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  • Technical Article: Experimenting with Java Timers

    - by Tori Wieldt
    OTN's new tech article is "Experimenting with Java Timers" by T. Lamine Ba. This article studies time—how Java handles timers and the scheduling of tasks. Java timers are utilities that let you execute threads or tasks at a predetermined future time, and these tasks can be repeated according to a set frequency. The article starts with a simple "Hello World" program in a web application that's composed of JavaServer Pages (JSP) and uses the model-control-view (MVC) design pattern. The IDE used in this article is NetBeans IDE 7.1, but you can use any IDE that supports Java. "Experimenting with Java Timers" demonstrates how to get started scheduling jobs with Java. To learn about Swing timers, check out the Java tutorial "How to Use Swing Timers" and additional information in the Java Platform, Standard Edition 7 API Specification for Class Timer. 

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  • How do you usually manage callbacks in Java using Swing library?

    - by none
    I'm quite new to the Java Swing programming, and GUI development as well. As a beginner, I'm currently reading Design Pattern, but finding what I'm looking for is quite hard, most of the times. So far, I've never had huge problems defining a view hierarchy - I just use to subclass component from component. But the hard-to-do here is how managing callbacks, which often become hard to maintain due to the hard code. During my last projects, I tried to separate GUI, Listener and Callbacker objects which cooperated together, but in this way it was really hard adding new features. So, which kind of best patterns or best practices do you tend to use when trying to maintain, add new features or even worst avoid to hard-code classes which manage callbacks method in this kind of frameworks (mainly Java Swing)?

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  • where can i learn to make 3d games in java from scratch?

    - by dfhgdfnhgfn
    Just wondering if anyone knows of anything i can read or watch that explains 3D graphics. i do not want to use any game engine like jogl etc. but i am looking for a way i can learn in detail how 3D works. preferably in java. I have used some game engines but would prefer to learn to make for myself. I would also like to do it without the java3d library. I have also watched some tutorials on 3d games in java, but would like to learn in more detail. Thanks.

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  • Java and Eclipse setup properly, how do I install JOGL or LWJGL?

    - by shadowprotocol
    I have my Java environment installed alongside Eclipse, and I was successfully able to create and run a new project (simple System.out.println("Yay I work!"); I have the OpenGL SuperBible, and I primarily want to code 3D things (I'll take my time using the book to learn how to draw shapes in 3D space, etc..) Can you help me get setup with OpenGL in Java? I dont really need LWJGL, although I WILL make games eventually. I just can't even figure out with all of these terrible (and old) tutorials floating around on the net how to install either JOGL or LWJGL. If you can give me a hand with that, I'd appreciate it. I'd like to feel I contributed by having this page show the answer to the question, so that other poor souls googling for this same information can benefit.

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  • How do I find a unit vector of another in Java?

    - by Shijima
    I'm writing a Java formula based on this tutorial: 2-D elastic collisions without Trigonometry. I am in the section "Elastic Collisions in 2 Dimensions". Part of step 1 says: Next, find the unit vector of n, which we will call un. This is done by dividing by the magnitude of n. My below code represents the normal vector of 2 objects (I'm using a simple array to represent the normal vector). int[] normal = new int[2]; normal[0] = ball2.x - ball1.x; normal[1] = ball2.y - ball1.y; I am unsure what the tutorial means by dividing the magnitude of n to get the un. What is un? How can I calculate it with my Java array?

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  • Why shouldn't I be using public variables in my Java class?

