:662) Caused by: java.lang.ClassNotFoundException: org.springframework.web.context.ContextCleanupListener at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233) ... 12 more The ImageController is the Spring MVC Controller that is responsible for kicking off this daemon/spawned RMI thread. Based on the verbage of this error, does anybody have any idea what might be causing this "connection refused" error? Running a netstat -an | grep 8888 (this is a Linux machine) produces no output which means nothing is listening on that port. Thanks in advance for any ideas/suggestions that lead to a fix. Edit: Here's another ConnectionException we're seeing: Caused by: java.net.ConnectException: Connection refused at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366) at java.net.Socket.connect(Socket.java:529) at java.net.Socket.connect(Socket.java:478) at java.net.Socket.<init>(Socket.java:375) at java.net.Socket.<init>(Socket.java:189) at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22) at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128) at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:595) ... 74 more

    Read the article

  • Java: Reading a pdf file from URL into Byte array/ByteBuffer in an applet.

    - by Pol
    I'm trying to figure out why this particular snippet of code isn't working for me. I've got an applet which is supposed to read a .pdf and display it with a pdf-renderer library, but for some reason when I read in the .pdf files which sit on my server, they end up as being corrupt. I've tested it by writing the files back out again. I've tried viewing the applet in both IE and Firefox and the corrupt files occur. Funny thing is, when I trying viewing the applet in Safari (for Windows), the file is actually fine! I understand the JVM might be different, but I am still lost. I've compiled in Java 1.5. JVMs are 1.6. The snippet which reads the file is below. public static ByteBuffer getAsByteArray(URL url) throws IOException { ByteArrayOutputStream tmpOut = new ByteArrayOutputStream(); URLConnection connection = url.openConnection(); int contentLength = connection.getContentLength(); InputStream in = url.openStream(); byte[] buf = new byte[512]; int len; while (true) { len = in.read(buf); if (len == -1) { break; } tmpOut.write(buf, 0, len); } tmpOut.close(); ByteBuffer bb = ByteBuffer.wrap(tmpOut.toByteArray(), 0, tmpOut.size()); //Lines below used to test if file is corrupt //FileOutputStream fos = new FileOutputStream("C:\\abc.pdf"); //fos.write(tmpOut.toByteArray()); return bb; } I must be missing something, and I've been banging my head trying to figure it out. Any help is greatly appreciated. Thanks. Edit: To further clarify my situation, the difference in the file before I read then with the snippet and after, is that the ones I output after reading are significantly smaller than they originally are. When opening them, they are not recognized as .pdf files. There are no exceptions being thrown that I ignore, and I have tried flushing to no avail. This snippet works in Safari, meaning the files are read in it's entirety, with no difference in size, and can be opened with any .pdf reader. In IE and Firefox, the files always end up being corrupted, consistently the same smaller size. I monitored the len variable (when reading a 59kb file), hoping to see how many bytes get read in at each loop. In IE and Firefox, at 18kb, the in.read(buf) returns a -1 as if the file has ended. Safari does not do this. I'll keep at it, and I appreciate all the suggestions so far.

    Read the article

  • Scala actors: receive vs react

    - by jqno
    Let me first say that I have quite a lot of Java experience, but have only recently become interested in functional languages. Recently I've started looking at Scala, which seems like a very nice language. However, I've been reading about Scala's Actor framework in Programming in Scala, and there's one thing I don't understand. In chapter 30.4 it says that using react instead of receive makes it possible to re-use threads, which is good for performance, since threads are expensive in the JVM. Does this mean that, as long as I remember to call react instead of receive, I can start as many Actors as I like? Before discovering Scala, I've been playing with Erlang, and the author of Programming Erlang boasts about spawning over 200,000 processes without breaking a sweat. I'd hate to do that with Java threads. What kind of limits am I looking at in Scala as compared to Erlang (and Java)? Also, how does this thread re-use work in Scala? Let's assume, for simplicity, that I have only one thread. Will all the actors that I start run sequentially in this thread, or will some sort of task-switching take place? For example, if I start two actors that ping-pong messages to each other, will I risk deadlock if they're started in the same thread? According to Programming in Scala, writing actors to use react is more difficult than with receive. This sounds plausible, since react doesn't return. However, the book goes on to show how you can put a react inside a loop using Actor.loop. As a result, you get loop { react { ... } } which, to me, seems pretty similar to while (true) { receive { ... } } which is used earlier in the book. Still, the book says that "in practice, programs will need at least a few receive's". So what am I missing here? What can receive do that react cannot, besides return? And why do I care? Finally, coming to the core of what I don't understand: the book keeps mentioning how using react makes it possible to discard the call stack to re-use the thread. How does that work? Why is it necessary to discard the call stack? And why can the call stack be discarded when a function terminates by throwing an exception (react), but not when it terminates by returning (receive)? I have the impression that Programming in Scala has been glossing over some of the key issues here, which is a shame, because otherwise it's a truly excellent book.

    Read the article

  • What's the best Scala build system?

    - by gatoatigrado
    I've seen questions about IDE's here -- Which is the best IDE for Scala development? and What is the current state of tooling for Scala?, but I've had mixed experiences with IDEs. Right now, I'm using the Eclipse IDE with the automatic workspace refresh option, and KDE 4's Kate as my text editor. Here are some of the problems I'd like to solve: use my own editor IDEs are really geared at everyone using their components. I like Kate better, but the refresh system is very annoying (it doesn't use inotify, rather, maybe a 10s polling interval). The reason I don't use the built-in text editor is because broken auto-complete functionalities cause the IDE to hang for maybe 10s. rebuild only modified files The Eclipse build system is broken. It doesn't know when to rebuild classes. I find myself almost half of the time going to project-clean. Worse, it seems even after it has finished building my project, a few minutes later it will pop up with some bizarre error (edit - these errors appear to be things that were previously solved with a project clean, but then come back up...). Finally, setting "Preferences / Continue launch if project contains errors" to "prompt" seems to have no effect for Scala projects (i.e. it always launches even if there are errors). build customization I can use the "nightly" release, but I'll want to modify and use my own Scala builds, not the compiler that's built into the IDE's plugin. It would also be nice to pass [e.g.] -Xprint:jvm to the compiler (to print out lowered code). fast compiling Though Eclipse doesn't always build right, it does seem snappy -- even more so than fsc. I looked at Ant and Maven, though haven't employed either yet (I'll also need to spend time solving #3 and #4). I wanted to see if anyone has other suggestions before I spend time getting a suboptimal build system working. Thanks in advance! UPDATE - I'm now using Maven, passing a project as a compiler plugin to it. It seems fast enough; I'm not sure what kind of jar caching Maven does. A current repository for Scala 2.8.0 is available [link]. The archetypes are very cool, and cross-platform support seems very good. However, about compile issues, I'm not sure if fsc is actually fixed, or my project is stable enough (e.g. class names aren't changing) -- running it manually doesn't bother me as much. If you'd like to see an example, feel free to browse the pom.xml files I'm using [github]. UPDATE 2 - from benchmarks I've seen, Daniel Spiewak is right that buildr's faster than Maven (and, if one is doing incremental changes, Maven's 10 second latency gets annoying), so if one can craft a compatible build file, then it's probably worth it...

    Read the article

  • Java WebStart: <property ...> ignored when using <extension>?

    - by Thorbjørn Ravn Andersen
    I have a problem modernizing a Java WebStart application under Java 6 u 13 (the latest at this moment) We desire to use the new mechanism to have several master configuration files each with their own configuration , which then "include" another jnlp file which is autogenerated to ensure that the jar list is accurate. After quite a bit of poking I have made it work, except for the fact that the properties defined in the master file is not available to the program when Main is invoked. The master JNLP looks like (anonymized): <jnlp> <information> <title>...</title> <vendor>...</vendor> <description>...</description> <description kind="short">...</description> <homepage href="http://....jnlp"/> <icon href="http://....gif"/> <!-- <offline-allowed/> --> </information> <security> <all-permissions/> </security> <resources> <j2se version="1.6+"/> <extension href="http://...extension.jnlp" /> <property name="server.name" value="SERVER"/> </resources> <application-desc main-class="Main"/> </jnlp> and the extension.jnlp looks like: <!-- Generated automatically. Do not edit! --> <jnlp> <information> <title>extension built 2009-04-22 12:39:58 CEST</title> <vendor>...</vendor> </information> <security><all-permissions/></security> <resources> <jar href="A.jar" /> <jar href="B.jar" /> <jar href="logback-classic-0.9.14.jar" /> <jar href="logback-core-0.9.14.jar" /> <jar href="slf4j-api-1.5.6.jar" /> </resources> <component-desc /> </jnlp> I have tried putting the proprty in the extension.jnlp too. Did not help. The JVM is reused and not relaunched according to the log in the Java Plugin Console. Any suggestions?

    Read the article

  • log4j performance

    - by Bob
    Hi, I'm developing a web app, and I'd like to log some information to help me improve and observe the app. (I'm using Tomcat6) First I thought I would use StringBuilders, append the logs to them and a task would persist them into the database like every 2 minutes. Because I was worried about the out-of-the-box logging system's performance. Then I made some test. Especially with log4j. Here is my code: Main.java public static void main(String[] args) { Thread[] threads = new Thread[LoggerThread.threadsNumber]; for(int i = 0; i < LoggerThread.threadsNumber; ++i){ threads[i] = new Thread(new LoggerThread("name - " + i)); } LoggerThread.startTimestamp = System.currentTimeMillis(); for(int i = 0; i < LoggerThread.threadsNumber; ++i){ threads[i].start(); } LoggerThread.java public class LoggerThread implements Runnable{ public static int threadsNumber = 10; public static long startTimestamp; private static int counter = 0; private String name; public LoggerThread(String name) { this.name = name; } private Logger log = Logger.getLogger(this.getClass()); @Override public void run() { for(int i=0; i<10000; ++i){ log.info(name + ": " + i); if(i == 9999){ int c = increaseCounter(); if(c == threadsNumber){ System.out.println("Elapsed time: " + (System.currentTimeMillis() - startTimestamp)); } } } } private synchronized int increaseCounter(){ return ++counter; } } } log4j.properties log4j.logger.main.LoggerThread=debug, f log4j.appender.f=org.apache.log4j.RollingFileAppender log4j.appender.f.layout=org.apache.log4j.PatternLayout log4j.appender.f.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n log4j.appender.f.File=c:/logs/logging.log log4j.appender.f.MaxFileSize=15000KB log4j.appender.f.MaxBackupIndex=50 I think this is a very common configuration for log4j. First I used log4j 1.2.14 then I realized there was a newer version, so I switched to 1.2.16 Here are the figures (all in millisec) LoggerThread.threadsNumber = 10 1.2.14: 4235, 4267, 4328, 4282 1.2.16: 2780, 2781, 2797, 2781 LoggerThread.threadsNumber = 100 1.2.14: 41312, 41014, 42251 1.2.16: 25606, 25729, 25922 I think this is very fast. Don't forget that: in every cycle the run method not just log into the file, it has to concatenate strings (name + ": " + i), and check an if test (i == 9999). When threadsNumber is 10, there are 100.000 loggings and if tests and concatenations. When it is 100, there are 1.000.000 loggings and if tests and concatenations. (I've read somewhere JVM uses StringBuilder's append for concatenation, not simple concatenation). Did I missed something? Am I doing something wrong? Did I forget any factor that could decrease the performance? If these figures are correct I think, I don't have to worry about log4j's performance even if I heavily log, do I?

