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  • Unrealscript splitting a string

    - by burntsugar
    Note, this is repost from stackoverflow - I have only just discovered this site :) I need to split a string in Unrealscript, in the same way that Java's split function works. For instance - return the string "foo" as an array of char. I have tried to use the SplitString function: array SplitString( string Source, optional string Delimiter=",", optional bool bCullEmpty ) Wrapper for splitting a string into an array of strings using a single expression. as found at http://udn.epicgames.com/Three/UnrealScriptFunctions.html but it returns the entire String. simulated function wordDraw() { local String inputString; inputString = "trolls"; local string whatwillitbe; local int b; local int x; local array<String> letterArray; letterArray = SplitString(inputString,, false); for (x = 0; x < letterArray.Length; x++) { whatwillitbe = letterArray[x]; `log('it will be '@whatwillitbe); b = letterarray.Length; `log('letterarray length is '@b); `log('letter number '@x); } } Output is: b returns: 1 whatwillitbe returns: trolls However I would like b to return 6 and whatwillitbe to return each character individually. I have had a few answers proposed, however, I would still like to properly understand how the SplitString function works. For instance, if the Delimiter parameter is optional, what does the function use as a delimiter by default?

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  • Getting an OBB out of another OBB?

    - by Milo
    I'm working on collision resolution for my game. I just need a good way to get an object out of another object if it gets stuck. In this case a car. Here is a typical scenario. The red car is in the green object. How do I correctly get it out so the car can slide along the edge of the object as it should. I tried: if(buildings.size() > 0) { Entity e = buildings.get(0); Vector2D vel = new Vector2D(); vel.x = vehicle.getVelocity().x; vel.y = vehicle.getVelocity().y; vel.normalize(); while(vehicle.getRect().overlaps(e.getRect())) { vehicle.setCenter(vehicle.getCenterX() - vel.x * 0.1f, vehicle.getCenterY() - vel.y * 0.1f); } colided = true; } But that does not work too well. Is there some sort of vector I could calculate to use as the vector to move the car away from the object? Thanks

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  • Using PowerShell, in Active Direcotry, how would I change all the DNS A records that have a given IP to a new IP?

    - by djsumdog
    We've been moving data centers and I have a lot of old records that were not correctly but in DNS as CNAME records, but A records that have a direct IP (e.g. 192.168.100.n) and they're all moving to a new subnet (10.19.100.n). I just need to write a powershell script to change all those records. I found this site: http://www.indented.co.uk/index.php/2008/12/30/administering-microsoft-dns-in-powershell/ and from it I made this simple script: $dnsServer = "meldc2" $scope = New-Object Management.ManagementScope("\\$dnsServer\root\MicrosoftDNS") $path = New-Object Management.ManagementPath("MicrosoftDNS_Zone") $options = New-Object Management.ObjectGetOptions($Null,[System.TimeSpan]::MaxValue, $True) $ZoneClass= New-Object Management.ManagementClass($scope,$path,$options) $Zones = Get-WMIObject -Computer $dnsServer -Namespace "root\MicrosoftDNS" -Class "MicrosoftDNS_Zone" $Zones | Get-Member foreach($Z in $Zones) { $Z | Select-Object Name,DsIntegrated,ZoneType,Reverse,Data } but that only gets me a listing of root zones. I don't understand how to iterate over all the entries in each of the zones. Also, all the examples I've seen involve adding new zones, but there aren't any examples I can find on modifying existing A records.

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  • What are good reasons to use explicit interface implementation for the sole purpose of hiding members?

    - by Nathanus
    During one of my studies into the intricacies of C#, I came across an interesting passage concerning explicit interface implementation. While this syntax is quite helpful when you need to resolve name clashes, you can use explicit interface implementation simply to hide more "advanced" members from the object level. The difference between allowing the use of object.method() or requiring the casting of ((Interface)object).method() seems like mean-spirited obfuscation to my inexperienced eyes. The text noted that this will hide the method from Intellisense at the object level, but why would you want to do that if it was not necessary to avoid name conflicts?

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  • Best Creational Pattern for loggers in a multi-threaded system?

    - by Dipan Mehta
    This is a follow up question on my past questions : Concurrency pattern of logger in multithreaded application As suggested by others, I am putting this question separately. As the learning from the last question. In a multi-threaded environment, the logger should be made thread safe and probably asynchronous (where in messages are queued while a background thread does writing releasing the requesting object thread). The logger could be signleton or it can be a per-group logger which is a generalization of the above. Now, the question that arise is how does logger should be assigned to the object? There are two options I can think of: 1. Object requesting for the logger: Should each of the object call some global API such as get_logger()? Such an API returns "the" singleton or the group logger. However, I feel this involves assumption about the Application environment to implement the logger -which I think is some kind of coupling. If the same object needs to be used by other application - this new application also need to implement such a method. 2. Assign logger through some known API The other alternative approach is to create a kind of virtual class which is implemented by application based on App's own structure and assign the object sometime in the constructor. This is more generalized method. Unfortunately, when there are so many objects - and rather a tree of objects passing on the logger objects to each level is quite messy. My question is there a better way to do this? If you need to pick any one of the above, which approach is would you pick and why? Other questions remain open about how to configure them: How do objects' names or ID are assigned so that will be used for printing on the log messages (as the module names) How do these objects find the appropriate properties (such as log levels, and other such parameters) In the first approach, the central API needs to deal with all this varieties. In the second approach - there needs to be additional work. Hence, I want to understand from the real experience of people, as to how to write logger effectively in such an environment.