    - by Omega
    In school, I've been told many times to stop using public for my variables. I haven't asked why yet. This question: Are Java's public fields just a tragic historical design flaw at this point? seems kinda related to this. However, they don't seem to discuss why is it "wrong", but instead focus on how can they use them instead. Look at this (unfinished) class: public class Reporte { public String rutaOriginal; public String rutaNueva; public int bytesOriginales; public int bytesFinales; public float ganancia; /** * Constructor para objetos de la clase Reporte */ public Reporte() { } } No need to understand Spanish. All this class does is hold some statistics (those public fields) and then do some operations with them (later). I will also need to be modifying those variables often. But well, since I've been told not to use public, this is what I ended up doing: public class Reporte { private String rutaOriginal; private String rutaNueva; private int bytesOriginales; private int bytesFinales; private float ganancia; /** * Constructor para objetos de la clase Reporte */ public Reporte() { } public String getRutaOriginal() { return rutaOriginal; } public String getRutaNueva() { return rutaNueva; } public int getBytesOriginales() { return bytesOriginales; } public int getBytesFinales() { return bytesFinales; } public float getGanancia() { return ganancia; } public void setRutaOriginal(String rutaOriginal) { this.rutaOriginal = rutaOriginal; } public void setRutaNueva(String rutaNueva) { this.rutaNueva = rutaNueva; } public void setBytesOriginales(int bytesOriginales) { this.bytesOriginales = bytesOriginales; } public void setBytesFinales(int bytesFinales) { this.bytesFinales = bytesFinales; } public void setGanancia(float ganancia) { this.ganancia = ganancia; } } Looks kinda pretty. But seems like a waste of time. Google searches about "When to use public in Java" and "Why shouldn't I use public in Java" seem to discuss about a concept of mutability, although I'm not really sure how to interpret such discussions. I do want my class to be mutable - all the time.

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  • JUnit, Jenkins et Git seraient les outils préférés des développeurs Java, Java 8 adopté par 7% de développeurs

    JUnit, Jenkins et Git seraient les outils préférés des développeurs Java Java 8 adopté par 7% de développeurs, tandis que 26% utilisent encore Java 6L'écosystème Java dispose d'un nombre important d'outils et de piles logiciels qui sont utilisés au quotidien par les développeurs dans leurs applications.ZeroTurnaround, une entreprise spécialisée dans le développement d'outils à destination des développeurs Java, vient de publier son rapport annuel sur les outils et technologies de développement Java.L'étude...

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  • What's the reason in your mind Exception are heavily used in Managed (C# and Java) language but not in C++?

    - by ZijingWu
    AFAIK, a lot of C++ projects don't allow exceptions and deny them in coding guidelines. I have a lot of reasons, for example, Exception is hard to handle correctly if your binary needs to be compiled by separate and different compilers. But it doesn't fully convince me, there is a lot of projects which are just using one compiler. Compared to C++, Exceptions are heavily used in C# and Java and the reason can only be that Exception are not bringing enough benefit. One point is Debugbility in practice. Exception can not get the call stack in C++ code, but in C# and Java you can get the call stack from Exception, it is significant and makes debugging easier. No-CallStack is not the fault of the Exception, it is the language difference , but it impacts the Exception usage. So what's the reason that exceptions are frowned upon in c++ programs?

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  • Why do int when add up in java keeps on adding? [closed]

    - by Trycon
    I'm developing a game. I'm really new in java and researched google: why does an int when added, keeps on adding java Most of the times, it always adds even: STOP_DAMAGE+=1; Even sometimes, it subtract till negative. I'm annoyed. Sometimes it doesn't add too much. I do not understand. Here is my code: if(isPressed==true) { if(STOP_DAMAGE<=5) { if(WAIT_DAMAGE>=3000) { ENEMY_SHIP_HEALTH-=SHIP_DAMAGE_ENEMY; STOP_DAMAGE+=1; } } } for(;WAIT_DAMAGE>=3003;) { WAIT_DAMAGE-=WAIT_DAMAGE;//time is deducted } //WAIT_DAMAGE is a time int

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  • Is there any way around the field-of-use restrictions in Java?

    - by Muton
    Current field-of-use restrictions defined in "Oracle Binary Code License Agreement for the Java SE Platform Products" prohibit its use in embedded systems. "General Purpose Desktop Computers and Servers" means computers, including desktop and laptop computers, or servers, used for general computing functions under end user control (such as but not specifically limited to email, general purpose Internet browsing, and office suite productivity tools). The use of Software in systems and solutions that provide dedicated functionality (other than as mentioned above) or designed for use in embedded or function-specific software applications... are excluded from this definition and not licensed under this Agreement. Do these restrictions also apply to OpenJDK and other possible implementations? Is the only way to use Java in such an environment to acquire a separate license from Oracle?