    Read the article

  • Zero code coverage with cobertura 1.9.2 but tests are working

    - by eraonel
    I run the code coverage target: <junit fork="yes" dir="${basedir}" failureProperty="test.failed"> <!-- Note the classpath order: instrumented classes are before the original (uninstrumented) classes. This is important. --> <classpath path="${instrumented.dir}" /> <classpath path="${classes.dir}" /> <classpath refid="classpath" /> <!-- The instrumented classes reference classes used by the Cobertura runtime, so Cobertura and its dependencies must be on your classpath. --> <classpath refid="cobertura.classpath" /> <formatter type="xml" /> <!--<test name="${testcase}" todir="${reports.xml.dir}" if="testcase" />--> <batchtest fork="yes" todir="${reports.xml.dir}"> <fileset dir="${classes.dir}"> <include name="**/generated/AllTests.class" /> </fileset> </batchtest> </junit> <junitreport todir="${reports.xml.dir}"> <fileset dir="${reports.xml.dir}"> <include name="TEST-*.xml" /> </fileset> <report format="frames" todir="${reports.html.dir}" /> </junitreport> Then I get the following output ( when using fork="true"): java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at net.sourceforge.cobertura.util.FileLocker.lock(FileLocker.java:124) at net.sourceforge.cobertura.coveragedata.ProjectData.saveGlobalProjectData(ProjectData.java:331) at net.sourceforge.cobertura.coveragedata.SaveTimer.run(SaveTimer.java:31) at java.lang.Thread.run(Thread.java:595) Caused by: java.io.IOException: No locks available at sun.nio.ch.FileChannelImpl.lock0(Native Method) at sun.nio.ch.FileChannelImpl.lock(FileChannelImpl.java:784) at java.nio.channels.FileChannel.lock(FileChannel.java:865) ... 8 more --------------------------------------- Unable to get lock on /vobs/rnc/rrt/roam2/roamSs/RoamMao_swb/RoamMao_bldu/ant_build/cobertura.ser.lock: null This is known to happen on Linux kernel 2.6.20. Make sure cobertura.jar is in the root classpath of the jvm process running the instrumented code. If the instrumented code is running in a web server, this means cobertura.jar should be in the web server's lib directory. Don't put multiple copies of cobertura.jar in different WEB-INF/lib directories. Only one classloader should load cobertura. It should be the root classloader. I am using Ant 1.7.0 and cobertura 1.9.2. Any ideas why there is no coverage? Test run ok as I see in my target. I have tried to switch java versions ( 1.5.0_06 and 1.6.0_10) but no difference.

    Read the article

  • What does these FindBug messages show?

    - by Hans Klock
    Not every description from from http://findbugs.sourceforge.net/bugDescriptions.html is clear to me. Sure, I can study the implementation but if somebody is more experienced then me, some explanation and examples would be great. Do you have some examples for UI_INHERITANCE_UNSAFE_GETRESOURCE when this is getting a problem? In BX_UNBOXED_AND_COERCED_FOR_TERNARY_OPERATOR I don't see the problem either. If one type is "bigger" then the other, for example int and float, then the result is float. If its Integer and Float its the wrapper Float too. That's what I expect. Does the GC_UNRELATED_TYPES really help to find errors? Isn't it the job of the compiler to check, if--taking the given example--Foo can't go into a Collection<String>. Does HE_SIGNATURE_DECLARES_HASHING_OF_UNHASHABLE_CLASS mean something like bla(Foo f){hashtable.put(f);}, where ´Foo´ is not hashable? Does FingBugs "see" the subclasses too? NP_GUARANTEED_DEREF_ON_EXCEPTION_PATH is stronger "wrong" then NP_ALWAYS_NULL_EXCEPTION? Why two error cases and with NP_NULL_ON_SOME_PATH_EXCEPTION even one more? Sounds very similar to me. What is an example of SIO_SUPERFLUOUS_INSTANCEOF? Something like foo(String s){if (s intenceof String) .... This does a null check too, but this is not the test here... NN_NAKED_NOTIFY. I my opinion the description is not clear. A change of the state is not necessary. If I use new Object() to wait and notify on I don't change the object state. Or is state the lock-state? I don't get it. SP_SPIN_ON_FIELD. Can this really happen that a compiler will move this outside from a loop? This doesn't make sense to me because from outside a Thread can always change the values. And if the variable is volatile the JVM can't cache the value. So what's the meaning? That is the difference between STCAL_STATIC_CALENDAR_INSTANCE and STCAL_INVOKE_ON_STATIC_CALENDAR_INSTANCE or STCAL_INVOKE_ON_STATIC_DATE_FORMAT_INSTANCE/STCAL_STATIC_SIMPLE_DATE_FORMAT_INSTANCE? Why is XXXX.class in WL_USING_GETCLASS_RATHER_THAN_CLASS_LITERAL better then getClass()? A getClass() in a superclass called from the subclass will always return the Class object from the subclass which is good I think. What exactly does EQ_UNUSUAL do? It should check that the argument is of the same type of the class itself but it does't? Did you ever had problems with breaks? Is there real value with SF_SWITCH_FALLTHROUGH? Sounds to strong for me. No idea what TQ_EXPLICIT_UNKNOWN_SOURCE_VALUE_REACHES_ALWAYS_SINK and TQ_EXPLICIT_UNKNOWN_SOURCE_VALUE_REACHES_NEVER_SINK could be.

    Read the article

  • Difference in DocumentBuilder.parse when using JRE 1.5 and JDK 1.6

    - by dhiller
    Recently at last we have switched our projects to Java 1.6. When executing the tests I found out that using 1.6 a SAXParseException is not thrown which has been thrown using 1.5. Below is my test code to demonstrate the problem. import java.io.StringReader; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.transform.stream.StreamSource; import javax.xml.validation.SchemaFactory; import org.junit.Test; import org.xml.sax.InputSource; import org.xml.sax.SAXParseException; /** * Test class to demonstrate the difference between JDK 1.5 to JDK 1.6. * * Seen on Linux: * * <pre> * #java version "1.6.0_18" * Java(TM) SE Runtime Environment (build 1.6.0_18-b07) * Java HotSpot(TM) Server VM (build 16.0-b13, mixed mode) * </pre> * * Seen on OSX: * * <pre> * java version "1.6.0_17" * Java(TM) SE Runtime Environment (build 1.6.0_17-b04-248-10M3025) * Java HotSpot(TM) 64-Bit Server VM (build 14.3-b01-101, mixed mode) * </pre> * * @author dhiller (creator) * @author $Author$ (last editor) * @version $Revision$ * @since 12.03.2010 11:32:31 */ public class TestXMLValidation { /** * Tests the schema validation of an XML against a simple schema. * * @throws Exception * Falls ein Fehler auftritt * @throws junit.framework.AssertionFailedError * Falls eine Unit-Test-Pruefung fehlschlaegt */ @Test(expected = SAXParseException.class) public void testValidate() throws Exception { final StreamSource schema = new StreamSource( new StringReader( "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" + "<xs:schema xmlns:xs=\"http://www.w3.org/2001/XMLSchema\" " + "elementFormDefault=\"qualified\" xmlns:xsd=\"undefined\">" + "<xs:element name=\"Test\"/>" + "</xs:schema>" ) ); final String xml = "<Test42/>"; final DocumentBuilderFactory newFactory = DocumentBuilderFactory.newInstance(); newFactory.setSchema( SchemaFactory.newInstance( "http://www.w3.org/2001/XMLSchema" ).newSchema( schema ) ); final DocumentBuilder documentBuilder = newFactory.newDocumentBuilder(); documentBuilder.parse( new InputSource( new StringReader( xml ) ) ); } } When using a JVM 1.5 the test passes, on 1.6 it fails with "Expected exception SAXParseException". The Javadoc of the DocumentBuilderFactory.setSchema(Schema) Method says: When errors are found by the validator, the parser is responsible to report them to the user-specified ErrorHandler (or if the error handler is not set, ignore them or throw them), just like any other errors found by the parser itself. In other words, if the user-specified ErrorHandler is set, it must receive those errors, and if not, they must be treated according to the implementation specific default error handling rules. The Javadoc of the DocumentBuilder.parse(InputSource) method says: BTW: I tried setting an error handler via setErrorHandler, but there still is no exception. Now my question: What has changed to 1.6 that prevents the schema validation to throw a SAXParseException? Is it related to the schema or to the xml that I tried to parse?

    Read the article

  • Java Runtime.freeMemory() returning bizarre results when adding more objects

    - by Sotirios Delimanolis
    For whatever reason, I wanted to see how many objects I could create and populate a LinkedList with. I used Runtime.getRuntime().freeMemory() to get the approximation of free memory in my JVM. I wrote this: public static void main(String[] arg) { Scanner kb = new Scanner(System.in); List<Long> mem = new LinkedList<Long>(); while (true) { System.out.println("Max memory: " + Runtime.getRuntime().maxMemory() + ". Available memory: " + Runtime.getRuntime().freeMemory() + " bytes. Press enter to use more."); String s = kb.nextLine(); if (s.equals("m")) for (int i = 0; i < 1000000; i++) { mem.add(new Long((new Random()).nextLong())); } } } If I write in m, the app adds a million Long objects to the list. You would think the more objects (to which we have references, so can't be gc'ed), the less free memory. Running the code: Max memory: 1897725952. Available memory: 127257696 bytes. m Max memory: 1897725952. Available memory: 108426520 bytes. m Max memory: 1897725952. Available memory: 139873296 bytes. m Max memory: 1897725952. Available memory: 210632232 bytes. m Max memory: 1897725952. Available memory: 137268792 bytes. m Max memory: 1897725952. Available memory: 239504784 bytes. m Max memory: 1897725952. Available memory: 169507792 bytes. m Max memory: 1897725952. Available memory: 259686128 bytes. m Max memory: 1897725952. Available memory: 189293488 bytes. m Max memory: 1897725952. Available memory: 387686544 bytes. The available memory fluctuates. How does this happen? Is the GC cleaning up other things (what other things are there on the heap to really clean up?), is the freeMemory() method returning an approximation that's way off? Am I missing something or am I crazy?

    Read the article

  • Memory Leak with Swing Drag and Drop

    - by tom
    I have a JFrame that accepts top-level drops of files. However after a drop has occurred, references to the frame are held indefinitely inside some Swing internal classes. I believe that disposing of the frame should release all of its resources, so what am I doing wrong? Example import java.awt.datatransfer.DataFlavor; import java.io.File; import java.util.List; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.TransferHandler; public class DnDLeakTester extends JFrame { public static void main(String[] args) { new DnDLeakTester(); //Prevent main from returning or the jvm will exit while (true) { try { Thread.sleep(10000); } catch (InterruptedException e) { } } } public DnDLeakTester() { super("I'm leaky"); add(new JLabel("Drop stuff here")); setTransferHandler(new TransferHandler() { @Override public boolean canImport(final TransferSupport support) { return (support.isDrop() && support .isDataFlavorSupported(DataFlavor.javaFileListFlavor)); } @Override public boolean importData(final TransferSupport support) { if (!canImport(support)) { return false; } try { final List<File> files = (List<File>) support.getTransferable().getTransferData(DataFlavor.javaFileListFlavor); for (final File f : files) { System.out.println(f.getName()); } } catch (Exception e) { e.printStackTrace(); } return true; } }); setDefaultCloseOperation(DISPOSE_ON_CLOSE); pack(); setVisible(true); } } To reproduce, run the code and drop some files on the frame. Close the frame so it's disposed of. To verify the leak I take a heap dump using JConsole and analyse it with the Eclipse Memory Analysis tool. It shows that sun.awt.AppContext is holding a reference to the frame through its hashmap. It looks like TransferSupport is at fault. What am I doing wrong? Should I be asking the DnD support code to clean itself up somehow? I'm running JDK 1.6 update 19.

    Read the article

  • Why does every thread in my application use a different hibernate session?

