Search Results

Search found 107900 results on 4316 pages for 'new to java'.

Page 173/4316 | < Previous Page | 169 170 171 172 173 174 175 176 177 178 179 180  | Next Page >

  • Run java with highest security setting

    - by Ankiov Spetsnaz
    I'm currently writing an in house coding challenge web application and I am wondering if there is any other security precaution I would need to have other than below java option at runtime. java -Djava.security.manager=default Basically, challenges would be more of single threaded math and algorithm focused. So I would need to enable basic data structure objects and disable any file, sockets, threading or any thing that might be not so important. Based on my quick search turning on security manager as above seems to be a solution but since this is a security related I would like to be sure before it goes alive. Is there anything else I could do more?

    Read the article

  • A better way to do XML in Java

    - by jboyd
    There are a lot of questions that ask the best XML parser, I am more interested in what is the XML parser that is the most like Groovy for Java? I want: SomeApiDefinedObject o = parseXml( xml ); for( SomeApiDefinedObject it : o.getChildren() ) { System.out.println( it.getAttributes() ); } The most important things are that I don't want to create an object for every type of filed, I'd rather just deal with them all as strings, and that building the XML doesn't require any converters or anything, just a simple object that is already defined If you have used the Groovy XML parser, you will know what I'm talking about Alternatively, would it be better for me to just use Groovy from Java?

    Read the article

  • limit of connections with database and number of java threads in an application

    - by Jyoti
    Hi, I am working to develop a JMS application(stand alone multithreaded java application) which can receive 100 messages at a time , they need to be processed and database procedures need to be called for inserting/updating data. Procedures are very heavy as validations are also performed in them. Each procedure is taking about 30 to 50 seconds of time to execute and they are capable to run concurrently. My concern is to execute 100 procedures for all 100 messages and also send reply within time limit of 90 seconds by jms application. No application server to be used(requirement) and database is Teradata (RDBMS) I am using connection pool and thread pool in java code and testing code with 90 connections. Question is : (1) What should be the limit on number of connections with database at a time? (2) How many threads at a time are recommended? Thanks, Jyoti

    Read the article

  • The best alternative for String flyweight implementation in Java

    - by Dan
    My application is multithreaded with intensive String processing. We are experiencing excessive memory consumption and profiling has demonstrated that this is due to String data. I think that memory consumption would benefit greatly from using some kind of flyweight pattern implementation or even cache (I know for sure that Strings are often duplicated, although I don't have any hard data in that regard). I have looked at Java Constant Pool and String.intern, but it seems that it can provoke some PermGen problems. What would be the best alternative for implementing application-wide, multithreaded pool of Strings in java?

    Read the article

  • Java respawn process

    - by Bart van Heukelom
    I'm making an editor-like program. If the user chooses File-Open in the main window I want to start a new copy of the editor process with the chosen filename as an argument. However, for that I need to know what command was used to start the first process: java -jar myapp.jar blabalsomearguments // --- need this information Open File (fileUrl) exec("java -jar myapp.jar blabalsomearguments fileUrl"); I'm not looking for an in-process solution, I've already implemented that. I'd like to have the benefits that seperate processes bring.

    Read the article

  • Detect file system changes on Samba share with Java on Windows

    - by GHad
    Hi, for a recent project I need to detect file system changes on a mapped Samba share from java on windows: Creates, updates and removes. At the moment I am using a folder poll that maintains a list of files and their modified timestamp to look for events. But my problem is that this folder poll only peeks into the folder at certain times (every 10 seconds for example), so an updated file can be updated twice between two polls without recognizing. Is there any way to get events from windows inside Java whenever a file event occours on that mappep Samba share? Thanks!

    Read the article

  • Can I add elements to a Java GUI?

    - by Asj
    I want to know how I can make a java program where an unknown amount of objects can be added to a GUI depending on user input. I can program in objects one at a time within the program, but I haven't seen a more dynamic program. Can I do that with Java? If not, what can I do it with? For more information, here's a picture. http://i6.photobucket.com/albums/y223/Asj127/CapProjIdea.jpg There can be more than one question per question block, and each question can have it's own question block.

    Read the article

  • Writing Java code in Matlab?