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  • Java Magazine????5???

    - by sasa
    Java Magazine????5?????????????Java Magazine???????????????????????????????????? ?5????????????????Java Embedded????????? ????·???????? ????????? ??????? NetBeans?????Wicket 1.4??Web?????????? OPENJDK:?????? Java SE 7: ???????????????????????? JDK 7????Java DB???? OpenJDK??????Java?????????? Java HotSpot VM????JIT???????? JAVAFX2.0 ???????????????????? ???????????????? Java EE 6???????????? JavaFX????????? ??????????????????????????????????????????

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  • Java ??????????????

    - by katsumii
    ???????????java?????????????????????????????????? Linux,UNIX??? LANG ? LC_ALL ????????????????????????? Windows ????????????????????????????????????????????????????????????java -Duser.language=en ... ??????????????·??????????????????????????????java.exe????????????jvm.dll ?????????????????????????????????????????????????????java.exe???????????????????????????????????????????Windows: injecting argument to *.exe invocation (INOUE Katsumi @ Tokyo)There are many applications that spawns "java.exe" and there often is no way to pass java flags 

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  • ???????????Java SE 7??????! ?Java SE 7 ?????? ?????? ???!

    - by rika.tokumichi
    2006?Java SE6???????5????????????????????Java SE 7???????????????????????????????????????????2011?7?7???Java SE 7 ?????? ?????????????? ???????????????????????Java SE 7????????????????????????????????????????????Java????????????????1??????????????????? ????????????????????????????????? ?????????????Java SE 7????????Java SE8?????????????????????Java??????????????????HotSpot???JRockit??????Java???????????????????????????? ?????????????Java SE 7???????????Project Coin??InvokeDynamic??NIO.2??JSR-166y????????????????????????????????????? ????????????????????????????????????????????????????????????????????????????????? ???????????? Java SE 7 ??????????????????????????????Tips??????????????Java SE7????????????????????????????????????????????????? ??????????????????????Ustream?????????????????????! ???? Java SE 7 ?????? ?????? ??:2011?7?7?14?~ ??:?????????? 13F S3?S4 ?????(??) (????) 14:00 - 14:20????? 14:20 - 15:10Java SE 7?8??? 15:15 - 16:05HotRockit?Java?????????? 16:05 - 16:20?? (????) 16:20 - 17:05NetBeans 7.0?Project Coin??? 17:05 - 17:50InvokeDynamic??? 17:50 - 18:05?? 18:05 - 18:35NIO.2??? 18:35 - 19:05JSR 166y??? 19:05 -??? * ????????????????????????? ??????????????? ????????????

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  • ???????????Java SE 7??????! ?Java SE 7 ?????? ?????? ???!

    - by rika.tokumichi
    2006?Java SE6???????5????????????????????Java SE 7???????????????????????????????????????????2011?7?7???Java SE 7 ?????? ?????????????? ???????????????????????Java SE 7????????????????????????????????????????????Java????????????????1??????????????????? ????????????????????????????????? ?????????????Java SE 7????????Java SE8?????????????????????Java??????????????????HotSpot???JRockit??????Java???????????????????????????? ?????????????Java SE 7???????????Project Coin??InvokeDynamic??NIO.2??JSR-166y????????????????????????????????????? ????????????????????????????????????????????????????????????????????????????????? ???????????? Java SE 7 ??????????????????????????????Tips??????????????Java SE7????????????????????????????????????????????????? ??????????????????????Ustream?????????????????????! ???? Java SE 7 ?????? ?????? ??:2011?7?7?14?~ ??:?????????? 13F S3?S4 ?????(??) (????) 14:00 - 14:20????? 14:20 - 15:10Java SE 7?8??? 15:15 - 16:05HotRockit?Java?????????? 16:05 - 16:20?? (????) 16:20 - 17:05NetBeans 7.0?Project Coin??? 17:05 - 17:50InvokeDynamic??? 17:50 - 18:05?? 18:05 - 18:35NIO.2??? 18:35 - 19:05JSR 166y??? 19:05 -??? * ????????????????????????? ??????????????? ????????????