    - by Ittai
    Hi, I have a web-application which uses hibernate and for some reason every thread (httprequest or other threads related to queueing) uses a different session. I've implemented a HibernateSessionFactory class which looks like this: public class HibernateSessionFactory { private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>(); private static Configuration configuration = new AnnotationConfiguration(); private static org.hibernate.SessionFactory sessionFactory; static { try { configuration.configure(configFile); sessionFactory = configuration.buildSessionFactory(); } catch (Exception e) {} } private HibernateSessionFactory() {} public static Session getSession() throws HibernateException { Session session = (Session) threadLocal.get(); if (session == null || !session.isOpen()) { if (sessionFactory == null) { rebuildSessionFactory();//This method basically does what the static init block does } session = (sessionFactory != null) ? sessionFactory.openSession(): null; threadLocal.set(session); } return session; } //More non relevant methods here. Now from my testing it seems that the threadLocal member is indeed initialized only once when the class is first loaded by the JVM but for some reason when different threads access the getSession() method they use different sessions. When a thread first accesses this class (Session) threadLocal.get(); will return null but as expected all other access requests will yeild the same session. I'm not sure how this can be happening as the threadLocal variable is final and the method threadLocal.set(session) is only used in the above context (which I'm 99.9% sure has to yeild a non null session as I would have encountered a NullPointerException at a different part of my app). I'm not sure this is relevant but these are the main parts of my hibernate.cfg.xml file: <hibernate-configuration> <session-factory> <property name="connection.url">someURL</property> <property name="connection.driver_class"> com.microsoft.sqlserver.jdbc.SQLServerDriver</property> <property name="dialect">org.hibernate.dialect.SQLServerDialect</property> <property name="hibernate.connection.isolation">1</property> <property name="hibernate.connection.username">User</property> <property name="hibernate.connection.password">Password</property> <property name="hibernate.connection.pool_size">10</property> <property name="show_sql">false</property> <property name="current_session_context_class">thread</property> <property name="hibernate.hbm2ddl.auto">update</property> <property name="hibernate.cache.use_second_level_cache">false</property> <property name="hibernate.cache.provider_class">org.hibernate.cache.NoCacheProvider</property> <!-- Mapping files --> I'd appreciate any help granted and of course if anyone has any questions I'd be happy to clarify. Ittai

    Read the article

  • Techniques for querying a set of object in-memory in a Java application

    - by Edd Grant
    Hi All, We have a system which performs a 'coarse search' by invoking an interface on another system which returns a set of Java objects. Once we have received the search results I need to be able to further filter the resulting Java objects based on certain criteria describing the state of the attributes (e.g. from the initial objects return all objects where x.y z && a.b == c). The criteria used to filter the set of objects each time is partially user configurable, by this I mean that users will be able to select the values and ranges to match on but the attributes they can pick from will be a fixed set. The data sets are likely to contain <= 10,000 objects for each search. The search will be executed manually by the application user base probably no more than 2000 times a day (approx). It's probably worth mentioning that all the objects in the result set are known domain object classes which have Hibernate and JPA annotations describing their structure and relationship. Off the top of my head I can think of 3 ways of doing this: For each search persist the initial result set objects in our database, then use Hibernate to re-query them using the finer grained criteria. Use an in-memory Database (such as hsqldb?) to query and refine the initial result set. Write some custom code which iterates the initial result set and pulls out the desired records. Option 1 seems to involve a lot of toing and froing across a network to a physical Database (Oracle 10g) which might result in a lot of network and disk activity. It would also require the results from each search to be isolated from other result sets to ensure that different searches don't interfere with each other. Option 2 seems like a good idea in principle as it would allow me to do the finer query in memory and would not require the persistence of result data which would only be discarded after the search was complete. Gut feeling is that this could be pretty performant too but might result in larger memory overheads (which is fine as we can be pretty flexible on the amount of memory our JVM gets). Option 3 could be very performant but is something I would like to avoid as any code we write would require such careful testing that the time taken to acheive something flexible and robust enough would probably be prohibitive. I don't have time to prototype all 3 ideas so I am looking for comments people may have on the 3 options above, plus any further ideas I have not considered, to help me decide which idea might be most suitable. I'm currently leaning toward option 2 (in memory database) so would be keen to hear from people with experience of querying POJOs in memory too. Hopefully I have described the situation in enough detail but don't hesitate to ask if any further information is required to better understand the scenario. Cheers, Edd

    Read the article

  • Interview questions about ASP.NET Web services.

    - by Jalpesh P. Vadgama
    I have seen there are lots of myth’s about asp.net web services in fresher level asp.net developers. So I decided to write a blog post about asp.net web services interview questions. Because I think this is the best way to reach fresher asp.net developers. Followings are few questions about asp.net web services. 1) What is asp.net web services? Ans: Web services are used to support http requests that formatted using xml,http and SOAP syntax. They interact with through standards xml messages through Soap. They are used to support interoperability. It has .asmx extension and .NET framework contains http handlers for web services to support http requested directly. 2) What kind of data can be returned web services web methods? Ans: It supports all the primitive data types and custom data types that can be encoded and serialized by xml. You can find more information about that from the following link. http://msdn.microsoft.com/en-us/library/bb552900.aspx 3) Is web services are only written in asp.net? Ans: No, It can be written by Java and PHP languages also. 4) Explain web method attributes in web services Ans: Web method attributes are added to a public class method to indicate that this method is exposed as a part of XML web services. You can have multiple web methods in a class. But it should be having public attributes as it will be exposed as xml web service part. You can find more information about web method attributes from following link. http://msdn.microsoft.com/en-us/library/byxd99hx(v=vs.71).aspx 5) What is SOA? Ans: SOA stands for “Services Oriented Architecture”. It is kind of service oriented architecture used to support different kind of computing platforms and applications. Web services in asp.net are one of the technologies that supports that kind of architecture.  You can call asp.net web services from any computing platforms and applications. 6) What is SOAP,WDSL and UDDI? Ans: SOAP stands “Simple Object Access protocol”. Web services will be interact with SOAP messages written in XML. SOAP is sometimes referred as “data wrapper” or “data envelope”.Its contains different xml tag that creates a whole SOAP message.  WSDL stand for “Web services Description Language”.  It is an xml document which is written according to standard specified by W3c. It is a kind of manual or document that describes how we can use and consume web service. Web services development software processes the WSDL document and generates SOAP messages that are needed for specific web service. UDDI stand for “Universal Discovery, Description and Integration”. Its is used for web services registries. You can find addresses of web services from UDDI.

    Read the article

  • C# Proposal: Compile Time Static Checking Of Dynamic Objects

    - by Paulo Morgado
    C# 4.0 introduces a new type: dynamic. dynamic is a static type that bypasses static type checking. This new type comes in very handy to work with: The new languages from the dynamic language runtime. HTML Document Object Model (DOM). COM objects. Duck typing … Because static type checking is bypassed, this: dynamic dynamicValue = GetValue(); dynamicValue.Method(); is equivalent to this: object objectValue = GetValue(); objectValue .GetType() .InvokeMember( "Method", BindingFlags.InvokeMethod, null, objectValue, null); Apart from caching the call site behind the scenes and some dynamic resolution, dynamic only looks better. Any typing error will only be caught at run time. In fact, if I’m writing the code, I know the contract of what I’m calling. Wouldn’t it be nice to have the compiler do some static type checking on the interactions with these dynamic objects? Imagine that the dynamic object that I’m retrieving from the GetValue method, besides the parameterless method Method also has a string read-only Property property. This means that, from the point of view of the code I’m writing, the contract that the dynamic object returned by GetValue implements is: string Property { get; } void Method(); Since it’s a well defined contract, I could write an interface to represent it: interface IValue { string Property { get; } void Method(); } If dynamic allowed to specify the contract in the form of dynamic(contract), I could write this: dynamic(IValue) dynamicValue = GetValue(); dynamicValue.Method(); This doesn’t mean that the value returned by GetValue has to implement the IValue interface. It just enables the compiler to verify that dynamicValue.Method() is a valid use of dynamicValue and dynamicValue.OtherMethod() isn’t. If the IValue interface already existed for any other reason, this would be fine. But having a type added to an assembly just for compile time usage doesn’t seem right. So, dynamic could be another type construct. Something like this: dynamic DValue { string Property { get; } void Method(); } The code could now be written like this; DValue dynamicValue = GetValue(); dynamicValue.Method(); The compiler would never generate any IL or metadata for this new type construct. It would only thee used for compile type static checking of dynamic objects. As a consequence, it makes no sense to have public accessibility, so it would not be allowed. Once again, if the IValue interface (or any other type definition) already exists, it can be used in the dynamic type definition: dynamic DValue : IValue, IEnumerable, SomeClass { string Property { get; } void Method(); } Another added benefit would be IntelliSense. I’ve been getting mixed reactions to this proposal. What do you think? Would this be useful?

    Read the article

  • GPGPU

    WhatGPU obviously stands for Graphics Processing Unit (the silicon powering the display you are using to read this blog post). The extra GP in front of that stands for General Purpose computing.So, altogether GPGPU refers to computing we can perform on GPU for purposes beyond just drawing on the screen. In effect, we can use a GPGPU a bit like we already use a CPU: to perform some calculation (that doesn’t have to have any visual element to it). The attraction is that a GPGPU can be orders of magnitude faster than a CPU.WhyWhen I was at the SuperComputing conference in Portland last November, GPGPUs were all the rage. A quick online search reveals many articles introducing the GPGPU topic. I'll just share 3 here: pcper (ignoring all pages except the first, it is a good consumer perspective), gizmodo (nice take using mostly layman terms) and vizworld (answering the question on "what's the big deal").The GPGPU programming paradigm (from a high level) is simple: in your CPU program you define functions (aka kernels) that take some input, can perform the costly operation and return the output. The kernels are the things that execute on the GPGPU leveraging its power (and hence execute faster than what they could on the CPU) while the host CPU program waits for the results or asynchronously performs other tasks.However, GPGPUs have different characteristics to CPUs which means they are suitable only for certain classes of problem (i.e. data parallel algorithms) and not for others (e.g. algorithms with branching or recursion or other complex flow control). You also pay a high cost for transferring the input data from the CPU to the GPU (and vice versa the results back to the CPU), so the computation itself has to be long enough to justify the overhead transfer costs. If your problem space fits the criteria then you probably want to check out this technology.HowSo where can you get a graphics card to start playing with all this? At the time of writing, the two main vendors ATI (owned by AMD) and NVIDIA are the obvious players in this industry. You can read about GPGPU on this AMD page and also on this NVIDIA page. NVIDIA's website also has a free chapter on the topic from the "GPU Gems" book: A Toolkit for Computation on GPUs.If you followed the links above, then you've already come across some of the choices of programming models that are available today. Essentially, AMD is offering their ATI Stream technology accessible via a language they call Brook+; NVIDIA offers their CUDA platform which is accessible from CUDA C. Choosing either of those locks you into the GPU vendor and hence your code cannot run on systems with cards from the other vendor (e.g. imagine if your CPU code would run on Intel chips but not AMD chips). Having said that, both vendors plan to support a new emerging standard called OpenCL, which theoretically means your kernels can execute on any GPU that supports it. To learn more about all of these there is a website: gpgpu.org. The caveat about that site is that (currently) it completely ignores the Microsoft approach, which I touch on next.On Windows, there is already a cross-GPU-vendor way of programming GPUs and that is the DirectX API. Specifically, on Windows Vista and Windows 7, the DirectX 11 API offers a dedicated subset of the API for GPGPU programming: DirectCompute. You use this API on the CPU side, to set up and execute the kernels that run on the GPU. The kernels are written in a language called HLSL (High Level Shader Language). You can use DirectCompute with HLSL to write a "compute shader", which is the term DirectX uses for what I've been referring to in this post as a "kernel". For a comprehensive collection of links about this (including tutorials, videos and samples) please see my blog post: DirectCompute.Note that there are many efforts to build even higher level languages on top of DirectX that aim to expose GPGPU programming to a wider audience by making it as easy as today's mainstream programming models. I'll mention here just two of those efforts: Accelerator from MSR and Brahma by Ananth. Comments about this post welcome at the original blog.