    - by scooziexp
    Hi, I'm trying to use the Java commands pw.println() and br.readLine() in Matlab because I have set up a socket (input_socket2) between Matlab and a command-line program I want to control using Java classes BufferedReader and PrintWriter. Before the following snippet of code, I implemented another socket that goes between 2 computers. This works great and I also know that the following snippet of code successfully opens up a communication line between Matlab and the other program. However, Matlab throws an error at pw.println('noop'). I think it has something to do with syntax, but I'm not sure how to write the command in Matlab syntax then: try input_socket2 = Socket(host2,port2); input_stream2 = input_socket2.getInputStream; d_input_stream2 = DataInputStream(input_stream2); br = BufferedReader(InputStreamReader(input_stream2)); pw = PrintWriter(input_socket2.getOutputStream,true); pw.println('noop') br.read end Any ideas?

    Read the article

  • How does java LoginContext.login() work?

    - by tangens
    I have this code to create a configuration of a java client to connect to a JBoss application server: System.setProperty( "java.security.auth.login.config", "auth.conf" ); LoginContext auth = new LoginContext( "myAuth", new LoginCallbackHandler( username, password ) ); auth.login(); The file auth.conf contains the following lines: myAuth { org.jboss.security.ClientLoginModule required; }; Now, somewhere else in the code (the LoginContext auth isn't known there) I have an EJB that does a initialContext.lookup( jndiName ) and a narrow() to access a Bean on the JBoss application server. This narrow only succeeds if the login information of the first step was correct. Question How does the login information propagate from the LoginContext to the narrow()? I don't see any connection between these two places. And further, how could I do two or more different logins inside of one client?

    Read the article

  • Benchmark of Java Try/Catch Block

    - by hectorg87
    I know that going into a catch block has some significance cost when executing a program, however, I was wondering if entering a try{} block also had any impact so I started looking for an answer in google with many opinions, but no benchmarking at all. Some answers I found were: Java try/catch performance, is it recommended to keep what is inside the try clause to a minimum? Try Catch Performance Java Java try catch blocks However they didn't answer my question with facts, so I decided to try it for myself. Here's what I did. I have a csv file with this format: host;ip;number;date;status;email;uid;name;lastname;promo_code; where everything after status is optional and will not even have the corresponding ; , so when parsing a validation has to be done to see if the value is there, here's where the try/catch issue came to my mind. The current code that in inherited in my company does this: StringTokenizer st=new StringTokenizer(line,";"); String host = st.nextToken(); String ip = st.nextToken(); String number = st.nextToken(); String date = st.nextToken(); String status = st.nextToken(); String email = ""; try{ email = st.nextToken(); }catch(NoSuchElementException e){ email = ""; } and it repeats what it's done for email with uid, name, lastname and promo_code. and I changed everything to: if(st.hasMoreTokens()){ email = st.nextToken(); } and in fact it performs faster. When parsing a file that doesn't have the optional columns. Here are the average times: --- Trying:122 milliseconds --- Checking:33 milliseconds however, here's what confused me and the reason I'm asking: When running the example with values for the optional columns in all 8000 lines of the CSV, the if() version still performs better than the try/catch version, so my question is Does really the try block does not have any performance impact on my code? The average times for this example are: --- Trying:105 milliseconds --- Checking:43 milliseconds Can somebody explain what's going on here? Thanks a lot

    Read the article

  • Permissions error for a signed Java applet when including external JAR files

    - by sri
    I have a signed Java applet. And it works fine. But now I have to integrate some 3rd party JAR files with it. When I test it from Eclipse, the whole thing works correctly. But when I test it as an applet, it gives me a FilePermission error. I thought this was because those 3rd party JAR files don't have a java.policy.applet within them. But manually adding the policy file doesn't get rid of the error. What am I missing? Thanks! ============================ All the 3rd party JAR files sit on the server filesystem like so: A.jar, B.jar, C.jar. And I include them in the applet tag like so: <applet archive="my.jar,A.jar,B.jar,C.jar"> </applet> Also, in the MANIFEST/MANIFEST.MF file in my.jar, I include those JAR files like so: Class-Path: A.jar,B.jar,C.jar