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  • ???????/???Java EE 6 ??

    - by Yusuke.Yamamoto
    ????? ??:2011/04/01 ??:??????/?? Java EE 6 ?2009?12??????????????1???????????1???Java EE 6 ?????????????????????????????????????? Java EE ????????????????????????????????????Java EE 6 ? JBoss Seam, Hibernate, Web Beans(CDI) ????????????????????????????????????????????????????????? Java EE 6 ??????????Java EE 6 ???????? GlassFish ????????????????????????? Java EE 6 ???Managed Bean 1.0 / Interceptor 1.1Servlet 3.0JSF 2.0EJB 3.1JPA 2.0JAX-RS 1.1Bean ValidationDI/CDIJava EE 7 ????:???? ????????? ????????????????? http://otndnld.oracle.co.jp/ondemand/otn-seminar/movie/id_000887.wmv http://www.oracle.com/technetwork/jp/ondemand/java/id-000888-365852-ja.pdf

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  • Overwrite archetypes in Maven

    - by Random
    Hello again! I'm having some trouble using Maven for my archetypes and I will need to overwrite some. I launch an instruction that does an archetype:generate in an archetype already existing directory. Is there a parameter that let's me overwrite existing archetypes? I have search the maven definitve guide but it states that the only parameters accepted are: -DgroupId -DartifactId -Dversion -DpackageName -DarchetypeGroupId -DarchetypeArtifactId -DarchetypeVersion -DinteractiveMode I could just search the directory and delete the files, but this proccess is going to be done automatically (so no human involved, no brains involved) and I wouldn't like he machine deleting things around. Thanks for all! Edit: I almost forgot, here is some maven trace: [INFO] Scanning for projects... [INFO] Searching repository for plugin with prefix: 'archetype'. [INFO] ------------------------------------------------------------------------ [INFO] Building Maven Default Project [INFO] task-segment: [archetype:generate] (aggregator-style) [INFO] ------------------------------------------------------------------------ [INFO] Preparing archetype:generate [INFO] No goals needed for project - skipping [INFO] Setting property: classpath.resource.loader.class => 'org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader'. [INFO] Setting property: velocimacro.messages.on => 'false'. [INFO] Setting property: resource.loader => 'classpath'. [INFO] Setting property: resource.manager.logwhenfound => 'false'. [INFO] [archetype:generate {execution: default-cli}] [INFO] Generating project in Batch mode [INFO] Archetype defined by properties [INFO] ---------------------------------------------------------------------------- [INFO] Using following parameters for creating OldArchetype: archetype-foo-lib:1.0 [INFO] ---------------------------------------------------------------------------- [INFO] Parameter: groupId, Value: foo.tecnologia [INFO] Parameter: packageName, Value: foo.tecnologia [INFO] Parameter: basedir, Value: C:\temp\Desarrollo [INFO] Parameter: package, Value: foo.tecnologia [INFO] Parameter: version, Value: 1.0 [INFO] Parameter: artifactId, Value: Foo-Lib-Test [ERROR] Directory Foo-Lib-Test already exists - please run from a clean directory org.apache.maven.archetype.old.ArchetypeTemplateProcessingException: Directory Foo-Lib-Test already exists - please run from a clean directory at org.apache.maven.archetype.old.DefaultOldArchetype.createArchetype(DefaultOldArchetype.java:242) at org.apache.maven.archetype.generator.DefaultArchetypeGenerator.processOldArchetype(DefaultArchetypeGenerator.java:253) at org.apache.maven.archetype.generator.DefaultArchetypeGenerator.generateArchetype(DefaultArchetypeGenerator.java:143) at org.apache.maven.archetype.generator.DefaultArchetypeGenerator.generateArchetype(DefaultArchetypeGenerator.java:286) at org.apache.maven.archetype.DefaultArchetype.generateProjectFromArchetype(DefaultArchetype.java:69) at org.apache.maven.archetype.mojos.CreateProjectFromArchetypeMojo.execute(CreateProjectFromArchetypeMojo.java:184) at org.apache.maven.plugin.DefaultPluginManager.executeMojo(DefaultPluginManager.java:490) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:694) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeStandaloneGoal(DefaultLifecycleExecutor.java:569) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoal(DefaultLifecycleExecutor.java:539) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalAndHandleFailures(DefaultLifecycleExecutor.java:387) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeTaskSegments(DefaultLifecycleExecutor.java:284) at org.apache.maven.lifecycle.DefaultLifecycleExecutor.execute(DefaultLifecycleExecutor.java:180) at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:328) at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:138) at com.foo.model.CSMavenCli.main(CSMavenCli.java:391) at com.foo.model.MavenAdmin.generateArchetype(MavenAdmin.java:399) at com.foo.model.ValidarPom.validarPom(ValidarPom.java:167) at com.foo.prueba.GenerarPOM.execute(GenerarPOM.java:93) at org.apache.struts.chain.commands.servlet.ExecuteAction.execute(ExecuteAction.java:58) at org.apache.struts.chain.commands.AbstractExecuteAction.execute(AbstractExecuteAction.java:67) at org.apache.struts.chain.commands.ActionCommandBase.execute(ActionCommandBase.java:51) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:191) at org.apache.commons.chain.generic.LookupCommand.execute(LookupCommand.java:305) at org.apache.commons.chain.impl.ChainBase.execute(ChainBase.java:191) at org.apache.struts.chain.ComposableRequestProcessor.process(ComposableRequestProcessor.java:283) at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1913) at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:462) at javax.servlet.http.HttpServlet.service(HttpServlet.java:647) at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:172) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:174) at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:873) at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665) at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528) at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689) at java.lang.Thread.run(Unknown Source) [INFO] ------------------------------------------------------------------------ [ERROR] BUILD FAILURE [INFO] ------------------------------------------------------------------------ [INFO] : org.apache.maven.archetype.old.ArchetypeTemplateProcessingException: Directory Foo-Lib-Test already exists - please run from a clean directory Directory Foo-Lib-Test already exists - please run from a clean directory [INFO] ------------------------------------------------------------------------ [INFO] For more information, run Maven with the -e switch [INFO] ------------------------------------------------------------------------ [INFO] Total time: 1 second [INFO] Finished at: Fri Apr 09 10:01:33 CEST 2010 [INFO] Final Memory: 15M/28M [INFO] ------------------------------------------------------------------------

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  • Provider<HttpSession> not getting injected