    Read the article

  • Keeping up with Technology

    - by kennedysteve
    If you're like me, you have a hard time keeping up with all the technologies out there. The reality is there's too many new technologies (languages, methodologies,  tools, etc). One of the ways I try to keep up with everything is by using good ol' RSS feeds in conjunction with Google Reader. Google Reader is both an online aggregator of RSS feeds, and it also has a good companion app on Google Android. The nicest part of Google Reader for me is the "All Listings" view which gives me a reverse chronological view of ALL articles (mixed together) regardless of the actual RSS feed.  This way, I get to see the newest articles first. I can then choose to hide the articles I've viewed, etc. Here is a list of my RSS feeds. Admittedly, some of these are all over the spectrum. But you might find one or two interesting. .NET Rocks! RSS = http://feeds.feedburner.com/netRocksFullMp3Downloads Main Web Site = http://www.dotnetrocks.com Channel 9 RSS = http://channel9.msdn.com/Feeds/RSS Main Web Site = http://channel9.msdn.com/ CodePlex  RSS = http://www.codeplex.com/site/feeds/rss Main Web Site = http://www.codeplex.com/site/feeds/rss Connected Show Developer Podcast! RSS = http://feeds.connectedshow.com/ConnectedShow Main Web Site = http://www.ConnectedShow.com/ dnrTV RSS = http://feeds.feedburner.com/DnrtvWmv?format=xml Main Web Site = http://dnrtv.com ebookshare RSS = http://www.ebookshare.net/feed/ Main Web Site = http://www.ebookshare.net Geekswithblogs.net RSS = http://feeds.feedburner.com/geekswithblogs Main Web Site = http://geekswithblogs.net/mainfeed.aspx Gmail Blog RSS = http://feeds.feedburner.com/OfficialGmailBlog?format=xml Main Web Site = http://gmailblog.blogspot.com/ Google Mobile Blog RSS = http://feeds.feedburner.com/OfficialGoogleMobileBlog Main Web Site = http://googlemobile.blogspot.com/ Herding Code RSS = http://feeds.feedburner.com/herdingcode Main Web Site = http://herdingcode.com LearnVisualStudio.NET Videos RSS = http://www.learnvisualstudio.net/videos.rss Main Web Site = http://www.learnvisualstudio.net/ Microsoft Learning Upcoming = Microsoft Learning Upcoming Titles RSS = http://learning.microsoft.com/rss/en-US/upcomingtitles?brand=Learning Main Web Site = http://learning.microsoft.com:80/rss/en-US/upcomingtitles?brand=Learning MS On-demand Webcasts RSS = http://www.microsoft.com/communities/rss.aspx?&Title=On-Demand+Webcasts&RssTitle=Microsoft+Webcasts%3A+On-Demand+Webcasts&CMTYSvcSource=MSCOMMedia&WebNewsURL=http%3A%2F%2Fwww.microsoft.com%2Fevents%2FEventDetails.aspx&CMTYRawShape=list&Params=+%0D%0A%09~CMTYDataSvcParams%5E%0D%0A%09~arg+Name%3D'EventType'+Value%3D'OnDemandWebcast'%2F%5E%0D%0A%09~arg+Name%3D'ProviderID'+Value%3D'A6B43178-497C-4225-BA42-DF595171F04C'%2F%5E%0D%0A%09~arg+Name%3D'StartDate'+Value%3D'06%2F30%2F2006'%2F%5E%0D%0A%09~arg+Name%3D'EndDate'+Value%3D'Now%2B0'%2F%5E%0D%0A%09~%2FCMTYDataSvcParams%5E+&NumberOfItems=100 Main Web Site = http://www.microsoft.com/events/default.mspx MS Podcasts for Devs RSS = http://www.microsoft.com/events/podcasts/default.aspx?podcast=rss&audience=Audience-e5381407-359f-4922-97d0-0237af790eee&pageId=x40 Main Web Site = http://www.microsoft.com/events/podcasts/default.aspx?audience=Audience-e5381407-359f-4922-97d0-0237af790eee&pageId=x40&WT.rss_ev=f MSDN Blogs RSS = http://blogs.msdn.com/b/mainfeed.aspx?Type=BlogsOnly Main Web Site = http://blogs.msdn.com/b/ MSDN Radio RSS = http://www.microsoft.com/events/podcasts/default.aspx?topic=&audience=&view=&pageId=x73&seriesID=Series-b9139976-8d48-4249-9b89-ccd17891de1e.xml&podcast=rss&type=wma Main Web Site = http://www.microsoft.com/events/podcasts/default.aspx?seriesID=Series-b9139976-8d48-4249-9b89-ccd17891de1e.xml&pageId=x73&WT.rss_ev=f O'Reilly Deal of the Day RSS = http://feeds.feedburner.com/oreilly/ebookdealoftheday Main Web Site = http://oreilly.com O'Reilly New RSS = http://feeds.feedburner.com/oreilly/newbooks Main Web Site = http://oreilly.com/ Safari Books Online RSS = http://my.safaribooksonline.com/rss Main Web Site = http://my.safaribooksonline.com/ ScottGu's Blog RSS = http://weblogs.asp.net/scottgu/rss.aspx Main Web Site = http://weblogs.asp.net/scottgu/default.aspx SourceForge Community Blog RSS = http://sourceforge.net/blog/feed/ Main Web Site = http://sourceforge.net/blog Stack Overflow RSS = http://blog.stackoverflow.com/feed/ Main Web Site = http://blog.stackoverflow.com Stepcase Lifehack RSS = http://www.lifehack.org/feed/ Main Web Site = http://www.lifehack.org TechNet Radio RSS = http://www.microsoft.com/events/podcasts/default.aspx?topic=&audience=&view=&pageId=x73&seriesID=Series-cc4e3db2-9212-43c5-a57b-d43fa31e6452.xml&podcast=rss&type=wma Main Web Site = http://www.microsoft.com/events/podcasts/default.aspx?seriesID=Series-cc4e3db2-9212-43c5-a57b-d43fa31e6452.xml&pageId=x73&WT.rss_ev=f Wrox All New Titles RSS = http://www.wrox.com/WileyCDA/feed/RSS_WROX_ALLNEW.xml Main Web Site = http://www.wrox.com

    Read the article

  • Windows CE Chat Transcript (March 30, 2010)