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  • Passing Strings by Ref

    - by SGWellens
    Humbled yet again…DOH! No matter how much experience you acquire, no matter how smart you may be, no matter how hard you study, it is impossible to keep fully up to date on all the nuances of the technology we are exposed to. There will always be gaps in our knowledge: Little 'dead zones' of uncertainty. For me, this time, it was about passing string parameters to functions. I thought I knew this stuff cold. First, a little review... Value Types and Ref Integers and structs are value types (as opposed to reference types). When declared locally, their memory storage is on the stack; not on the heap. When passed to a function, the function gets a copy of the data and works on the copy. If a function needs to change a value type, you need to use the ref keyword.  Here's an example:     // ---- declaration -----------------     public struct MyStruct    {        public string StrTag;    }     // ---- functions -----------------------     void SetMyStruct(MyStruct myStruct)     // pass by value    {        myStruct.StrTag = "BBB";    }     void SetMyStruct(ref MyStruct myStruct)  // pass by ref    {        myStruct.StrTag = "CCC";    }     // ---- Usage -----------------------     protected void Button1_Click(object sender, EventArgs e)    {        MyStruct Data;        Data.StrTag = "AAA";         SetMyStruct(Data);        // Data.StrTag is still "AAA"         SetMyStruct(ref Data);        // Data.StrTag is now "CCC"    } No surprises here. All value types like ints, floats, datetimes, enums, structs, etc. work the same way. And now on to... Class Types and Ref     // ---- Declaration -----------------------------     public class MyClass    {        public string StrTag;    }     // ---- Functions ----------------------------     void SetMyClass(MyClass myClass)  // pass by 'value'    {        myClass.StrTag = "BBB";    }     void SetMyClass(ref MyClass myClass)   // pass by ref    {        myClass.StrTag = "CCC";    }     // ---- Usage ---------------------------------------     protected void Button2_Click(object sender, EventArgs e)    {        MyClass Data = new MyClass();        Data.StrTag = "AAA";         SetMyClass(Data);          // Data.StrTag is now "BBB"         SetMyClass(ref Data);        // Data.StrTag is now "CCC"    }  No surprises here either. Since Classes are reference types, you do not need the ref keyword to modify an object. What may seem a little strange is that with or without the ref keyword, the results are the same: The compiler knows what to do. So, why would you need to use the ref keyword when passing an object to a function? Because then you can change the reference itself…ie you can make it refer to a completely different object. Inside the function you can do: myClass = new MyClass() and the old object will be garbage collected and the new object will be returned to the caller. That ends the review. Now let's look at passing strings as parameters. The String Type and Ref Strings are reference types. So when you pass a String to a function, you do not need the ref keyword to change the string. Right? Wrong. Wrong, wrong, wrong. When I saw this, I was so surprised that I fell out of my chair. Getting up, I bumped my head on my desk (which really hurt). My bumping the desk caused a large speaker to fall off of a bookshelf and land squarely on my big toe. I was screaming in pain and hopping on one foot when I lost my balance and fell. I struck my head on the side of the desk (once again) and knocked myself out cold. When I woke up, I was in the hospital where due to a database error (thanks Oracle) the doctors had put casts on both my hands. I'm typing this ever so slowly with just my ton..tong ..tongu…tongue. But I digress. Okay, the only true part of that story is that I was a bit surprised. Here is what happens passing a String to a function.     // ---- Functions ----------------------------     void SetMyString(String myString)   // pass by 'value'    {        myString = "BBB";    }     void SetMyString(ref String myString)  // pass by ref    {        myString = "CCC";    }     // ---- Usage ---------------------------------     protected void Button3_Click(object sender, EventArgs e)    {        String MyString = "AAA";         SetMyString(MyString);        // MyString is still "AAA"  What!!!!         SetMyString(ref MyString);        // MyString is now "CCC"    } What the heck. We should not have to use the ref keyword when passing a String because Strings are reference types. Why didn't the string change? What is going on?   I spent hours unssuccessfully researching this anomaly until finally, I had a Eureka moment: This code: String MyString = "AAA"; Is semantically equivalent to this code (note this code doesn't actually compile): String MyString = new String(); MyString = "AAA"; Key Point: In the function, the copy of the reference is pointed to a new object and THAT object is modified. The original reference and what it points to is unchanged. You can simulate this behavior by modifying the class example code to look like this:      void SetMyClass(MyClass myClass)  // call by 'value'    {        //myClass.StrTag = "BBB";        myClass = new MyClass();        myClass.StrTag = "BBB";    } Now when you call the SetMyClass function without using ref, the parameter is unchanged...just like the string example.  I hope someone finds this useful. Steve Wellens

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  • Strategies for managUse of types in Python

    - by dave
    I'm a long time programmer in C# but have been coding in Python for the past year. One of the big hurdles for me was the lack of type definitions for variables and parameters. Whereas I totally get the idea of duck typing, I do find it frustrating that I can't tell the type of a variable just by looking at it. This is an issue when you look at someone else's code where they've used ambiguous names for method parameters (see edit below). In a few cases, I've added asserts to ensure parameters comply with an expected type but this goes against the whole duck typing thing. On some methods, I'll document the expected type of parameters (eg: list of user objects), but even this seems to go against the idea of just using an object and let the runtime deal with exceptions. What strategies do you use to avoid typing problems in Python? Edit: Example of the parameter naming issues: If our code base we have a task object (ORM object) and a task_obj object (higher level object that embeds a task). Needless to say, many methods accept a parameter named 'task'. The method might expect a task or a task_obj or some other construct such as a dictionary of task properties - it is not clear. It is them up to be to look at how that parameter is used in order to work out what the method expects.

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  • Passing Parameters Between Web-Services and JSF Pages

    - by shay.shmeltzer
    This is another quick demo that shows a common scenario that combines several demos I did in the past. The scenario – we have two web services, one returns a list of objects, the other allows us to update an object. We want to build a page flow where the first page shows us the list of objects, allows us to select one, and then we can edit that instance in the next page and call the second web service to update our data source. The demo shows: How to select a row and save the object value in a pageFlowScope. (using setPropertyListener). How to create a page that allows me to modify the value of the pageFlowScope object, and how to pass the object as a parameter to the second Web service. Check it out here:

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  • A good way to build a game loop in OpenGL

    - by Jeff
    I'm currently beginning to learn OpenGL at school, and I've started making a simple game the other day (on my own, not for school). I'm using freeglut, and am building it in C, so for my game loop I had really just been using a function I made passed to glutIdleFunc to update all the drawing and physics in one pass. This was fine for simple animations that I didn't care too much about the frame rate, but since the game is mostly physics based, I really want to (need to) tie down how fast it's updating. So my first attempt was to have my function I pass to glutIdleFunc (myIdle()) to keep track of how much time has passed since the previous call to it, and update the physics (and currently graphics) every so many milliseconds. I used timeGetTime() to do this (by using <windows.h>). And this got me to thinking, is using the idle function really a good way of going about the game loop? My question is, what is a better way to implement the game loop in OpenGL? Should I avoid using the idle function?

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  • jrunscript as a cross platform scripting environment