    Read the article

  • Google appEngine: 404 when accesing /_ah/api

    - by jfu
    I try to build a very simple GAE application, using eclipse and the Google Plugin for Eclipse. I've generated some Endpoint from an @Entity class, then I've generated Cloud Endpoint Client library. After that I've started the appEngine project (within eclipse, on the embedded jetty server). When I try to access /_ah/api I get the following issue: HTTP ERROR 500 Problem accessing /_ah/api/. Reason: Failed to retrieve API configs with status: 404 Caused by: java.io.IOException: Failed to retrieve API configs with status: 404 at com.google.api.server.spi.tools.devserver.ApiServlet.getApiConfigSources(ApiServlet.java:102) at com.google.api.server.spi.tools.devserver.ApiServlet.initConfigsIfNecessary(ApiServlet.java:67) at com.google.api.server.spi.tools.devserver.RestApiServlet.service(RestApiServlet.java:117) at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) at com.google.appengine.api.socket.dev.DevSocketFilter.doFilter(DevSocketFilter.java:74) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.ResponseRewriterFilter.doFilter(ResponseRewriterFilter.java:123) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:34) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:63) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:125) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectRequest(DevAppServerModulesFilter.java:368) at com.google.appengine.tools.development.DevAppServerModulesFilter.doDirectModuleRequest(DevAppServerModulesFilter.java:351) at com.google.appengine.tools.development.DevAppServerModulesFilter.doFilter(DevAppServerModulesFilter.java:116) at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) What am I doing wrong?

    Read the article

  • what the java command's -jar option really does

    - by JBoy
    Does the -jar option of the java command also compile the sources before running the main method? I believe so but i would like to have a better understanding of the internal process, from the man page you can clearly see a small workflow sequence: -jar Execute a program encapsulated in a JAR file. The first argument is the name of a JAR file instead of a startup class name. In order for this option to work, the manifest of the JAR file must contain a line of the form Main-Class: classname. Here, classname identifies the class having the public static void main(String[] args) method that serves as your application's starting point. See the Jar tool reference page and the Jar trail of the Java Tutorial @ But it does not mention that it compiles the sources.

    Read the article

  • How to write web services in java

    - by gurupriyan.e
    Though this might appear as a duplicate of Java Web Services , I would like to know Where to start and to continue.In the past, I have invested so much of time to find where to start but I wasn't able to. There are so many jargons and chaos (at least for me!) while reading the pages about web services. There are so many terms - like JAX-RPC, JAX-WS, Axis, Rest, Servlet as WebService, EJB's as Web Service and other terms that I don't know. Can this User group consolidate and give a highlevel overview of Java Web Services which is easy to understand and follow? I appreciate your kindness and thanks for your help.

    Read the article

  • How to run AWS sample JAVA code on an EC2

    - by SeaPlusPlus
    I just started with Amazon web services, and I have an EC2 instance. I downloaded the JAVA SDK and the Eclipse toolbox. I am able to run a sample program locally on my PC and connect to the Amazon databases, etc. My question is, what do I need to do to get this working on my EC2 instance? This may not even be specific to AWS. On Eclipse, I can just "Run as Application" and run any code. On the server side, what do I need to do? Should I ftp over my .java files? Should I export it to a jar and upload that? Do I need to install anything special to actually run it? I'm just trying to run the basic DynamoDB example that connects to the database and adds a new table and row

    Read the article

  • Java EE - newbie question (not related to learning JEE)

    - by UnCon
    I've read lot of articles saying, that Java EE is most popular enterprise solution nowadays. Let's not argue if it is most popular or second most popular or what. The thing is : I see almost all web pages with extension like .html, .php and .aspx. Why there is (almost) none .JSP ? Why so ease to find ASP.NET pages if it is supposed to be less popular? Please I am not programming with Java EE (yet) so don't blame me, if I am completely wrong. The answer with patience would be greatly appreciated!

    Read the article

  • Is there a writable iterator in Java?

    - by Lukasz Lew
    In C+ one can use iterators for writing to a sequence. Simplest example would be: vector<int> v; for (vector<int>::iterator it = v.begin(); it!=v.end(); ++it) { *it = 42; } I need something more complicated - keep iterator as a class member for a later use. But I don't know how to get this behavior from Java iterators. Are there writable iterators in Java at all? If not then what replaces them?

    Read the article

< Previous Page | 169 170 171 172 173 174 175 176 177 178 179 180  | Next Page >