    - by Bruce Eitman
    For those of you who missed the chat today, here is the raw transcript.   By raw, I mean that I copied and pasted the discussion without any edits. This is divided into two parts, the top part is the answers from the Microsoft Experts and the bottom part is the questions from the audience. Answers from Microsoft:   Karel Danihelka [MS] (Expert)[2010-3-30 12:2]: Hi everyone, my name is Karel Danihelka and I am developer in partner response team. Sing Wee [MS] (Expert)[2010-3-30 12:2]: Hi, I'm Sing Wee, part of the CoreOS/BSP Test Team. GLanger_MS (Expert)[2010-3-30 12:2]: Hi, I'm Glen Langer, program manager on the Core Team. Karel Danihelka [MS] (Expert)[2010-3-30 12:3]: Q: I need to implement hardware timers on my windows CE 6.0 device to trigger events at microsecond intervals. Where should i start? A: Until you are using CPU with GHz frequency your only chance is use interrupt handler and implement all funcionality there. But it will be really tricky and may reduce system performance. If period will be near to millisecond timeframe you can use normal thread wait for event pattern. Karel Danihelka [MS] (Expert)[2010-3-30 12:5]: Q: I want to partition my NAND Flash device. One partition to use for hive ragistry and the other for the apps and data. The only way to do it is programmatically or setting some registry values ? A: It need to be set in registry - generally you need mark this partition as boot partition. Karel Danihelka [MS] (Expert)[2010-3-30 12:7]: Q: My CPU is Intel celeron M processor 1Ghz. A: In this case you can try use normal approach - in interrupt handler return SYSINTR and start thread in device driver which will spin thread waiting on event attached to this SYSINTR. Karel Danihelka [MS] (Expert)[2010-3-30 12:7]: Q: If i need to implement it using interrupt handlers, What are all the files that I should look at? A: Good quesiton - I would recommend documentation and there was BSP development book to download for free. mikehall_ms (Moderator)[2010-3-30 12:8]: Q: Hi guys, what's the formal way to report bugs back to the core team / product team? The mechanism of calling the support phone number every time is really onerous and time-consuming. Is there another mechanism? A: Using product support is the formal way to report bugs/issues - Product support can then create an issue that can be tracked. Karel Danihelka [MS] (Expert)[2010-3-30 12:9]: Q: But the operation for creating the partitions ? A: This is tricky - if you will make it autopartition & autoformat it will be created by filesystem. But generally it depends on your boot loader. mikehall_ms (Moderator)[2010-3-30 12:10]: Q: Is Windows Phone 7 related to Windows CE? If so, can you tell me what version of Windows CE is the basis? Is it in fact the new version of Windows Mobile? A: At MIX 2010 Charlie Kindel presented a session that described some of the core technologies that make up Windows Phone 7 Series, including the underlying operating system (Windows CE) and the new ISV programming model based on Silverlight and .NET - check out the Mix Online Videos to get more information. davbo-msft (Moderator)[2010-3-30 12:10]: Q: Is Windows Phone 7 related to Windows CE? If so, can you tell me what version of Windows CE is the basis? Is it in fact the new version of Windows Mobile? A: This forum is to discussed released products in the industry. Windows Mobile & Windows CE are based on the same Windows CE Kernel/system. Windows CE is focused on deliverying the OS for embedded customers in the market where Windows Mobile is focused on deliverying compelling Windows Phone platform. davbo-msft (Moderator)[2010-3-30 12:11]: Q: Is Windows Phone 7 related to Windows CE? If so, can you tell me what version of Windows CE is the basis? Is it in fact the new version of Windows Mobile? A: http://en.wikipedia.org/wiki/Windows_CE Wikipedia gives a good breakdown of the version history. Travis Hobrla [MS] (Expert)[2010-3-30 12:13]: Q: I created a OS design with KITL and kernel debugger enabled. But I am unable to connect to the target for debugging. I am getting the following error when i try to connect with the device. PB Debugger Cannot initialize the Kernel Debugger. PB Debugger Debugger could not initialize connection. PB Debugger The Kernel Debugger is waiting to connect with target. PB Debugger The Kernel Debugger has been disconnected successfully. A: One possibility is that a rogue cesvchost.exe has co-opted the debugger. I am assuming this is CE 6.0? Can you try exiting visual studio and manually killing the cesvchost.exe process from the Task Manager? davbo-msft (Moderator)[2010-3-30 12:14]: Q: Hi guys, what's the formal way to report bugs back to the core team / product team? The mechanism of calling the support phone number every time is really onerous and time-consuming. Is there another mechanism? A: For info on contacting Microsoft support refer to the support page on the Embedded website: http://msdn.microsoft.com/en-us/windowsembedded/dd897633.aspx Sing Wee [MS] (Expert)[2010-3-30 12:16]: Q: Do u mean ISR/IST implementation? How can i register an interrupt? What kind of interrupt should i register? A: A good introduction to interrupts in WinCE 6.0 can be found here (aside from the documentation on MSDN): http://download.microsoft.com/download/9/c/f/9cffaa58-4000-48d6-a4b2-5fed9e4e6410/Chapter%206%20-%20Developing%20Device%20Drivers.pdf mikehall_ms (Moderator)[2010-3-30 12:16]: Q: What will be different in Windows Compact 7 from CE 6.0? A: Unfortunately we cannot discuss unreleased products on this chat - keep an eye on the Windows Embedded web site and blogs to keep up to date with product announcements. Travis Hobrla [MS] (Expert)[2010-3-30 12:16]: Q: I am using CE 6.0. There is no cesvchost process running in my system. A: What operating system are you using? Karel Danihelka [MS] (Expert)[2010-3-30 12:16]: Q: So...I have to modify file system code to create 2 partition at system startup ?!! I haven't understood.... A: You don't need to modify code, there are registry settings to achive this (look to documentation). But you may need to create partition table in boot loader. Unfortunatelly there isn't simple way how to do it. davbo-msft (Moderator)[2010-3-30 12:18]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? A: Windows Embedded CE 6.0 R3 includes Sliverlight for Windows Embedded. Refer to New Features overview on the embedded web site. http://www.microsoft.com/windowsembedded/en-us/products/windowsce/default.mspx. Silverlight - The power of Silverlight brought to Windows Embedded CE to create rich applications and user interfaces is new part of Windows CE Embedded. mikehall_ms (Moderator)[2010-3-30 12:20]: Q: The link for developing device drivers is not working. can u please check that? A: http://msdn.microsoft.com/en-us/library/ms923714.aspx davbo-msft (Moderator)[2010-3-30 12:20]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? A: Sorry misunderstood the question I thought you were asking if embedded CE could handle Silverlight. Please repost so that the question goes back into the active queue because once answered no way to put the status back to open. Travis Hobrla [MS] (Expert)[2010-3-30 12:21]: Q: sorry! Windows XP SP3 A: Can you try exiting VS2005 and confirming cesvchost.exe is not running, then renaming C:\Documents and Settings\USERNAME\Local Settings\Application Data\Microsoft\CoreCon\1.0 to 1.0_backup, then restarting VS2005? Sing Wee [MS] (Expert)[2010-3-30 12:24]: Q: Can I have the book's name please? A: I believe the downloadable version is related to the last link I sent. If you go to the following website, I believe you can download the whole thing: http://msdn.microsoft.com/en-us/windowsembedded/ce/cc294468.aspx davbo-msft (Moderator)[2010-3-30 12:24]: Q: If one has an image on a Silverlight page, it seems to be cached. How would one refresh that cache after changing the underlying image? A: change the URI of the image or use a writeable bitmap if they want to manually toggle the pixels Sing Wee [MS] (Expert)[2010-3-30 12:25]: A: Whoops, hit [ENTER] too early. On the right side, you'll see there an "Exam Preparation Kit" link that can be downloaded in several different languages. Sing Wee [MS] (Expert)[2010-3-30 12:25]: Q: Can I have the book's name please? A: Whoops, hit [ENTER] too early. On the right side, you'll see there an "Exam Preparation Kit" link that can be downloaded in several different languages. Karel Danihelka [MS] (Expert)[2010-3-30 12:26]: Q: I have a NAND Flash on my target device. On this flash I have the hive registry and an application.I have observed that when the NAND flash is fully, the system startup time is longer....is there a degradation of NAND use that influences the startup time ? Why ? A: Yes - on boot flash abstraction library (old one) read metadata from all sectors to rebuild physical - logical mapping table. davbo-msft (Moderator)[2010-3-30 12:27]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? A: Need addition info on this question. Can you provide more details on what you are trying to do in Silverlight? davbo-msft (Moderator)[2010-3-30 12:27]: Q: If one has an image on a Silverlight page, it seems to be cached. How would one refresh that cache after changing the underlying image? A: Additonal Info: if you want to manually touch the pixels use WriteableBitmap if you want to use the underlying HWND then use IXRVisualHost::GetHWND() davbo-msft (Moderator)[2010-3-30 12:28]: Q: Writable bitmap, is there an example of the syntax? A: if you want to manually touch the pixels use WriteableBitmap if you want to use the underlying HWND then use IXRVisualHost::GetHWND() davbo-msft (Moderator)[2010-3-30 12:29]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? A: Can I get more information about this question about what you are trying to accomplish in Silverlight? davbo-msft (Moderator)[2010-3-30 12:31]: Q: IXRVisualHost::GetHWND() exactly what I needed Thanks, A: Your welcome Sing Wee [MS] (Expert)[2010-3-30 12:31]: Q: ok. thanks for the book's link A: No problem. Travis Hobrla [MS] (Expert)[2010-3-30 12:32]: Q: Typically for SoC devices you name your hardware specific libraries in the form "SOCDIRNAME_LIBNAME". In our platform "OMAP35XX_TPS659XX_TI_V1" if you do this we cause the catalog parser to die... For example if we have a library "Musbfn_OMAP35XX_TPS659XX_TI_V1.dll" entering this in the catalogs pbcxml file in a <module> section causes the XML parser to fail with : Error 3 The 'urn:Microsoft.PlatformBuilder/Catalog:Module' element is        invalid - The value '012345678901234567890123456789.dll' is invalid         according to its datatype         'urn:Microsoft.PlatformBuilder/Catalog:CatalogFileName' - The actual         length is greater than the MaxLength value. A: There are a couple workarounds I can think of. I believe the Module element is only used when doing SYSGEN parsing to make sure dependent SYSGENs are present when the item is selected, so I believe it is optional to the catalog. The other obvious workaround is to shorten the soc name. I realize neither of these solutions is ideal. This is not something we anticipated when we tested CE6.0, sorry. Travis Hobrla [MS] (Expert)[2010-3-30 12:33]: Q: I am getting this error only when I select the KdStub as the debugger in Target device connectivity. A: Right, but KdStub is the debugger that you should use. Have you tried the steps I suggested? Travis Hobrla [MS] (Expert)[2010-3-30 12:36]: Q: If I select Active KTIL, My OS doesn't boots. It says "loading NK.EXE at 0x<xxxxx> location" after that nothing comes in the debug log. A: Can you look at the serial debug output and see what is happening there? Often it can give you a clue to the KITL driver malfunctioning. Travis Hobrla [MS] (Expert)[2010-3-30 12:38]: Q: I have tried that and I am getting the same error. A: I am assuming you have a device created in Target -> Connectivity Options in Platform Builder. What are the Kernel download / Kernel transport for your device? Travis Hobrla [MS] (Expert)[2010-3-30 12:40]: Q: KITL: *** Device Name CEPC56059 *** WARN: KITL will run in polling mode VBridge:: built on [Jul 10 2009] time [10:20:14] VBridgeInit()...TX = [16384] bytes -- Rx = [16384] bytes Tx buffer [0xA1B84860] to [0xA1B88860]. Rx buffer [0xA1B88880] to [0xA1B8C880]. VBridge:: NK add MAC: [0-60-65-2-DA-FB] Connecting to Desktop KITL: Connected host IP: 1 Port: 1086 .. this is the output of the serial debug A: This looks reasonable and does not give clues as to why boot would halt at that point. If you capture a network trace or turn on KITL debug zones via dpCurSettings in kitl.dll, do you see KITL active after this? Travis Hobrla [MS] (Expert)[2010-3-30 12:41]: Q: Both is happening via Ethernet. A: Only thing I have left to suggest is a Platform Builder installation Repair, then. Karel Danihelka [MS] (Expert)[2010-3-30 12:42]: Q: Hi, I saw that the ATADISK is quite generic and des not have any optimizations. Do you have any advice to consider while tryin to improve the performance of it? A: If I remember correctly sample code has support for some specific hardware controllers (little obsolete now). This should be good start point (if you will not decide take existing driver as sample and write you own). Travis Hobrla [MS] (Expert)[2010-3-30 12:44]: Q: I didn't do that. I have to try. A: I think that's the next valid step. You need to figure out whether KITL is hanging or the device - use instrumented serial debug messages and network trace to determine this. Sing Wee [MS] (Expert)[2010-3-30 12:46]: Q: KITL: *** Device Name CEPC56059 *** WARN: KITL will run in polling mode VBridge:: built on [Jul 10 2009] time [10:20:14] VBridgeInit()...TX = [16384] bytes -- Rx = [16384] bytes Tx buffer [0xA1B84860] to [0xA1B88860]. Rx buffer [0xA1B88880] to [0xA1B8C880]. VBridge:: NK add MAC: [0-60-65-2-DA-FB] Connecting to Desktop KITL: Connected host IP: 1 Port: 1086 .. this is the output of the serial debug A: Neo, have you by any chance tried looking into your firewall to see if it might be blocking traffic on any particular ports? Wireshark/netmon might be able to help you here if that's the issue. davbo-msft (Moderator)[2010-3-30 12:48]: Q: I lost spell check, how can i get it back A: Hello - can you give additional details about your question? Is this related to a Windows CE Embedded application? masatos_MSFT (Expert)[2010-3-30 12:51]: Q: When attempting to run the CETK cellcore tests the documentation states the pre-requisites include "stinger.ini", "ltk.ini" but windows CE doesn't provide these or document what they fully need to contain. Implicitly you also need "datatrans.xml" which isn't supplied. If you get around this error and steal these from Windows Mobile instead, when you try and run the CETK tests you get a data abort in radiometricsdll.dll. How should we invoke the cellcore parts of CETK? A: Hi Pev, what version of Windows CE and CETK are you using? I do not have the expertise to answer this question, but can find somebody who can. Travis Hobrla [MS] (Expert)[2010-3-30 12:52]: Q: I don't see a kitlcore.dll in my OS. is my debug image fails to load because of that? A: kitl.dll should be all that's needed, kitlcore.lib is linked into that. Travis Hobrla [MS] (Expert)[2010-3-30 12:55]: Q: I've got a platform (not developed by myself) where I2C bus support has to be provided through the OAL as the kernel needs to talk to devices such as the power management IC and gas gauge so a 'proper' I2C driver hanging off device manager isn't possible. This happens to be a polled driver, so obviously it hits the system hard when either under lots of traffic or an error condition occurs and the driver constantly polls. I originally thought that there was no straightforward way to make such code interrupt driven in the kernel (as it's a cludge) but I realised that that's exactly what ETHDBG drivers do. Is there any reason why I shouldn't have a go at implementing a similar mechanism for our kernel resident I2C driver? If not, are there any obvious pitfalls - I've not seen any other BSP's do this in the past... A: You can make a 'proper' driver that calls down into the OAL to do the actual I2C transactions. Alternatively you can build an interrupt-based version in the OAL where you handle everything in the ISR. There is nothing wrong with that so long as the rest of your drivers and app threads can handle longer times with interrupts off while you are servicing I2C interrupts. Sing Wee [MS] (Expert)[2010-3-30 12:55]: Q: I am having trouble with my mouse, I have the microsoft wireless mobile mouse 3000, when I push the scroll button I am suppose to have autoscroll instead it shows other web pages,Can you help me out tell me what to do!!! A: Sorry, this current chat is about Windows Embedded Compact. Hope you're able to find an answer to your question elsewhere. davbo-msft (Moderator)[2010-3-30 12:56]: Q: Is the Silverlight Animation "Spline" a BezierSpline? A: Spline - http://msdn.microsoft.com/en-us/library/ee501495.aspx<BR< a>>   masatos_MSFT (Expert)[2010-3-30 12:57]: Thanks for the info Pev. I will follow up with the CETK experts here and get back to you. davbo-msft (Moderator)[2010-3-30 12:59]: Q: Spline- bad link A: http://msdn.microsoft.com/en-us/library/ee501495.aspx davbo-msft (Moderator)[2010-3-30 13:0]: Q: Sorry, got to tirm the ">" A: No Worries http://msdn.microsoft.com/en-us/library/ee501495.aspx davbo-msft (Moderator)[2010-3-30 13:0]: Hello everyone, we are just about out of time. Thank you for joining us for our Windows Embedded CE 6.0 chat today! <http://www.Microsoft.com/Embedded>; A special thank you to the product group members for coming out. The transcript of today’s chat will be posted online as soon as possible, to <http://msdn.microsoft.com/en-us/chats>;. We’ll see you again for another chat next month. Please check <http://msdn.microsoft.com/en-us/chats>; for the list of upcoming chats. If you still have unanswered questions, let me suggest that you post them on one of our newsgroups on <http://msdn.microsoft.com/en-us/windowsembedded/ce/default.aspx> -Windows Embedded CE 6.0 R3 Now Available! <http://msdn.microsoft.com/windowsembedded/ce/dd630616.aspx>; davbo-msft (Moderator)[2010-3-30 13:1]: Q: hi everybody. I would like to know if there is something know about a bug in RTC API (VOIP), especially when using SIP. According the to the analysis with application verifyier there is a heap link in rtcdllmedia.dll. All of the unreleased chunks seem to have a size of 6560 bytes. A: I will follow up with the Networking Team for a response. davbo-msft (Moderator)[2010-3-30 13:1]: Q: Hi, we've problems with debugging of applications (= breakpoints in Platform Builder will be ignored) over KITL on Windows CE 5.0, if the PDB files are large (over 60MB). Are there any limitations to size of the PDB files? A: I will follow up with the tools team for a response and post with the transcript. Sing Wee [MS] (Expert)[2010-3-30 13:1]: Q: I am unable to use the target control in my development environment. any ideas? A: Make sure you have SYSGEN_SHELL=1 set in your build environment. davbo-msft (Moderator)[2010-3-30 13:3]: Q: what are the main differences between Object Store and RAM disk ? They are both in RAM...are there performance differences ? access differences ? A: I will follow up with the Core Team and get a response posted with the transcript to MSDN  The Questions   [2010-3-30 12:57]: Thanks for the info Pev. I will follow up with the CETK experts here and get back to you. [2010-3-30 12:59]:   [2010-3-30 13:0]:   [2010-3-30 13:0]: Hello everyone, we are just about out of time. Thank you for joining us for our Windows Embedded CE 6.0 chat today! <http://www.Microsoft.com/Embedded>; A special thank you to the product group members for coming out. The transcript of today’s chat will be posted online as soon as possible, to <http://msdn.microsoft.com/en-us/chats>;. We’ll see you again for another chat next month. Please check <http://msdn.microsoft.com/en-us/chats>; for the list of upcoming chats. If you still have unanswered questions, let me suggest that you post them on one of our newsgroups on <http://msdn.microsoft.com/en-us/windowsembedded/ce/default.aspx> -Windows Embedded CE 6.0 R3 Now Available! <http://msdn.microsoft.com/windowsembedded/ce/dd630616.aspx>; [2010-3-30 13:1]: [2010-3-30 13:1]: [2010-3-30 13:1]: [2010-3-30 13:3]: neo (Guest)[2010-3-30 11:37]: Hi all KellyG (Guest)[2010-3-30 11:37]: Hi KellyG (Guest)[2010-3-30 11:37]: I have a question unrelated to windows Ce embedded, can you please help me?? neo (Guest)[2010-3-30 11:38]: I need to implement hardware timers on my windows CE 6.0 device to trigger events at microsecond intervals! c neo (Guest)[2010-3-30 11:38]: yes. post it. May be i cud give a try KellyG (Guest)[2010-3-30 11:38]: My Product key listed on my tower is not the product key I need for microsoft office, but that is the only product key listed. neo (Guest)[2010-3-30 11:39]: I hope this is a chat for windows embedded. please post ur queries in office forums KellyG (Guest)[2010-3-30 11:39]: it is but i could not find a forum for office neo (Guest)[2010-3-30 11:40]: I think moderators will help u out. @ davbo-msft: can u help this guy? neo (Guest)[2010-3-30 11:41]: Q: I need to implement hardware timers on my windows CE 6.0 device to trigger events at microsecond intervals. Where should i start? davbo-msft (Moderator)[2010-3-30 11:50]: Our chat today covers the topic of Windows Embedded CE! 1. This chat will last for one hour. During this hour, our Experts will respond to as many questions as they can. Please understand that there may be some questions we cannot respond to due to lack of information or because the information is not yet public. 