    - by user12798506
    ?????????????????????????????????????????????????????????sh????????????UNIX???????????????????sh???????????????????????????????????????????Windows????????????????? sh??????????????find?grep?sed?awk???Windows??????????????????????????????????????????????????????????????????????????????????????????????Windows???Cygwin????????????sh??????Windows??????????????Cygwin????????????????????????????????????????????JDK?????jrunscript?????JavaScript???????????????????????1?????????jrunscript??????????????????? Windows???UNIX??????????????????????? find?grep?sed?awk?????????sh???????????????Windows Script Host??????? Java????????????? ??????????????????????????????????????????????????????????(?????????????????????????????????????????) ?????????????JDK 6??????????????????????????PC????????????????JDK 6?PC????????????????????????????????????JDK????????????????????????????????????????jrunscript?????????????????????????? ?????jrunscript????JavaScript?????????????????????????????????????????? 1) Windows???UNIX????????????????? ?????????????????????????????????????????JavaScript???mytool.js???????????????????????jrunscript???????????UNIX????sh???????Windows????bat????????????????????? mytool.sh (UNIX?): #!/bin/sh bindir=$(cd $(dirname $0) && pwd) case "`uname`" in CYGWIN*) bindir=`cygpath -w "$bindir"` ;; esac jrunscript "${bindir}/mytool.js" $* mytool.bat (Windows?): @echo off set bindir=%~dp0 jrunscript "%bindir%mytool.js" %* UNIX??sh????????Cygwin???????????????????????????????????????????js??????????????UNIX?Windows??????????????????????????????? 2) jrunscript??cat, cp, find?grep?????? jrunscript???UNIX?????????????????????????????????? jrunscript JavaScript built-in functions ????UNIX??sh?????????????????????UNIX?????????????????????????????????????????src??????????java????????????enum???????java?????????????????????????????????????????????? find('src', '.*.java', function(f) { grep('enum', f); }); ???????UNIX?????????????????????????????????????????????????????????????????????????????????????????cp(from, to)??????????????????????????????????????????UNIX??????????? $ cp -r src/* tmp/ ?????????????????????????????????????????find()???????cp -r????????·?????????????????????? function cpr(fromdir, todir, pattern) { if (pattern == undefined) { pattern = ".*"; } var frdir = pathToFile(fromdir).getCanonicalPath(); find(fromdir, pattern, function(f) { // relative dir of file f from 'fromdir'. var relative = f.getParentFile().getCanonicalPath().substring(frdir.length() + 1); var dstdir = pathToFile(todir + "/" + relative); if (!dstdir.exists()) { // Create the destination dir for file f. mkdirs(dstdir); } // Copy file f to 'dstdir'. cp(f, dstdir + "/" + f.getName()); }); } java?????I/O?API??Windows?????????????"/"??????????????????????????????UNIX?Windows?????????????? ????????????exec(cmd)?????????jar???????????????????????????????????????????? $ jrunscript js> exec("jar xvf example.jar") META-INF/ ?????????????µ???B META-INF/MANIFEST.MF ???W?J???????µ???B com/ ?????????????µ???B com/example/ ?????????????µ???B com/example/Bar.class ???W?J???????µ???B com/example/dummy/ ?????????????µ???B com/example/dummy/dummy.txt ?????o???????µ???B com/example/dummy.properties ?????o???????µ???B com/example/Foo.class ???W?J???????µ???B ???exec()?????????????????????????????????????????????????????????????????Windows????????????I/O??????????????????????????????????BAT????????? errmsg.bat: for /L %%i in (1,1,50) do echo "Error Message count = %%i" 1&2 jrunscript??exec()???????????????18??????????????????????????????????? C:\tmp>jrunscript -e "exec('errmsg.bat')" C:\tmp>for /L %i in (1 1 100) do echo "Error Message count = %i" 1>&2 C:\tmp>echo "Error Message count = 1" 1>&2 : C:\tmp>echo "Error Message count = 18" 1>&2 ? ??? ???????????exec()?????????????????????????????????????????????????????????????????DataInputStream???????????????????????? $ jrunscript js this["exec"].toString() function exec(cmd) { var process = java.lang.Runtime.getRuntime().exec(cmd); var inp = new DataInputStream(process.getInputStream()); var line = null; while ((line = inp.readLine()) != null) { println(line); } process.waitFor(); $exit = process.exitValue(); } ?????????????????????????????????????????????????????exec()???????????????exec()?????????????????????????????exec()??????? function exec(cmd) { var process = java.lang.Runtime.getRuntime().exec(cmd); var stdworker = new java.lang.Runnable( {run: function() { cat(process.getInputStream()); }}); var errworker = new java.lang.Runnable( {run: function() { cat(process.getErrorStream()); }}); new java.lang.Thread(stdworker).start(); new java.lang.Thread(errworker).start(); return proc.waitFor(); } ???????????????????cat()???????????cat()?InputStreamReader?????????????????????????????????????????????????? 3) JavaScript???????????????? JavaScript?Java???????????????????????JavaScript????????????Ruby?Groovy?Scala???????????????????????????????????????????????10MB?????????????????????????????????????JavaScript????????????????????KB?????????????MB?JAR??????????????????????????JRE?JDK?????????????????????????????????????????

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  • Difference between IN and FIND_IN_SET

    - by Madhan ayyasamy
    Hi Friends,You may be confused with IN() and FIND_IN_SET() MYSQL functions. There are specific case/situation for both functions where to use which Mysql function. Look at below explanation about IN() and FIND_IN_SET()IN() : This function is used when you have a list of possible values and a single value in your database.Example: WHERE memberid IN (1,2,3)FIND_IN_SET() : This function is used where you have comma separated list of values stored in database and want to see if a certain value exists in that comma seperated list.Example: WHERE FIND_IN_SET( ‘table column name like id’, 'dynamic idlist' )

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  • JSCompress fails to compress my js file - why?

    - by Renso
    Issue: You use the online compression utility jscompress.com to compress your js file but it fails with an error. Why this may be happening and how to fix it. Possible causes: Apparently not using open and closing curly brackets in an IF statement would cause this. Well turns out this is not the case. Look at the following example and see if you can figure out what the issue is :-)   function SetupDeliveredVPRecontactNotes($item, id) {     var theData;     $.ajax({         data: { deliveredVPId: id },         url: $('#ajaxGetDeliveredVPRecontactNotesUrl').val(),         type: "GET",         async: false,         dataType: "html",         success: function(data, result) {             $item.empty();             var input = '<textarea class="recontactNote" rows="4" name="DeliveredVPRecontactNotes_' + id + '" id="DeliveredVPRecontactNotes_' + id + '" cols="115">' + data + '</textarea>';             $item.append(input);             theData = data;         },         error: function(XMLHttpRequest, textStatus, errorThrown) {             $item.empty();             alert("An error occurred: The operation to retrieve the DeliveredVP's Recontact Notes has failed");         }     });                  //ajax     return theData; }     Solution: The name of the method/function is the same as the message in the ALERT message when the spaces are removed: " DeliveredVP Recontact Notes" becomes " DeliveredVPRecontactNotes" and mathes that of the function. So I changed it to " DeliveredVP's Recontact Notes"

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  • Using R to Analyze G1GC Log Files