    - by user1033715
    I am using gwt dispatch to communicate and get data from server to client. In order to get user specific data I want to store the user object in httpsession and access application specific data from servlet context but when I inject Provider<HttpSession> when the handler execute is called but the dispatchservlet the provider is null i.e it does not get injected. following is the code from my action handler @Inject Provider<HttpSession> provider; public ReadEntityHandler() { } @Override public EntityResult execute(ReadEntityAction arg0, ExecutionContext arg1) throws DispatchException { HttpSession session = null; if (provider == null) System.out.println("httpSession is null.."); else { session = provider.get(); System.out.println("httpSession not null.."); } System.out.println("reached execution"); return null; } and my Dispatch servlet @Singleton public class ActionDispatchServlet extends RemoteServiceServlet implements StandardDispatchService { private Dispatch dispatch; public ActionDispatchServlet() { InstanceActionHandlerRegistry registry = new DefaultActionHandlerRegistry(); registry.addHandler(new ReadEntityHandler()); dispatch = new SimpleDispatch(registry); } @Override public Result execute(Action<?> action) throws DispatchException { try { return dispatch.execute(action); } catch (RuntimeException e) { log("Exception while executing " + action.getClass().getName() + ": " + e.getMessage(), e); throw e; } } } when I try to inject the ReadEntityHandler it throws the following exception [WARN] failed guiceFilter com.google.inject.ProvisionException: Guice provision errors: 1) Error injecting constructor, java.lang.NullPointerException at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:22) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.class(ActionDispatchServlet.java:22) while locating com.ensarm.wikirealty.server.service.ActionDispatchServlet 1 error at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:834) at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:856) at com.google.inject.servlet.ServletDefinition.init(ServletDefinition.java:74) at com.google.inject.servlet.ManagedServletPipeline.init(ManagedServletPipeline.java:84) at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:106) at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:168) at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593) at org.mortbay.jetty.servlet.Context.startContext(Context.java:140) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448) at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130) at org.mortbay.jetty.Server.doStart(Server.java:222) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39) at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672) at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509) at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068) at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811) at com.google.gwt.dev.DevMode.main(DevMode.java:311) Caused by: java.lang.NullPointerException at net.customware.gwt.dispatch.server.DefaultActionHandlerRegistry.addHandler(DefaultActionHandlerRegistry.java:21) at com.ensarm.wikirealty.server.service.ActionDispatchServlet.<init>(ActionDispatchServlet.java:24) at com.ensarm.wikirealty.server.service.ActionDispatchServlet$$FastClassByGuice$$e0a28a5d.newInstance(<generated>) at com.google.inject.internal.cglib.reflect.FastConstructor.newInstance(FastConstructor.java:40) at com.google.inject.internal.DefaultConstructionProxyFactory$1.newInstance(DefaultConstructionProxyFactory.java:58) at com.google.inject.internal.ConstructorInjector.construct(ConstructorInjector.java:84) at com.google.inject.internal.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:200) at com.google.inject.internal.ProviderToInternalFactoryAdapter$1.call(ProviderToInternalFactoryAdapter.java:43) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:878) at com.google.inject.internal.ProviderToInternalFactoryAdapter.get(ProviderToInternalFactoryAdapter.java:40) at com.google.inject.Scopes$1$1.get(Scopes.java:64) at com.google.inject.internal.InternalFactoryToProviderAdapter.get(InternalFactoryToProviderAdapter.java:40) at com.google.inject.internal.InjectorImpl$4$1.call(InjectorImpl.java:825) at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:871) at com.google.inject.internal.InjectorImpl$4.get(InjectorImpl.java:821) ... 25 more