2. We encourage you to submit questions for our Experts. To do so, type your questions in the send box, select the “ask the Experts” box and click SEND. Questions sent directly to the Guest Chat room will not be answered by the Experts, but we encourage other community members to assist. 3. We ask that you stay on topic for the duration of the chat. This helps the Guests and Experts follow the conversation more easily. We invite you to ask off topic questions after this chat is over, but not during. 4. Please abide by the Chat Code of Conduct. Chat code of conduct: <http://msdn.microsoft.com/chats/chatroom.aspx?ctl=hlp#Conduct>; Pev (Guest)[2010-3-30 11:54]: Evening! davbo-msft (Moderator)[2010-3-30 11:54]: Hello everyone this is Dave Boyce - I worked in the Multimedia area for Windows CE. neo (Guest)[2010-3-30 11:55]: hello dave neo (Guest)[2010-3-30 11:55]: The chat code of conduct link is not working! Pev (Guest)[2010-3-30 11:56]: Best be polite just in case then ;-) neo (Guest)[2010-3-30 11:56]: davbo-msft (Moderator)[2010-3-30 11:57]: I'll check out the issue w/ the link paolopat (Guest)[2010-3-30 12:0]: Hello davbo-msft (Moderator)[2010-3-30 12:0]: We are pleased to welcome our Experts for today’s chat. I will have them introduce themselves now. Chat will begin in a couple of minutes. <http://www.Microsoft.com/Embedded>; paolopat (Guest)[2010-3-30 12:3]: Hello Experts ! neo (Guest)[2010-3-30 12:3]: Welcome all! paolopat (Guest)[2010-3-30 12:3]: Q: I want to partition my NAND Flash device. One partition to use for hive ragistry and the other for the apps and data. The only way to do it is programmatically or setting some registry values ? neo (Guest)[2010-3-30 12:3]: Q: I need to implement hardware timers on my windows CE 6.0 device to trigger events at microsecond intervals. Where should i start? neo (Guest)[2010-3-30 12:5]: Q: My CPU is Intel celeron M processor 1Ghz. Pev (Guest)[2010-3-30 12:5]: neo: if your silicon has multiple general purpose timers, pick one that's not in use for the system timer / profiler and set it up to trigger irqs for your purpose. You can't guarantee hard realtime type responses though... GarySwalling (Guest)[2010-3-30 12:5]: Q: Is Windows Phone 7 related to Windows CE? If so, can you tell me what version of Windows CE is the basis? Is it in fact the new version of Windows Mobile? Pev (Guest)[2010-3-30 12:6]: Q: Hi guys, what's the formal way to report bugs back to the core team / product team? The mechanism of calling the support phone number every time is really onerous and time-consuming. Is there another mechanism? paolopat (Guest)[2010-3-30 12:6]: Q: But the operation for creating the partitions ? neo (Guest)[2010-3-30 12:6]: Q: If i need to implement it using interrupt handlers, What are all the files that I should look at? GPM (Guest)[2010-3-30 12:6]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? Jhony (Guest)[2010-3-30 12:7]: Q: I created a OS design with KITL and kernel debugger enabled. But I am unable to connect to the target for debugging. I am getting the following error when i try to connect with the device. PB Debugger Cannot initialize the Kernel Debugger. PB Debugger Debugger could not initialize connection. PB Debugger The Kernel Debugger is waiting to connect with target. PB Debugger The Kernel Debugger has been disconnected successfully. Charles (Guest)[2010-3-30 12:7]: What will be different in Windows Compact 7 from CE 6.0? neo (Guest)[2010-3-30 12:8]: Can I have the book's name please? kiefs_dev (Guest)[2010-3-30 12:8]: Q: hi everybody. I would like to know if there is something know about a bug in RTC API (VOIP), especially when using SIP. According the to the analysis with application verifyier there is a heap link in rtcdllmedia.dll. All of the unreleased chunks seem to have a size of 6560 bytes. paolopat (Guest)[2010-3-30 12:10]: Q: So...I have to modify file system code to create 2 partition at system startup ?!! I haven't understood.... neo (Guest)[2010-3-30 12:10]: Q: Do u mean ISR/IST implementation? How can i register an interrupt? What kind of interrupt should i register? neo (Guest)[2010-3-30 12:11]: Q: Can I have the book's name please? Charles (Guest)[2010-3-30 12:11]: Q: What will be different in Windows Compact 7 from CE 6.0? PaulT (Guest)[2010-3-30 12:11]: neo: I'd say that you really need the docs for YOUR BSP, not generic documents for BSPs in general. Each BSP may be architected differently. If you're using the CEPC BSP, then the documentation that comes with Platform Builder is a reasonable place to look. GPM (Guest)[2010-3-30 12:11]: Q: If one has an image on a Silverlight page, it seems to be cached. How would one refresh that cache after changing the underlying image? Elektrobit (Guest)[2010-3-30 12:12]: Q: Hi, we've problems with debugging of applications (= breakpoints in Platform Builder will be ignored) over KITL on Windows CE 5.0, if the PDB files are large (over 60MB). Are there any limitations to size of the PDB files? Jhony (Guest)[2010-3-30 12:15]: Q: I am using CE 6.0. There is no cesvchost process running in my system. alexquisi (Guest)[2010-3-30 12:15]: Q: Hi, I saw that the ATADISK is quite generic and des not have any optimizations. Do you have any advice to consider while tryin to improve the performance of it? Jhony (Guest)[2010-3-30 12:17]: Windows XP service pack 1 Jhony (Guest)[2010-3-30 12:17]: Q: sorry! Windows XP SP3 neo (Guest)[2010-3-30 12:19]: Q: The link for developing device drivers is not working. can u please check that? paolopat (Guest)[2010-3-30 12:20]: Q: I have a NAND Flash on my target device. On this flash I have the hive registry and an application.I have observed that when the NAND flash is fully, the system startup time is longer....is there a degradation of NAND use that influences the startup time ? Why ? Pev (Guest)[2010-3-30 12:20]: Q: When attempting to run the CETK cellcore tests the documentation states the pre-requisites include "stinger.ini", "ltk.ini" but windows CE doesn't provide these or document what they fully need to contain. Implicitly you also need "datatrans.xml" which isn't supplied. If you get around this error and steal these from Windows Mobile instead, when you try and run the CETK tests you get a data abort in radiometricsdll.dll. How should we invoke the cellcore parts of CETK? Pev (Guest)[2010-3-30 12:21]: Hi all, Pev (Guest)[2010-3-30 12:21]: oops Pev (Guest)[2010-3-30 12:21]: :-D Pev (Guest)[2010-3-30 12:24]: Typically for SoC devices you name your hardware specific libraries in the form "SOCDIRNAME_LIBNAME". In our platform "OMAP35XX_TPS659XX_TI_V1" if you do this we cause the catalog parser to die... For example if we have a library "Musbfn_OMAP35XX_TPS659XX_TI_V1.dll" entering this in the catalogs pbcxml file in a <module> section causes the XML parser to fail with : Pev (Guest)[2010-3-30 12:25]: Q: Error 3 The 'urn:Microsoft.PlatformBuilder/Catalog:Module' element is        invalid - The value '012345678901234567890123456789.dll' is invalid         according to its datatype         'urn:Microsoft.PlatformBuilder/Catalog:CatalogFileName' - The actual         length is greater than the MaxLength value. GPM (Guest)[2010-3-30 12:25]: Q: Writable bitmap, is there an example of the syntax? Pev (Guest)[2010-3-30 12:25]: Q: Typically for SoC devices you name your hardware specific libraries in the form "SOCDIRNAME_LIBNAME". In our platform "OMAP35XX_TPS659XX_TI_V1" if you do this we cause the catalog parser to die... For example if we have a library "Musbfn_OMAP35XX_TPS659XX_TI_V1.dll" entering this in the catalogs pbcxml file in a <module> section causes the XML parser to fail with : Error 3 The 'urn:Microsoft.PlatformBuilder/Catalog:Module' element is        invalid - The value '012345678901234567890123456789.dll' is invalid         according to its datatype         'urn:Microsoft.PlatformBuilder/Catalog:CatalogFileName' - The actual         length is greater than the MaxLength value. Pev (Guest)[2010-3-30 12:25]: sorry, messed up submission there! GPM (Guest)[2010-3-30 12:26]: Q: I would like to get a handle to a Silverlight screen section, is that possiable? GPM (Guest)[2010-3-30 12:28]: Q: IXRVisualHost::GetHWND() exactly what I needed Thanks, PaulT (Guest)[2010-3-30 12:29]: GPM: You don't have to keep submitting the questions. The chat experts have an application that they're using to follow the chat and all Ask the Experts questions are logged. Jhony (Guest)[2010-3-30 12:29]: Q: I am getting this error only when I select the KdStub as the debugger in Target device connectivity. neo (Guest)[2010-3-30 12:30]: Q: ok. thanks for the book's link Pev (Guest)[2010-3-30 12:31]: Hm, did those two I submitted get picked up by anyone? neo (Guest)[2010-3-30 12:33]: Q: If I select Active KTIL, My OS doesn't boots. It says "loading NK.EXE at 0x<xxxxx> location" after that nothing comes in the debug log. PaulT (Guest)[2010-3-30 12:34]: Pev: PaulT (Guest)[2010-3-30 12:35]: Pev: I'm sure they did. The guys who are actually on the chat may not be experts in that part of things. That's usually the explanation when you don't get an answer in 10 minutes or so. Pev (Guest)[2010-3-30 12:36]: Ah, fair enough Susie (Guest)[2010-3-30 12:36]: My Outlook Express incoming mail is corrput. No ONE has been able to fix the problem, Dell or Norton. I have dial up I'm in a rural area Jhony (Guest)[2010-3-30 12:37]: Q: I have tried that and I am getting the same error. Pev (Guest)[2010-3-30 12:37]: Susie : Use Thunderbird instead :-D PaulT (Guest)[2010-3-30 12:37]: Susie: Sorry, but this chat is not about Windows, but Embedded (like what runs on a phone). Your best chance is to find a local expert or talk to your ISP. paolopat (Guest)[2010-3-30 12:37]: Q: what are the main differences between Object Store and RAM disk ? They are both in RAM...are there performance differences ? access differences ? Susie (Guest)[2010-3-30 12:38]: My computer knowlege is very limited, what is Thunderbird? Pev (Guest)[2010-3-30 12:38]: A different email client :-D neo (Guest)[2010-3-30 12:39]: Q: KITL: *** Device Name CEPC56059 *** WARN: KITL will run in polling mode VBridge:: built on [Jul 10 2009] time [10:20:14] VBridgeInit()...TX = [16384] bytes -- Rx = [16384] bytes Tx buffer [0xA1B84860] to [0xA1B88860]. Rx buffer [0xA1B88880] to [0xA1B8C880]. VBridge:: NK add MAC: [0-60-65-2-DA-FB] Connecting to Desktop KITL: Connected host IP: 1 Port: 1086 .. this is the output of the serial debug Susie (Guest)[2010-3-30 12:39]: Do I need to uninstall Outlook Express youngboyzie (Guest)[2010-3-30 12:39]: I need to start battery calibration for my new battery for my dell inspiron 1525 laptop and should be able to reach the BIOS screen by hitting f2 but this isnt working... help? Pev (Guest)[2010-3-30 12:39]: Nah, you can run it instead - you'll still need help from your ISP to configure it I expect Jhony (Guest)[2010-3-30 12:39]: Q: Both is happening via Ethernet. PaulT (Guest)[2010-3-30 12:40]: youngboyzie: You're off-topic. This is not a general chat for Windows and certainly not for Dell. You'll have to ask Dell how to get to setup; it's their machine. bill (Guest)[2010-3-30 12:41]: I lost spell check, how can i get et back neo (Guest)[2010-3-30 12:42]: Q: I didn't do that. I have to try. Jhony (Guest)[2010-3-30 12:43]: Q: Ok. I will do it then. bill (Guest)[2010-3-30 12:43]: Q: I lost spell check, how can i get it back PaulT (Guest)[2010-3-30 12:44]: bill: This isn't a general Windows chat. There are some Web forums that you might try. GarySwalling (Guest)[2010-3-30 12:45]: Q: Thanks, I found the Phone 7 presentation at http://live.visitmix.com/MIX10/Sessions/CL13 GPM (Guest)[2010-3-30 12:45]: Q: Is the Silverlight Animation "Spline" a BezierSpline? neo (Guest)[2010-3-30 12:46]: Q: ok. I'll do it. thanks Pev (Guest)[2010-3-30 12:46]: Whowever was asking about KITL connection : I've had this loads in the past. I think I started debugging last time by using wireshark to see what was happening on the network then setting up the OAL_ETHER and OAL_FUNC and OAL_VERBOSE as well as OAL_KITL flags to see what was actually happening in the driver.... Pev (Guest)[2010-3-30 12:47]: I'd generally make sure that you're testing though a 10baseT hub (instead of anything faster) and forcing Active KITL in polled mode too... neo (Guest)[2010-3-30 12:48]: Q: I disabled the firewall in my PC. Pev (Guest)[2010-3-30 12:50]: Q: I've got a platform (not developed by myself) where I2C bus support has to be provided through the OAL as the kernel needs to talk to devices such as the power management IC and gas gauge so a 'proper' I2C driver hanging off device manager isn't possible. This happens to be a polled driver, so obviously it hits the system hard when either under lots of traffic or an error condition occurs and the driver constantly polls. I originally thought that there was no straightforward way to make such code interrupt driven in the kernel (as it's a cludge) but I realised that that's exactly what ETHDBG drivers do. Is there any reason why I shouldn't have a go at implementing a similar mechanism for our kernel resident I2C driver? If not, are there any obvious pitfalls - I've not seen any other BSP's do this in the past... neo (Guest)[2010-3-30 12:51]: Q: I don't see a kitlcore.dll in my OS. is my debug image fails to load because of that? Pev (Guest)[2010-3-30 12:52]: Q: Hi masatos, I'm using Windows Embedded CE 6.0 with R3 and patched to feb 2010's QFE's (with it's associated CETK version) this is a machine with only CE 6.0 on (no conflicts with earlier CE or WM...) neo (Guest)[2010-3-30 12:54]: ok. Got it neo (Guest)[2010-3-30 12:54]: Q: ok. Got it Roundman (Guest)[2010-3-30 12:55]: Q: I am having trouble with my mouse, I have the microsoft wireless mobile mouse 3000, when I push the scroll button I am suppose to have autoscroll instead it shows other web pages,Can you help me out tell me what to do!!! Pev (Guest)[2010-3-30 12:55]: Hey neo, debugging kitl issues is really frustrating but dont lose heart :-) neo (Guest)[2010-3-30 12:55]: @ pev : u fixed the problem of KITL after that? neo (Guest)[2010-3-30 12:56]: I am getting the same error again and again. I even cleaned my environment and tried in a fresh PC. But didn't succeed yet Pev (Guest)[2010-3-30 12:56]: Well, eventually - my experiences probably won't help you as different platforms have different reasons for doing that neo (Guest)[2010-3-30 12:56]: I think so PaulT (Guest)[2010-3-30 12:58]: neo: Have you searched the old messages in microsoft.public.windowsce.platbuilder? It seems to me that there was a packet size situation where it was possible to have problems with KITL connections based on a setting on the PC. Google Groups, groups.google.com, Advanced Groups Search will allow you to search a single newsgroup or a set of newsgroups easily. GPM (Guest)[2010-3-30 12:58]: Q: Spline- bad link PaulT (Guest)[2010-3-30 12:58]: GPM: without the > at the end does it work? It seems to for me... neo (Guest)[2010-3-30 12:58]: But some times if i try to connect to the device again. The Image information is seen in the serial debug. what does that mean?Download BIN file information: ----------------------------------------------------- [0]: Base Address=0x220000 Length=0x18DAADC Received a broadcast message !CheckUDP: Not UDP (proto = 0x00000001) after this i am getting the old errors. PB debugger cannot initialize ... GPM (Guest)[2010-3-30 12:59]: Q: Sorry, got to tirm the ">" neo (Guest)[2010-3-30 12:59]: ok paul. I ll look into that. davbo-msft (Moderator)[2010-3-30 13:0]: Hello everyone, we are just about out of time. Thank you for joining us for our Windows Embedded CE 6.0 chat today! <http://www.Microsoft.com/Embedded>; A special thank you to the product group members for coming out. The transcript of today’s chat will be posted online as soon as possible, to <http://msdn.microsoft.com/en-us/chats>;. We’ll see you again for another chat next month. Please check <http://msdn.microsoft.com/en-us/chats>; for the list of upcoming chats. If you still have unanswered questions, let me suggest that you post them on one of our newsgroups on <http://msdn.microsoft.com/en-us/windowsembedded/ce/default.aspx> -Windows Embedded CE 6.0 R3 Now Available! <http://msdn.microsoft.com/windowsembedded/ce/dd630616.aspx>; neo (Guest)[2010-3-30 13:1]: Q: I am unable to use the target control in my development environment. any ideas? Pev (Guest)[2010-3-30 13:1]: Sure, if KITL isn't connected target control won't work as it runs over kitl... neo (Guest)[2010-3-30 13:1]: ok .thanks pev neo (Guest)[2010-3-30 13:2]: yes. sysgen_shell is set to 1 neo (Guest)[2010-3-30 13:2]: Q: yes. sysgen_shell is set to 1 Marcelovk (Guest)[2010-3-30 13:2]: Q: Is there any way to extract the default command lines of the tests in CETK? I want to have it running unconnected from the desktop.   Copyright © 2010 – Bruce Eitman All Rights Reserved