    - by user12620111
    Using R to Analyze G1GC Log Files body, td { font-family: sans-serif; background-color: white; font-size: 12px; margin: 8px; } tt, code, pre { font-family: 'DejaVu Sans Mono', 'Droid Sans Mono', 'Lucida Console', Consolas, Monaco, monospace; } h1 { font-size:2.2em; } h2 { font-size:1.8em; } h3 { font-size:1.4em; } h4 { font-size:1.0em; } h5 { font-size:0.9em; } h6 { font-size:0.8em; } a:visited { color: rgb(50%, 0%, 50%); } pre { margin-top: 0; max-width: 95%; border: 1px solid #ccc; white-space: pre-wrap; } pre code { display: block; padding: 0.5em; } code.r, code.cpp { background-color: #F8F8F8; } table, td, th { border: none; } blockquote { color:#666666; margin:0; padding-left: 1em; border-left: 0.5em #EEE solid; } hr { height: 0px; border-bottom: none; border-top-width: thin; border-top-style: dotted; border-top-color: #999999; } @media print { * { background: transparent !important; color: black !important; filter:none !important; -ms-filter: none !important; } body { 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  Using R to Analyze G1GC Log Files   Using R to Analyze G1GC Log Files Introduction Working in Oracle Platform Integration gives an engineer opportunities to work on a wide array of technologies. My team’s goal is to make Oracle applications run best on the Solaris/SPARC platform. When looking for bottlenecks in a modern applications, one needs to be aware of not only how the CPUs and operating system are executing, but also network, storage, and in some cases, the Java Virtual Machine. I was recently presented with about 1.5 GB of Java Garbage First Garbage Collector log file data. If you’re not familiar with the subject, you might want to review Garbage First Garbage Collector Tuning by Monica Beckwith. The customer had been running Java HotSpot 1.6.0_31 to host a web application server. I was told that the Solaris/SPARC server was running a Java process launched using a commmand line that included the following flags: -d64 -Xms9g -Xmx9g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:InitiatingHeapOccupancyPercent=80 -XX:PermSize=256m -XX:MaxPermSize=256m -XX:+PrintGC -XX:+PrintGCTimeStamps -XX:+PrintHeapAtGC -XX:+PrintGCDateStamps -XX:+PrintFlagsFinal -XX:+DisableExplicitGC -XX:+UnlockExperimentalVMOptions -XX:ParallelGCThreads=8 Several sources on the internet indicate that if I were to print out the 1.5 GB of log files, it would require enough paper to fill the bed of a pick up truck. Of course, it would be fruitless to try to scan the log files by hand. Tools will be required to summarize the contents of the log files. Others have encountered large Java garbage collection log files. There are existing tools to analyze the log files: IBM’s GC toolkit The chewiebug GCViewer gchisto HPjmeter Instead of using one of the other tools listed, I decide to parse the log files with standard Unix tools, and analyze the data with R. Data Cleansing The log files arrived in two different formats. I guess that the difference is that one set of log files was generated using a more verbose option, maybe -XX:+PrintHeapAtGC, and the other set of log files was generated without that option. Format 1 In some of the log files, the log files with the less verbose format, a single trace, i.e. the report of a singe garbage collection event, looks like this: {Heap before GC invocations=12280 (full 61): garbage-first heap total 9437184K, used 7499918K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) region size 4096K, 1 young (4096K), 0 survivors (0K) compacting perm gen total 262144K, used 144077K [0xffffffff40000000, 0xffffffff50000000, 0xffffffff50000000) the space 262144K, 54% used [0xffffffff40000000, 0xffffffff48cb3758, 0xffffffff48cb3800, 0xffffffff50000000) No shared spaces configured. 2014-05-14T07:24:00.988-0700: 60586.353: [GC pause (young) 7324M->7320M(9216M), 0.1567265 secs] Heap after GC invocations=12281 (full 61): garbage-first heap total 9437184K, used 7496533K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) region size 4096K, 0 young (0K), 0 survivors (0K) compacting perm gen total 262144K, used 144077K [0xffffffff40000000, 0xffffffff50000000, 0xffffffff50000000) the space 262144K, 54% used [0xffffffff40000000, 0xffffffff48cb3758, 0xffffffff48cb3800, 0xffffffff50000000) No shared spaces configured. } A simple grep can be used to extract a summary: $ grep "\[ GC pause (young" g1gc.log 2014-05-13T13:24:35.091-0700: 3.109: [GC pause (young) 20M->5029K(9216M), 0.0146328 secs] 2014-05-13T13:24:35.440-0700: 3.459: [GC pause (young) 9125K->6077K(9216M), 0.0086723 secs] 2014-05-13T13:24:37.581-0700: 5.599: [GC pause (young) 25M->8470K(9216M), 0.0203820 secs] 2014-05-13T13:24:42.686-0700: 10.704: [GC pause (young) 44M->15M(9216M), 0.0288848 secs] 2014-05-13T13:24:48.941-0700: 16.958: [GC pause (young) 51M->20M(9216M), 0.0491244 secs] 2014-05-13T13:24:56.049-0700: 24.066: [GC pause (young) 92M->26M(9216M), 0.0525368 secs] 2014-05-13T13:25:34.368-0700: 62.383: [GC pause (young) 602M->68M(9216M), 0.1721173 secs] But that format wasn't easily read into R, so I needed to be a bit more tricky. I used the following Unix command to create a summary file that was easy for R to read. $ echo "SecondsSinceLaunch BeforeSize AfterSize TotalSize RealTime" $ grep "\[GC pause (young" g1gc.log | grep -v mark | sed -e 's/[A-SU-z\(\),]/ /g' -e 's/->/ /' -e 's/: / /g' | more SecondsSinceLaunch BeforeSize AfterSize TotalSize RealTime 2014-05-13T13:24:35.091-0700 3.109 20 5029 9216 0.0146328 2014-05-13T13:24:35.440-0700 3.459 9125 6077 9216 0.0086723 2014-05-13T13:24:37.581-0700 5.599 25 8470 9216 0.0203820 2014-05-13T13:24:42.686-0700 10.704 44 15 9216 0.0288848 2014-05-13T13:24:48.941-0700 16.958 51 20 9216 0.0491244 2014-05-13T13:24:56.049-0700 24.066 92 26 9216 0.0525368 2014-05-13T13:25:34.368-0700 62.383 602 68 9216 0.1721173 Format 2 In some of the log files, the log files with the more verbose format, a single trace, i.e. the report of a singe garbage collection event, was more complicated than Format 1. Here is a text file with an example of a single G1GC trace in the second format. As you can see, it is quite complicated. It is nice that there is so much information available, but the level of detail can be overwhelming. I wrote this awk script (download) to summarize each trace on a single line. #!/usr/bin/env awk -f BEGIN { printf("SecondsSinceLaunch IncrementalCount FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize\n") } ###################### # Save count data from lines that are at the start of each G1GC trace. # Each trace starts out like this: # {Heap before GC invocations=14 (full 0): # garbage-first heap total 9437184K, used 325496K [0xfffffffd00000000, 0xffffffff40000000, 0xffffffff40000000) ###################### /{Heap.*full/{ gsub ( "\\)" , "" ); nf=split($0,a,"="); split(a[2],b," "); getline; if ( match($0, "first") ) { G1GC=1; IncrementalCount=b[1]; FullCount=substr( b[3], 1, length(b[3])-1 ); } else { G1GC=0; } } ###################### # Pull out time stamps that are in lines with this format: # 2014-05-12T14:02:06.025-0700: 94.312: [GC pause (young), 0.08870154 secs] ###################### /GC pause/ { DateTime=$1; SecondsSinceLaunch=substr($2, 1, length($2)-1); } ###################### # Heap sizes are in lines that look like this: # [ 4842M->4838M(9216M)] ###################### /\[ .*]$/ { gsub ( "\\[" , "" ); gsub ( "\ \]" , "" ); gsub ( "->" , " " ); gsub ( "\\( " , " " ); gsub ( "\ \)" , " " ); split($0,a," "); if ( split(a[1],b,"M") > 1 ) {BeforeSize=b[1]*1024;} if ( split(a[1],b,"K") > 1 ) {BeforeSize=b[1];} if ( split(a[2],b,"M") > 1 ) {AfterSize=b[1]*1024;} if ( split(a[2],b,"K") > 1 ) {AfterSize=b[1];} if ( split(a[3],b,"M") > 1 ) {TotalSize=b[1]*1024;} if ( split(a[3],b,"K") > 1 ) {TotalSize=b[1];} } ###################### # Emit an output line when you find input that looks like this: # [Times: user=1.41 sys=0.08, real=0.24 secs] ###################### /\[Times/ { if (G1GC==1) { gsub ( "," , "" ); split($2,a,"="); UserTime=a[2]; split($3,a,"="); SysTime=a[2]; split($4,a,"="); RealTime=a[2]; print DateTime,SecondsSinceLaunch,IncrementalCount,FullCount,UserTime,SysTime,RealTime,BeforeSize,AfterSize,TotalSize; G1GC=0; } } The resulting summary is about 25X smaller that the original file, but still difficult for a human to digest. SecondsSinceLaunch IncrementalCount FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ... 2014-05-12T18:36:34.669-0700: 3985.744 561 0 0.57 0.06 0.16 1724416 1720320 9437184 2014-05-12T18:36:34.839-0700: 3985.914 562 0 0.51 0.06 0.19 1724416 1720320 9437184 2014-05-12T18:36:35.069-0700: 3986.144 563 0 0.60 0.04 0.27 1724416 1721344 9437184 2014-05-12T18:36:35.354-0700: 3986.429 564 0 0.33 0.04 0.09 1725440 1722368 9437184 2014-05-12T18:36:35.545-0700: 3986.620 565 0 0.58 0.04 0.17 1726464 1722368 9437184 2014-05-12T18:36:35.726-0700: 3986.801 566 0 0.43 0.05 0.12 1726464 1722368 9437184 2014-05-12T18:36:35.856-0700: 3986.930 567 0 0.30 0.04 0.07 1726464 1723392 9437184 2014-05-12T18:36:35.947-0700: 3987.023 568 0 0.61 0.04 0.26 1727488 1723392 9437184 2014-05-12T18:36:36.228-0700: 3987.302 569 0 0.46 0.04 0.16 1731584 1724416 9437184 Reading the Data into R Once the GC log data had been cleansed, either by processing the first format with the shell script, or by processing the second format with the awk script, it was easy to read the data into R. g1gc.df = read.csv("summary.txt", row.names = NULL, stringsAsFactors=FALSE,sep="") str(g1gc.df) ## 'data.frame': 8307 obs. of 10 variables: ## $ row.names : chr "2014-05-12T14:00:32.868-0700:" "2014-05-12T14:00:33.179-0700:" "2014-05-12T14:00:33.677-0700:" "2014-05-12T14:00:35.538-0700:" ... ## $ SecondsSinceLaunch: num 1.16 1.47 1.97 3.83 6.1 ... ## $ IncrementalCount : int 0 1 2 3 4 5 6 7 8 9 ... ## $ FullCount : int 0 0 0 0 0 0 0 0 0 0 ... ## $ UserTime : num 0.11 0.05 0.04 0.21 0.08 0.26 0.31 0.33 0.34 0.56 ... ## $ SysTime : num 0.04 0.01 0.01 0.05 0.01 0.06 0.07 0.06 0.07 0.09 ... ## $ RealTime : num 0.02 0.02 0.01 0.04 0.02 0.04 0.05 0.04 0.04 0.06 ... ## $ BeforeSize : int 8192 5496 5768 22528 24576 43008 34816 53248 55296 93184 ... ## $ AfterSize : int 1400 1672 2557 4907 7072 14336 16384 18432 19456 21504 ... ## $ TotalSize : int 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 9437184 ... head(g1gc.df) ## row.names SecondsSinceLaunch IncrementalCount ## 1 2014-05-12T14:00:32.868-0700: 1.161 0 ## 2 2014-05-12T14:00:33.179-0700: 1.472 1 ## 3 2014-05-12T14:00:33.677-0700: 1.969 2 ## 4 2014-05-12T14:00:35.538-0700: 3.830 3 ## 5 2014-05-12T14:00:37.811-0700: 6.103 4 ## 6 2014-05-12T14:00:41.428-0700: 9.720 5 ## FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ## 1 0 0.11 0.04 0.02 8192 1400 9437184 ## 2 0 0.05 0.01 0.02 5496 1672 9437184 ## 3 0 0.04 0.01 0.01 5768 2557 9437184 ## 4 0 0.21 0.05 0.04 22528 4907 9437184 ## 5 0 0.08 0.01 0.02 24576 7072 9437184 ## 6 0 0.26 0.06 0.04 43008 14336 9437184 Basic Statistics Once the data has been read into R, simple statistics are very easy to generate. All of the numbers from high school statistics are available via simple commands. For example, generate a summary of every column: summary(g1gc.df) ## row.names SecondsSinceLaunch IncrementalCount FullCount ## Length:8307 Min. : 1 Min. : 0 Min. : 0.0 ## Class :character 1st Qu.: 9977 1st Qu.:2048 1st Qu.: 0.0 ## Mode :character Median :12855 Median :4136 