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  • Classcastexception occurs randomly

    - by kjhari02
    Hi, I've an application in the market and many users have reported that the app is crashing a lot randomly. I'm trying to fix this but cannot fully understand the logs. Here's a extract from the log, 04-16 13:16:32.407 E/AndroidRuntime( 9237): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.maya.mobile.chiki/com.maya.mobile.chiki.tabview.Tabs3}: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.maya.mobile.chiki/com.maya.mobile.chiki.featured.FeaturedView}: java.lang.ClassCastException: android.view.AbsSavedState$1 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.access$2200(ActivityThread.java:119) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.os.Handler.dispatchMessage(Handler.java:99) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.os.Looper.loop(Looper.java:123) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.main(ActivityThread.java:4363) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at java.lang.reflect.Method.invokeNative(Native Method) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at java.lang.reflect.Method.invoke(Method.java:521) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at dalvik.system.NativeStart.main(Native Method) 04-16 13:16:32.407 E/AndroidRuntime( 9237): Caused by: java.lang.RuntimeException: Unable to start activity ComponentInfo{com.maya.mobile.chiki/com.maya.mobile.chiki.featured.FeaturedView}: java.lang.ClassCastException: android.view.AbsSavedState$1 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.startActivityNow(ActivityThread.java:2335) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:127) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:339) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:648) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.widget.TabHost.setCurrentTab(TabHost.java:320) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.maya.mobile.chiki.tabview.CustomTabHost.setCurrentTab(CustomTabHost.java:43) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.widget.TabHost.addTab(TabHost.java:213) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.maya.mobile.chiki.tabview.Tabs3.doCreateTabs(Tabs3.java:180) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.maya.mobile.chiki.tabview.Tabs3.onCreate(Tabs3.java:149) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459) 04-16 13:16:32.407 E/AndroidRuntime( 9237): ... 11 more 04-16 13:16:32.407 E/AndroidRuntime( 9237): Caused by: java.lang.ClassCastException: android.view.AbsSavedState$1 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.widget.AbsSpinner.onRestoreInstanceState(AbsSpinner.java:440) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.View.dispatchRestoreInstanceState(View.java:5940) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.ViewGroup.dispatchThawSelfOnly(ViewGroup.java:1140) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.widget.AdapterView.dispatchRestoreInstanceState(AdapterView.java:767) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:1127) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:1127) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:1127) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:1127) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.view.View.restoreHierarchyState(View.java:5919) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at com.android.internal.policy.impl.PhoneWindow.restoreHierarchyState(PhoneWindow.java:1454) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.Activity.onRestoreInstanceState(Activity.java:835) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.Activity.performRestoreInstanceState(Activity.java:807) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1096) 04-16 13:16:32.407 E/AndroidRuntime( 9237): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2473) 04-16 13:16:32.407 E/AndroidRuntime( 9237): ... 22 more I got this log from one of my users. Any help on this would be very very helpful. Regards, Hari