    Read the article

  • Big Data – Buzz Words: What is MapReduce – Day 7 of 21

    - by Pinal Dave
    In yesterday’s blog post we learned what is Hadoop. In this article we will take a quick look at one of the four most important buzz words which goes around Big Data – MapReduce. What is MapReduce? MapReduce was designed by Google as a programming model for processing large data sets with a parallel, distributed algorithm on a cluster. Though, MapReduce was originally Google proprietary technology, it has been quite a generalized term in the recent time. MapReduce comprises a Map() and Reduce() procedures. Procedure Map() performance filtering and sorting operation on data where as procedure Reduce() performs a summary operation of the data. This model is based on modified concepts of the map and reduce functions commonly available in functional programing. The library where procedure Map() and Reduce() belongs is written in many different languages. The most popular free implementation of MapReduce is Apache Hadoop which we will explore tomorrow. Advantages of MapReduce Procedures The MapReduce Framework usually contains distributed servers and it runs various tasks in parallel to each other. There are various components which manages the communications between various nodes of the data and provides the high availability and fault tolerance. Programs written in MapReduce functional styles are automatically parallelized and executed on commodity machines. The MapReduce Framework takes care of the details of partitioning the data and executing the processes on distributed server on run time. During this process if there is any disaster the framework provides high availability and other available modes take care of the responsibility of the failed node. As you can clearly see more this entire MapReduce Frameworks provides much more than just Map() and Reduce() procedures; it provides scalability and fault tolerance as well. A typical implementation of the MapReduce Framework processes many petabytes of data and thousands of the processing machines. How do MapReduce Framework Works? A typical MapReduce Framework contains petabytes of the data and thousands of the nodes. Here is the basic explanation of the MapReduce Procedures which uses this massive commodity of the servers. Map() Procedure There is always a master node in this infrastructure which takes an input. Right after taking input master node divides it into smaller sub-inputs or sub-problems. These sub-problems are distributed to worker nodes. A worker node later processes them and does necessary analysis. Once the worker node completes the process with this sub-problem it returns it back to master node. Reduce() Procedure All the worker nodes return the answer to the sub-problem assigned to them to master node. The master node collects the answer and once again aggregate that in the form of the answer to the original big problem which was assigned master node. The MapReduce Framework does the above Map () and Reduce () procedure in the parallel and independent to each other. All the Map() procedures can run parallel to each other and once each worker node had completed their task they can send it back to master code to compile it with a single answer. This particular procedure can be very effective when it is implemented on a very large amount of data (Big Data). The MapReduce Framework has five different steps: Preparing Map() Input Executing User Provided Map() Code Shuffle Map Output to Reduce Processor Executing User Provided Reduce Code Producing the Final Output Here is the Dataflow of MapReduce Framework: Input Reader Map Function Partition Function Compare Function Reduce Function Output Writer In a future blog post of this 31 day series we will explore various components of MapReduce in Detail. MapReduce in a Single Statement MapReduce is equivalent to SELECT and GROUP BY of a relational database for a very large database. Tomorrow In tomorrow’s blog post we will discuss Buzz Word – HDFS. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