Median : 12.0 ## Mean :12527 Mean :4156 Mean : 31.6 ## 3rd Qu.:15758 3rd Qu.:6262 3rd Qu.: 61.0 ## Max. :55484 Max. :8391 Max. :113.0 ## UserTime SysTime RealTime BeforeSize ## Min. :0.040 Min. :0.0000 Min. : 0.0 Min. : 5476 ## 1st Qu.:0.470 1st Qu.:0.0300 1st Qu.: 0.1 1st Qu.:5137920 ## Median :0.620 Median :0.0300 Median : 0.1 Median :6574080 ## Mean :0.751 Mean :0.0355 Mean : 0.3 Mean :5841855 ## 3rd Qu.:0.920 3rd Qu.:0.0400 3rd Qu.: 0.2 3rd Qu.:7084032 ## Max. :3.370 Max. :1.5600 Max. :488.1 Max. :8696832 ## AfterSize TotalSize ## Min. : 1380 Min. :9437184 ## 1st Qu.:5002752 1st Qu.:9437184 ## Median :6559744 Median :9437184 ## Mean :5785454 Mean :9437184 ## 3rd Qu.:7054336 3rd Qu.:9437184 ## Max. :8482816 Max. :9437184 Q: What is the total amount of User CPU time spent in garbage collection? sum(g1gc.df$UserTime) ## [1] 6236 As you can see, less than two hours of CPU time was spent in garbage collection. Is that too much? To find the percentage of time spent in garbage collection, divide the number above by total_elapsed_time*CPU_count. In this case, there are a lot of CPU’s and it turns out the the overall amount of CPU time spent in garbage collection isn’t a problem when viewed in isolation. When calculating rates, i.e. events per unit time, you need to ask yourself if the rate is homogenous across the time period in the log file. Does the log file include spikes of high activity that should be separately analyzed? Averaging in data from nights and weekends with data from business hours may alias problems. If you have a reason to suspect that the garbage collection rates include peaks and valleys that need independent analysis, see the “Time Series” section, below. Q: How much garbage is collected on each pass? The amount of heap space that is recovered per GC pass is surprisingly low: At least one collection didn’t recover any data. (“Min.=0”) 25% of the passes recovered 3MB or less. (“1st Qu.=3072”) Half of the GC passes recovered 4MB or less. (“Median=4096”) The average amount recovered was 56MB. (“Mean=56390”) 75% of the passes recovered 36MB or less. (“3rd Qu.=36860”) At least one pass recovered 2GB. (“Max.=2121000”) g1gc.df$Delta = g1gc.df$BeforeSize - g1gc.df$AfterSize summary(g1gc.df$Delta) ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 0 3070 4100 56400 36900 2120000 Q: What is the maximum User CPU time for a single collection? The worst garbage collection (“Max.”) is many standard deviations away from the mean. The data appears to be right skewed. summary(g1gc.df$UserTime) ## Min. 1st Qu. Median Mean 3rd Qu. Max. ## 0.040 0.470 0.620 0.751 0.920 3.370 sd(g1gc.df$UserTime) ## [1] 0.3966 Basic Graphics Once the data is in R, it is trivial to plot the data with formats including dot plots, line charts, bar charts (simple, stacked, grouped), pie charts, boxplots, scatter plots histograms, and kernel density plots. Histogram of User CPU Time per Collection I don't think that this graph requires any explanation. hist(g1gc.df$UserTime, main="User CPU Time per Collection", xlab="Seconds", ylab="Frequency") Box plot to identify outliers When the initial data is viewed with a box plot, you can see the one crazy outlier in the real time per GC. Save this data point for future analysis and drop the outlier so that it’s not throwing off our statistics. Now the box plot shows many outliers, which will be examined later, using times series analysis. Notice that the scale of the x-axis changes drastically once the crazy outlier is removed. par(mfrow=c(2,1)) boxplot(g1gc.df$UserTime,g1gc.df$SysTime,g1gc.df$RealTime, main="Box Plot of Time per GC\n(dominated by a crazy outlier)", names=c("usr","sys","elapsed"), xlab="Seconds per GC", ylab="Time (Seconds)", horizontal = TRUE, outcol="red") crazy.outlier.df=g1gc.df[g1gc.df$RealTime > 400,] g1gc.df=g1gc.df[g1gc.df$RealTime < 400,] boxplot(g1gc.df$UserTime,g1gc.df$SysTime,g1gc.df$RealTime, main="Box Plot of Time per GC\n(crazy outlier excluded)", names=c("usr","sys","elapsed"), xlab="Seconds per GC", ylab="Time (Seconds)", horizontal = TRUE, outcol="red") box(which = "outer", lty = "solid") Here is the crazy outlier for future analysis: crazy.outlier.df ## row.names SecondsSinceLaunch IncrementalCount ## 8233 2014-05-12T23:15:43.903-0700: 20741 8316 ## FullCount UserTime SysTime RealTime BeforeSize AfterSize TotalSize ## 8233 112 0.55 0.42 488.1 8381440 8235008 9437184 ## Delta ## 8233 146432 R Time Series Data To analyze the garbage collection as a time series, I’ll use Z’s Ordered Observations (zoo). “zoo is the creator for an S3 class of indexed totally ordered observations which includes irregular time series.” require(zoo) ## Loading required package: zoo ## ## Attaching package: 'zoo' ## ## The following objects are masked from 'package:base': ## ## as.Date, as.Date.numeric head(g1gc.df[,1]) ## [1] "2014-05-12T14:00:32.868-0700:" "2014-05-12T14:00:33.179-0700:" ## [3] "2014-05-12T14:00:33.677-0700:" "2014-05-12T14:00:35.538-0700:" ## [5] "2014-05-12T14:00:37.811-0700:" "2014-05-12T14:00:41.428-0700:" options("digits.secs"=3) times=as.POSIXct( g1gc.df[,1], format="%Y-%m-%dT%H:%M:%OS%z:") g1gc.z = zoo(g1gc.df[,-c(1)], order.by=times) head(g1gc.z) ## SecondsSinceLaunch IncrementalCount FullCount ## 2014-05-12 17:00:32.868 1.161 0 0 ## 2014-05-12 17:00:33.178 1.472 1 0 ## 2014-05-12 17:00:33.677 1.969 2 0 ## 2014-05-12 17:00:35.538 3.830 3 0 ## 2014-05-12 17:00:37.811 6.103 4 0 ## 2014-05-12 17:00:41.427 9.720 5 0 ## UserTime SysTime RealTime BeforeSize AfterSize ## 2014-05-12 17:00:32.868 0.11 0.04 0.02 8192 1400 ## 2014-05-12 17:00:33.178 0.05 0.01 0.02 5496 1672 ## 2014-05-12 17:00:33.677 0.04 0.01 0.01 5768 2557 ## 2014-05-12 17:00:35.538 0.21 0.05 0.04 22528 4907 ## 2014-05-12 17:00:37.811 0.08 0.01 0.02 24576 7072 ## 2014-05-12 17:00:41.427 0.26 0.06 0.04 43008 14336 ## TotalSize Delta ## 2014-05-12 17:00:32.868 9437184 6792 ## 2014-05-12 17:00:33.178 9437184 3824 ## 2014-05-12 17:00:33.677 9437184 3211 ## 2014-05-12 17:00:35.538 9437184 17621 ## 2014-05-12 17:00:37.811 9437184 17504 ## 2014-05-12 17:00:41.427 9437184 28672 Example of Two Benchmark Runs in One Log File The data in the following graph is from a different log file, not the one of primary interest to this article. I’m including this image because it is an example of idle periods followed by busy periods. It would be uninteresting to average the rate of garbage collection over the entire log file period. More interesting would be the rate of garbage collect in the two busy periods. Are they the same or different? Your production data may be similar, for example, bursts when employees return from lunch and idle times on weekend evenings, etc. Once the data is in an R Time Series, you can analyze isolated time windows. Clipping the Time Series data Flashing back to our test case… Viewing the data as a time series is interesting. You can see that the work intensive time period is between 9:00 PM and 3:00 AM. Lets clip the data to the interesting period:     par(mfrow=c(2,1)) plot(g1gc.z$UserTime, type="h", main="User Time per GC\nTime: Complete Log File", xlab="Time of Day", ylab="CPU Seconds per GC", col="#1b9e77") clipped.g1gc.z=window(g1gc.z, start=as.POSIXct("2014-05-12 21:00:00"), end=as.POSIXct("2014-05-13 03:00:00")) plot(clipped.g1gc.z$UserTime, type="h", main="User Time per GC\nTime: Limited to Benchmark Execution", xlab="Time of Day", ylab="CPU Seconds per GC", col="#1b9e77") box(which = "outer", lty = "solid") Cumulative Incremental and Full GC count Here is the cumulative incremental and full GC count. When the line is very steep, it indicates that the GCs are repeating very quickly. Notice that the scale on the Y axis is different for full vs. incremental. plot(clipped.g1gc.z[,c(2:3)], main="Cumulative Incremental and Full GC count", xlab="Time of Day", col="#1b9e77") GC Analysis of Benchmark Execution using Time Series data In the following series of 3 graphs: The “After Size” show the amount of heap space in use after each garbage collection. Many Java objects are still referenced, i.e. alive, during each garbage collection. This may indicate that the application has a memory leak, or may indicate that the application has a very large memory footprint. Typically, an application's memory footprint plateau's in the early stage of execution. One would expect this graph to have a flat top. The steep decline in the heap space may indicate that the application crashed after 2:00. The second graph shows that the outliers in real execution time, discussed above, occur near 2:00. when the Java heap seems to be quite full. The third graph shows that Full GCs are infrequent during the first few hours of execution. The rate of Full GC's, (the slope of the cummulative Full GC line), changes near midnight.   plot(clipped.g1gc.z[,c("AfterSize","RealTime","FullCount")], xlab="Time of Day", col=c("#1b9e77","red","#1b9e77")) GC Analysis of heap recovered Each GC trace includes the amount of heap space in use before and after the individual GC event. During garbage coolection, unreferenced objects are identified, the space holding the unreferenced objects is freed, and thus, the difference in before and after usage indicates how much space has been freed. The following box plot and bar chart both demonstrate the same point - the amount of heap space freed per garbage colloection is surprisingly low. par(mfrow=c(2,1)) boxplot(as.vector(clipped.g1gc.z$Delta), main="Amount of Heap Recovered per GC Pass", xlab="Size in KB", horizontal = TRUE, col="red") hist(as.vector(clipped.g1gc.z$Delta), main="Amount of Heap Recovered per GC Pass", xlab="Size in KB", breaks=100, col="red") box(which = "outer", lty = "solid") This graph is the most interesting. The dark blue area shows how much heap is occupied by referenced Java objects. This represents memory that holds live data. The red fringe at the top shows how much data was recovered after each garbage collection. barplot(clipped.g1gc.z[,c("AfterSize","Delta")], col=c("#7570b3","#e7298a"), xlab="Time of Day", border=NA) legend("topleft", c("Live Objects","Heap Recovered on GC"), fill=c("#7570b3","#e7298a")) box(which = "outer", lty = "solid") When I discuss the data in the log files with the customer, I will ask for an explaination for the large amount of referenced data resident in the Java heap. There are two are posibilities: There is a memory leak and the amount of space required to hold referenced objects will continue to grow, limited only by the maximum heap size. After the maximum heap size is reached, the JVM will throw an “Out of Memory” exception every time that the application tries to allocate a new object. If this is the case, the aplication needs to be debugged to identify why old objects are referenced when they are no longer needed. The application has a legitimate requirement to keep a large amount of data in memory. The customer may want to further increase the maximum heap size. Another possible solution would be to partition the application across multiple cluster nodes, where each node has responsibility for managing a unique subset of the data. Conclusion In conclusion, R is a very powerful tool for the analysis of Java garbage collection log files. The primary difficulty is data cleansing so that information can be read into an R data frame. Once the data has been read into R, a rich set of tools may be used for thorough evaluation.