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  • problem in start up my RMI server(under ISP) so that it can recieve remote calls over Internet.--Jav

    - by Lokesh Kumar
    i m creating a Client/Server application in which my server and client can be on the same or on different machines but both are under ISP. My RMI programs:- -Remote Intreface:- //Calculator.java public interface Calculator extends java.rmi.Remote { public long add(long a, long b) throws java.rmi.RemoteException; public long sub(long a, long b) throws java.rmi.RemoteException; public long mul(long a, long b) throws java.rmi.RemoteException; public long div(long a, long b) throws java.rmi.RemoteException; } Remote Interface Implementation:- //CalculatorImpl.java public class CalculatorImpl extends java.rmi.server.UnicastRemoteObject implements Calculator { public CalculatorImpl() throws java.rmi.RemoteException { super(); } public long add(long a, long b) throws java.rmi.RemoteException { return a + b; } public long sub(long a, long b) throws java.rmi.RemoteException { return a - b; } public long mul(long a, long b) throws java.rmi.RemoteException { return a * b; } public long div(long a, long b) throws java.rmi.RemoteException { return a / b; } } Server:- //CalculatorServer.java import java.rmi.Naming; import java.rmi.server.RemoteServer; public class CalculatorServer { public CalculatorServer() { try { Calculator c = new CalculatorImpl(); Naming.rebind("rmi://"+args[0]+":1099/CalculatorService", c); } catch (Exception e) { System.out.println("Trouble: " + e); } } public static void main(String args[]) { new CalculatorServer(); } } Client:- //CalculatorClient.java import java.rmi.Naming; import java.rmi.RemoteException; import java.net.MalformedURLException; import java.rmi.NotBoundException; public class CalculatorClient { public static void main(String[] args) { try { Calculator c = (Calculator)Naming.lookup("rmi://"+args[0]+"/CalculatorService"); System.out.println( c.sub(4, 3) ); System.out.println( c.add(4, 5) ); System.out.println( c.mul(3, 6) ); System.out.println( c.div(9, 3) ); } catch (MalformedURLException murle) { System.out.println(); System.out.println("MalformedURLException"); System.out.println(murle); } catch (RemoteException re) { System.out.println(); System.out.println("RemoteException"); System.out.println(re); } catch (NotBoundException nbe) { System.out.println(); System.out.println("NotBoundException"); System.out.println(nbe); } catch (java.lang.ArithmeticException ae) { System.out.println(); System.out.println("java.lang.ArithmeticException"); System.out.println(ae); } } } when both Server and client programs are on same machine:- i start my server program by passing my router static IP address:-192.168.1.35 in args[0] and my server starts...fine. and by passing the same Static IP address in my Client's args[0] also works fine. but:- when both Server and client programs are on different machines:- now,i m trying to start my Server Program by passing it's public IP address:59.178.198.247 in args[0] so that it can recieve call over internet. but i am unable to start it. and the following exception occurs:- Trouble: java.rmi.ConnectException: Connection refused to host: 59.178.198.247; nested exception is: java.net.ConnectException: Connection refused: connect i think it is due to NAT Problem because i am under ISP. so,my problem is that how can i start my RMI Server under ISP so that it can recieve remote calls from internet????