    Read the article

  • 5 Steps to getting started with IronRuby

    - by Eric Nelson
    IronRuby is a Open Source implementation of the Ruby programming language for .NET, heavily relying on Microsoft's Dynamic Language Runtime. The project's #1 goal is to be a true Ruby implementation, meaning it runs existing Ruby code. Check out this summary of using the Ruby standard library and 3rd party libraries in IronRuby. IronRuby has tight integration with .NET, so any .NET types can be used from IronRuby and the IronRuby runtime can be embedded into any .NET application. These 5 steps should get you nicely up and running on IronRuby – OR … you could just watch a video session from the lead developer which took place earlier this month (March 2010 - 60mins). But the 5 steps will be quicker :-) Step 1 – Install IronRuby :-) You can install IronRuby automatically using an MSI or manually. For simplicity I would recommend the MSI install. TIP: As of the 25th of March IronRuby has not quite shipped. The download above is a Release Candidate (RC) which means it is still undergoing final testing by the team. You will need to uninstall this version (RC3) once the final release is available. The good news is that uninstalling IronRuby RC3 will work without a hitch as the MSI does relatively little. Step 2 – Install an IronRuby friendly editor You will need to Install an editor to work with IronRuby as there is no designer support for IronRuby inside Visual Studio. There are many editors to choose from but I would recommend you either went with: SciTE (Download the MSI): This is a lightweight text editor which is simple to get up and running. SciTE understands Ruby syntax and allows you to easily run IronRuby code within the editor with a small change to the config file. SharpDevelop 3.2 (Download the MSI): This is an open source development environment for C#, VB, Boo and now IronRuby. IronRuby support is new but it does include integrated debugging. You might also want to check out the main site for SharpDevelop. TIP: There are commercial tools for Ruby development which offer richer support such as intellisense.. They can be coerced into working with IronRuby. A good one to start with is RubyMine which needs some small changes to make it work with IronRuby. Step 3 – Run the IronRuby Tutorial Run through the IronRuby tutorial which is included in the IronRuby download. It covers off the basics of the Ruby languages and how IronRuby integrates with .NET. In a typical install it will end up at C:\Program Files\IronRuby 0.9.4.0\Samples\Tutorial. Which will give you the tutorial implemented in .NET and Ruby. TIP: You might also want to check out these two introductory posts Using IronRuby and .NET to produce the ‘Hello World of WPF’ and What's IronRuby, and how do I put it on Rails? Step 4 – Get some good books to read Get a great book on Ruby and IronRuby. There are several free ebooks on Ruby which will help you learn the language. The little book of Ruby is a good place to start. I would also recommend you purchase IronRuby Unleashed (Buy on Amazon UK | Buy on Amazon USA). You might also want to check out this mini-review. Other books are due out soon including IronRuby in Action. TIP: Also check out the official documentation for using .NET from IronRuby. Step 5 – Keep an eye on the team blogs Keep an eye on the IronRuby team blogs including Jimmy Schementi, Jim Deville and Tomas Matousek (full list) TIP: And keep a watch out for the final release of IronRuby – due anytime soon!

    Read the article

  • Text Expansion Awareness for UX Designers: Points to Consider

    - by ultan o'broin
    Awareness of translated text expansion dynamics is important for enterprise applications UX designers (I am assuming all source text for translation is in English, though apps development can takes place in other natural languages too). This consideration goes beyond the standard 'character multiplication' rule and must take into account the avoidance of other layout tricks that a designer might be tempted to try. Follow these guidelines. For general text expansion, remember the simple rule that the shorter the word is in the English, the longer it will need to be in English. See the examples provided by Richard Ishida of the W3C and you'll get the idea. So, forget the 30 percent or one inch minimum expansion rule of the old Forms days. Unfortunately remembering convoluted text expansion rules, based as a percentage of the US English character count can be tough going. Try these: Up to 10 characters: 100 to 200% 11 to 20 characters: 80 to 100% 21 to 30 characters: 60 to 80% 31 to 50 characters: 40 to 60% 51 to 70 characters: 31 to 40% Over 70 characters: 30% (Source: IBM) So it might be easier to remember a rule that if your English text is less than 20 characters then allow it to double in length (200 percent), and then after that assume an increase by half the length of the text (50%). (Bear in mind that ADF can apply truncation rules on some components in English too). (If your text is stored in a database, developers must make sure the table column widths can accommodate the expansion of your text when translated based on byte size for the translated character and not numbers of characters. Use Unicode. One character does not equal one byte in the multilingual enterprise apps world.) Rely on a graceful transformation of translated text. Let all pages to resize dynamically so the text wraps and flow naturally. ADF pages supports this already. Think websites. Don't hard-code alignments. Use Start and End properties on components and not Left or Right. Don't force alignments of components on the page by using texts of a certain length as spacers. Use proper label positioning and anchoring in ADF components or other technologies. Remember that an increase in text length means an increase in vertical space too when pages are resized. So don't hard-code vertical heights for any text areas. Don't be tempted to manually create text or printed reports this way either. They cannot be translated successfully, and are very difficult to maintain in English. Use XML, HTML, RTF and so on. Check out what Oracle BI Publisher offers. Don't force wrapping by using tricks such as /n or /t characters or HTML BR tags or forced page breaks. Once the text is translated the alignment will be destroyed. The position of the breaking character or tag would need to be moved anyway, or even removed. When creating tables, then use table components. Don't use manually created tables that reply on word length to maintain column and row alignment. For example, don't use codeblock elements in HTML; use the proper table elements instead. Once translated, the alignment of manually formatted tabular data is destroyed. Finally, if there is a space restriction, then don't use made-up acronyms, abbreviations or some form of daft text speak to save space. Besides being incomprehensible in English, they may need full translations of the shortened words, even if they can be figured out. Use approved or industry standard acronyms according to the UX style rules, not as a space-saving device. Restricted Real Estate on Mobile Devices On mobile devices real estate is limited. Using shortened text is fine once it is comprehensible. Users in the mobile space prefer brevity too, as they are on the go, performing three-minute tasks, with no time to read lengthy texts. Using fragments and lightning up on unnecessary articles and getting straight to the point with imperative forms of verbs makes sense both on real estate and user experience grounds.

    Read the article

  • Principles of Big Data By Jules J Berman, O&rsquo;Reilly Media Book Review

    - by Compudicted
    Originally posted on: http://geekswithblogs.net/Compudicted/archive/2013/11/04/principles-of-big-data-by-jules-j-berman-orsquoreilly-media.aspx A fantastic book! Must be part, if not yet, of the fundamentals of the Big Data as a field of science. Highly recommend to those who are into the Big Data practice. Yet, I confess this book is one of my best reads this year and for a number of reasons: The book is full of wisdom, intimate insight, historical facts and real life examples to how Big Data projects get conceived, operate and sadly, yes, sometimes die. But not only that, the book is most importantly is filled with valuable advice, accurate and even overwhelming amount of reference (from the positive side), and the author does not event stop there: there are numerous technical excerpts, links and examples allowing to quickly accomplish many daunting tasks or make you aware of what one needs to perform as a data practitioner (excuse my use of the word practitioner, I just did not find a better substitute to it to trying to reference all who face Big Data). Be aware that Jules Berman’s background is in medicine, naturally, this book discusses this subject a lot as it is very dear to the author’s heart I believe, this does not make this book any less significant however, quite the opposite, I trust if there is an area in science or practice where the biggest benefits can be ripped from Big Data projects it is indeed the medical science, let’s make Cancer history! On a personal note, for me as a database, BI professional it has helped to understand better the motives behind Big Data initiatives, their underwater rivers and high altitude winds that divert or propel them forward. Additionally, I was impressed by the depth and number of mining algorithms covered in it. I must tell this made me very curious and tempting to find out more about these indispensable attributes of Big Data so sure I will be trying stretching my wallet to acquire several books that go more in depth on several most popular of them. My favorite parts of the book, well, all of them actually, but especially chapter 9: Analysis, it is just very close to my heart. But the real reason is it let me see what I do with data from a different angle. And then the next - “Special Considerations”, they are just two logical parts. The writing language is of this book is very acceptable for all levels, I had no technical problem reading it in ebook format on my 8” tablet or a large screen monitor. If I would be asked to say at least something negative I have to state I had a feeling initially that the book’s first part reads like an academic material relaxing the reader as the book progresses forward. I admit I am impressed with Jules’ abilities to use several programming languages and OSS tools, bravo! And I agree, it is not too, too hard to grasp at least the principals of a modern programming language, which seems becomes a defacto knowledge standard item for any modern human being. So grab a copy of this book, read it end to end and make yourself shielded from making mistakes at any stage of your Big Data initiative, by the way this book also helps build better future Big Data projects. Disclaimer: I received a free electronic copy of this book as part of the O'Reilly Blogger Program.

    Read the article

  • shell script over SSH ends unexpectedly after running 'ant build'

    - by YShin
    I wrote a shell script that runs on remote host to build source code with 'ant build' command, and then distribute the built binary to other servers. However, right after Ant build is over successfully(I can see the command line output saying Build was successful), the ssh session ends and whatever commands after 'ant build' does not get executed. I'm confused what might be cause of this behavior. I suspected that it might be because the 'ant build' command takes too long time, and SSH somehow quits itself after that long command. But I don't think that's correct since if I just do 'sleep 60' in place of 'ant build' command, it actually execute latter commands as intended. I'm new at shell programming, so I might have made some silly misassumption. Can someone provide a pointer to a possible cause of this problem? My shell script #!/bin/bash # Inject some variables ssh -T $SSH_USER@$SSH_URL "setenv REMOTE_BASE_DIR $REMOTE_BASE_DIR; setenv CASSANDRA_SRC_TAR_FILE $CASSANDRA_SRC_TAR_FILE; setenv CASSANDRA_SRC_DIR_NAME $CASSANDRA_SRC_DIR_NAME; setenv CLUSTER_SIZE $CLUSTER_SIZE; setenv REMOTE_REDEPLOY_SCRIPT $REMOTE_REDEPLOY_SCRIPT; /bin/bash" << 'EOF' export JAVA_HOME=/usr/lib/jvm/jdk1.7.0 cd $REMOTE_BASE_DIR/$CASSANDRA_SRC_DIR_NAME echo "## Building Cassandra source" ant clean build # Anything after this doesn't run echo "## Ant Build is over. Invoking redeploy script on remote nodes" # Invoke redeploy script for each node for (( i=0; i < CLUSTER_SIZE; i++)) do echo "## Invoking redeploy script on node-$i" done Command-line output ## Building Cassandra source Buildfile: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build.xml clean: [delete] Deleting directory /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/test [delete] Deleting directory /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes [delete] Deleting directory /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/gen-java [delete] Deleting directory /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/resources/org/apache/cassandra/config init: [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes/main [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes/thrift [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/test/lib [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/test/classes [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/gen-java maven-ant-tasks-localrepo: maven-ant-tasks-download: maven-ant-tasks-init: maven-declare-dependencies: maven-ant-tasks-retrieve-build: init-dependencies: [echo] Loading dependency paths from file: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/build-dependencies.xml check-gen-cli-grammar: gen-cli-grammar: [echo] Building Grammar /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/java/org/apache/cassandra/cli/Cli.g .... check-gen-cql2-grammar: gen-cql2-grammar: [echo] Building Grammar /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/java/org/apache/cassandra/cql/Cql.g ... check-gen-cql3-grammar: gen-cql3-grammar: [echo] Building Grammar /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/java/org/apache/cassandra/cql3/Cql.g ... build-project: [echo] apache-cassandra: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build.xml [javac] Compiling 43 source files to /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes/thrift [javac] Note: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/interface/thrift/gen-java/org/apache/cassandra/thrift/Cassandra.java uses or overrides a deprecated API. [javac] Note: Recompile with -Xlint:deprecation for details. [javac] Note: Some input files use unchecked or unsafe operations. [javac] Note: Recompile with -Xlint:unchecked for details. [javac] Compiling 865 source files to /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes/main [javac] Note: Some input files use or override a deprecated API. [javac] Note: Recompile with -Xlint:deprecation for details. [javac] Note: Some input files use unchecked or unsafe operations. [javac] Note: Recompile with -Xlint:unchecked for details. createVersionPropFile: [mkdir] Created dir: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/resources/org/apache/cassandra/config [propertyfile] Creating new property file: /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/src/resources/org/apache/cassandra/config/version.properties [copy] Copying 3 files to /scratch/ISS/shin14/repos/apache-cassandra-2.0.8-src-0713/build/classes/main build: BUILD SUCCESSFUL Total time: 32 seconds

    Read the article

< Previous Page | 212 213 214 215 216 217 218 219 220 221 222 223  | Next Page >