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  • Was API hooking done as needed for Stuxnet to work? I don't think so

    - by The Kaykay
    Caveat: I am a political science student and I have tried my level best to understand the technicalities; if I still sound naive please overlook that. In the Symantec report on Stuxnet, the authors say that once the worm infects the 32-bit Windows computer which has a WINCC setup on it, Stuxnet does many things and that it specifically hooks the function CreateFileA(). This function is the route which the worm uses to actually infect the .s7p project files that are used to program the PLCs. ie when the PLC programmer opens a file with .s7p the control transfers to the hooked function CreateFileA_hook() instead of CreateFileA(). Once Stuxnet gains the control it covertly inserts code blocks into the PLC without the programmers knowledge and hides it from his view. However, it should be noted that there is also one more function called CreateFileW() which does the same task as CreateFileA() but both work on different character sets. CreateFileA works with ASCII character set and CreateFileW works with wide characters or Unicode character set. Farsi (the language of the Iranians) is a language that needs unicode character set and not ASCII Characters. I'm assuming that the developers of any famous commercial software (for ex. WinCC) that will be sold in many countries will take 'Localization' and/or 'Internationalization' into consideration while it is being developed in order to make the product fail-safe ie. the software developers would use UNICODE while compiling their code and not just 'ASCII'. Thus, I think that CreateFileW() would have been invoked on a WINCC system in Iran instead of CreateFileA(). Do you agree? My question is: If Stuxnet has hooked only the function CreateFileA() then based on the above assumption there is a significant chance that it did not work at all? I think my doubt will get clarified if: my assumption is proved wrong, or the Symantec report is proved incorrect. Please help me clarify this doubt. Note: I had posted this question on the general stackexchange website and did not get appropriate responses that I was looking for so I'm posting it here.

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  • Area of testing

    - by ?????? ??????????
    I'm trying to understand which part of my code I should to test. I have some code. Below is example of this code, just to understand the idea. Depends of some parametrs I put one or another currency to "Event" and return his serialization in the controller. Which part of code I should to test? Just the final serialization, or only "Event" or every method: getJson, getRows, fillCurrency, setCurrency? class Controller { public function getJson() { $rows = $eventManager->getRows(); return new JsonResponse($rows); } } class EventManager { public function getRows() { //some code here if ($parameter == true) { $this->fillCurrency($event, $currency); } } public function fillCurrency($event, $currency) { //some code here if ($parameters == true) { $event->setCurrency($currency); } } } class Event { public function setCurrency($currency) { $this->updatedAt = new Datetime(); $this->currency = $currency; } }

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  • DDD and validation of aggregate root

    - by Mik378
    Suppose an aggregate root : MailConfiguration (wrapping an AddressPart object). The AddressPart object is a simple immutable value object with some fields like senderAdress, recipentAddress (to make example simple). As being an invariant object, AddressPart should logically wrap its own Validator (by the way of external a kind of AddressValidator for respecting Single Responsibility Principle) I read some articles that claimed an aggregateRoot must validate its 'children'. However, if we follow this principle, one could create an AddressPart with an uncohesive/invalid state. What are your opinion? Should I move the collaborator AddressValidator(used in constructor so in order to validate immediately the cohesion of an AddressPart) from AddressPart and assign it to aggregateRoot (MailConfiguration) ?

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  • What is wrong with my game loop/mechanic?

    - by elias94xx
    I'm currently working on a 2d sidescrolling game prototype in HTML5 canvas. My implementations so far include a sprite, vector, loop and ticker class/object. Which can be viewed here: http://elias-schuett.de/apps/_experiments/2d_ssg/js/ So my game essentially works well on todays lowspec PC's and laptops. But it does not on an older win xp machine I own and on my Android 2.3 device. I tend to get ~10 FPS with these devices which results in a too high delta value, which than automaticly gets fixed to 1.0 which results in a slow loop. Now I know for a fact that there is a way to implement a super smooth 60 or 30 FPS loop on both devices. Best example would be: http://playbiolab.com/ I don't need all the chunk and debugging technology impact.js offers. I could even write a super simple game where you just control a damn square and it still wouldn't run on a equally fast 30 or 60 fps. Here is the Loop class/object I'm using. It requires a requestAnimationFrame unify function. Both devices I've tested my game on support requestAnimationFrame, so there is no interval fallback. var Loop = function(callback) { this.fps = null; this.delta = 1; this.lastTime = +new Date; this.callback = callback; this.request = null; }; Loop.prototype.start = function() { var _this = this; this.request = requestAnimationFrame(function(now) { _this.start(); _this.delta = (now - _this.lastTime); _this.fps = 1000/_this.delta; _this.delta = _this.delta / (1000/60) > 2 ? 1 : _this.delta / (1000/60); _this.lastTime = now; _this.callback(); }); }; Loop.prototype.stop = function() { cancelAnimationFrame(this.request); };

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  • Simple alternating text in Visual Basic 2008

    - by Josh Grate
    I have a simple completed program, but i would like to add one more feature to it but I'm not sure how. I have it set up to send a message automatically every 7 seconds when a text field is selected, repeating the message of course. What I would like for it to do is alternate between two separate messages, instead just repeating the one. I would like the new program to post at an interval of 12 seconds. Can you help me? Here is my coding. Public Class Form1 Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick SendKeys.Send(TextBox1.Text) SendKeys.Send("{ENTER}") End Sub Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Timer1.Enabled = True Timer1.Interval = (TextBox2.Text) End Sub Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Timer1.Enabled = False End Sub Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load Timer1.Enabled = False End Sub End Class

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  • A Reusable Builder Class for .NET testing

    - by Liam McLennan
    When writing tests, other than end-to-end integration tests, we often need to construct test data objects. Of course this can be done using the class’s constructor and manually configuring the object, but to get many objects into a valid state soon becomes a large percentage of the testing effort. After many years of painstakingly creating builders for each of my domain objects I have finally become lazy enough to bother to write a generic, reusable builder class for .NET. To use it you instantiate a instance of the builder and configuring it with a builder method for each class you wish it to be able to build. The builder method should require no parameters and should return a new instance of the type in a default, valid state. In other words the builder method should be a Func<TypeToBeBuilt>. The best way to make this clear is with an example. In my application I have the following domain classes that I want to be able to use in my tests: public class Person { public string Name { get; set; } public int Age { get; set; } public bool IsAndroid { get; set; } } public class Building { public string Street { get; set; } public Person Manager { get; set; } } The builder for this domain is created like so: build = new Builder(); build.Configure(new Dictionary<Type, Func<object>> { {typeof(Building), () => new Building {Street = "Queen St", Manager = build.A<Person>()}}, {typeof(Person), () => new Person {Name = "Eugene", Age = 21}} }); Note how Building depends on Person, even though the person builder method is not defined yet. Now in a test I can retrieve a valid object from the builder: var person = build.A<Person>(); If I need a class in a customised state I can supply an Action<TypeToBeBuilt> to mutate the object post construction: var person = build.A<Person>(p => p.Age = 99); The power and efficiency of this approach becomes apparent when your tests require larger and more complex objects than Person and Building. When I get some time I intend to implement the same functionality in Javascript and Ruby. Here is the full source of the Builder class: public class Builder { private Dictionary<Type, Func<object>> defaults; public void Configure(Dictionary<Type, Func<object>> defaults) { this.defaults = defaults; } public T A<T>() { if (!defaults.ContainsKey(typeof(T))) throw new ArgumentException("No object of type " + typeof(T).Name + " has been configured with the builder."); T o = (T)defaults[typeof(T)](); return o; } public T A<T>(Action<T> customisation) { T o = A<T>(); customisation(o); return o; } }

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  • In ADUC MMC, Advanced View, how to get Attribute Editor tab on the result of a Find?

    - by geoffc
    In Win2008 MS added a new Tab on objects in ADUC. Called Attribute Editor it is like Novell Console One's Other tab, or an arbitrary LDAP editor view, or an ADSI Edit style view. Basically it shows all allowed attributes for the object class, and allows you to edit according to your permissions. You need to enable Advanced Options in the View menu before it shows up. This is great, however it only shows up when you browse the directory tree and select an object. If you use the Find tool and open an object Attribute Editor is not shown. How annoying! Especially if your domain has more than 2000 users in a single container, then you almost must use Find to get to an object. Is there any way to make the Attribute Editor tab show up after using Find to open an object?

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  • What is a good strategy for binding view objects to model objects in C++?

    - by B.J.
    Imagine I have a rich data model that is represented by a hierarchy of objects. I also have a view hierarchy with views that can extract required data from model objects and display the data (and allow the user to manipulate the data). Actually, there could be multiple view hierarchies that can represent and manipulate the model (e.g. an overview-detail view and a direct manipulation view). My current approach for this is for the controller layer to store a reference to the underlying model object in the View object. The view object can then get the current data from the model for display, and can send the model object messages to update the data. View objects are effectively observers of the model objects and the model objects broadcast notifications when properties change. This approach allows all the views to update simultaneously when any view changes the model. Implemented carefully, this all works. However, it does require a lot of work to ensure that no view or model objects hold any stale references to model objects. The user can delete model objects or sub-hierarchies of the model at any time. Ensuring that all the view objects that hold references to the model objects that have been deleted is time-consuming and difficult. It feels like the approach I have been taking is not especially clean; while I don't want to have to have explicit code in the controller layer for mediating the communication between the views and the model, it seems like there must be a better (implicit) approach for establishing bindings between the view and the model and between related model objects. In particular, I am looking for an approach (in C++) that understands two key points: There is a many to one relationship between view and model objects If the underlying model object is destroyed, all the dependent view objects must be cleaned up so that no stale references exist While shared_ptr and weak_ptr can be used to manage the lifetimes of the underlying model objects and allows for weak references from the view to the model, they don't provide for notification of the destruction of the underlying object (they do in the sense that the use of a stale weak_ptr allows for notification), but I need an approach that notifies the dependent objects that their weak reference is going away. Can anyone suggest a good strategy to manage this?

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  • Another question about handling game states

    - by Eva
    I'm making a game designed with the entity-component paradigm that uses systems to communicate between components as explained here. I've reached the point in my development that I need to add game states (such as paused, playing, level start, round start, game over, etc.), but I'm not sure how to do it with my framework. I've looked at this code example on game states which everyone seems to reference, but I don't think it fits with my framework. It seems to have each state handling its own drawing and updating. My framework has a SystemManager that handles all the updating using systems. For example, here's my RenderingSystem class: public class RenderingSystem extends GameSystem { private GameView gameView_; /** * Constructor * Creates a new RenderingSystem. * @param gameManager The game manager. Used to get the game components. */ public RenderingSystem(GameManager gameManager) { super(gameManager); } /** * Method: registerGameView * Registers gameView into the RenderingSystem. * @param gameView The game view registered. */ public void registerGameView(GameView gameView) { gameView_ = gameView; } /** * Method: triggerRender * Adds a repaint call to the event queue for the dirty rectangle. */ public void triggerRender() { Rectangle dirtyRect = new Rectangle(); for (GameObject object : getRenderableObjects()) { GraphicsComponent graphicsComponent = object.getComponent(GraphicsComponent.class); dirtyRect.add(graphicsComponent.getDirtyRect()); } gameView_.repaint(dirtyRect); } /** * Method: renderGameView * Renders the game objects onto the game view. * @param g The graphics object that draws the game objects. */ public void renderGameView(Graphics g) { for (GameObject object : getRenderableObjects()) { GraphicsComponent graphicsComponent = object.getComponent(GraphicsComponent.class); if (!graphicsComponent.isVisible()) continue; GraphicsComponent.Shape shape = graphicsComponent.getShape(); BoundsComponent boundsComponent = object.getComponent(BoundsComponent.class); Rectangle bounds = boundsComponent.getBounds(); g.setColor(graphicsComponent.getColor()); if (shape == GraphicsComponent.Shape.RECTANGULAR) { g.fill3DRect(bounds.x, bounds.y, bounds.width, bounds.height, true); } else if (shape == GraphicsComponent.Shape.CIRCULAR) { g.fillOval(bounds.x, bounds.y, bounds.width, bounds.height); } } } /** * Method: getRenderableObjects * @return The renderable game objects. */ private HashSet<GameObject> getRenderableObjects() { return gameManager.getGameObjectManager().getRelevantObjects( getClass()); } } Also all the updating in my game is event-driven. I don't have a loop like theirs that simply updates everything at the same time. I like my framework because it makes it easy to add new GameObjects, but doesn't have the problems some component-based designs encounter when communicating between components. I would hate to chuck it just to get pause to work. Is there a way I can add game states to my game without removing the entity-component design? Does the game state example actually fit my framework, and I'm just missing something?

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  • Functions returning pointers

    - by fg nu
    C++ noob here. I have a very basic question about a construct I found in the C++ book I am reading. // class declaration class CStr { char sData[256]; public: char* get(void); }; // implementation of the function char* CStr::get(void) { return sData; } So the Cstr::get function is obviously meant to return a character pointer, but the function is passing what looks like the value (return sData). Does C++ know to return the address of the returned object? My guess would have been that the function definition would be return &sData.

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  • Retrieve .Net Control ID in Javascript

    - by Vipin
    Originally posted on: http://geekswithblogs.net/Vipin/archive/2013/07/24/retrieve-.net-control-id-in-javascript.aspxIf you need to retrieve a client ID of an asp:net control in a javascript function, then you can use the below function - function $$(id, context) { var el = $("#" + id, context); if (el.length < 1) el = $("[id$=_" + id + "]", context); return el; }   var tempDotNetControl = 'aspTextTemporary';   var ClientSideID = $$(aspTextTemporary); Please bear in mind, this function is useful if you want to retrieve client ID of a different DotNet control based on some condition, otherwise if it’s always static then you can just use <%= aspTextTemporary.ClientID %>"

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