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  • Neo4j OutOfMemory problem

    - by Edward83
    Hi! This is my source code of Main.java. It was grabbed from neo4j-apoc-1.0 examples. The goal of modification to store 1M records of 2 nodes and 1 relation: package javaapplication2; import org.neo4j.graphdb.GraphDatabaseService; import org.neo4j.graphdb.Node; import org.neo4j.graphdb.RelationshipType; import org.neo4j.graphdb.Transaction; import org.neo4j.kernel.EmbeddedGraphDatabase; public class Main { private static final String DB_PATH = "neo4j-store-1M"; private static final String NAME_KEY = "name"; private static enum ExampleRelationshipTypes implements RelationshipType { EXAMPLE } public static void main(String[] args) { GraphDatabaseService graphDb = null; try { System.out.println( "Init database..." ); graphDb = new EmbeddedGraphDatabase( DB_PATH ); registerShutdownHook( graphDb ); System.out.println( "Start of creating database..." ); int valIndex = 0; for(int i=0; i<1000; ++i) { for(int j=0; j<1000; ++j) { Transaction tx = graphDb.beginTx(); try { Node firstNode = graphDb.createNode(); firstNode.setProperty( NAME_KEY, "Hello" + valIndex ); Node secondNode = graphDb.createNode(); secondNode.setProperty( NAME_KEY, "World" + valIndex ); firstNode.createRelationshipTo( secondNode, ExampleRelationshipTypes.EXAMPLE ); tx.success(); ++valIndex; } finally { tx.finish(); } } } System.out.println("Ok, client processing finished!"); } finally { System.out.println( "Shutting down database ..." ); graphDb.shutdown(); } } private static void registerShutdownHook( final GraphDatabaseService graphDb ) { // Registers a shutdown hook for the Neo4j instance so that it // shuts down nicely when the VM exits (even if you "Ctrl-C" the // running example before it's completed) Runtime.getRuntime().addShutdownHook( new Thread() { @Override public void run() { graphDb.shutdown(); } } ); } } After a few iterations (around 150K) I got error message: "java.lang.OutOfMemoryError: Java heap space at java.nio.HeapByteBuffer.(HeapByteBuffer.java:39) at java.nio.ByteBuffer.allocate(ByteBuffer.java:312) at org.neo4j.kernel.impl.nioneo.store.PlainPersistenceWindow.(PlainPersistenceWindow.java:30) at org.neo4j.kernel.impl.nioneo.store.PersistenceWindowPool.allocateNewWindow(PersistenceWindowPool.java:534) at org.neo4j.kernel.impl.nioneo.store.PersistenceWindowPool.refreshBricks(PersistenceWindowPool.java:430) at org.neo4j.kernel.impl.nioneo.store.PersistenceWindowPool.acquire(PersistenceWindowPool.java:122) at org.neo4j.kernel.impl.nioneo.store.CommonAbstractStore.acquireWindow(CommonAbstractStore.java:459) at org.neo4j.kernel.impl.nioneo.store.AbstractDynamicStore.updateRecord(AbstractDynamicStore.java:240) at org.neo4j.kernel.impl.nioneo.store.PropertyStore.updateRecord(PropertyStore.java:209) at org.neo4j.kernel.impl.nioneo.xa.Command$PropertyCommand.execute(Command.java:513) at org.neo4j.kernel.impl.nioneo.xa.NeoTransaction.doCommit(NeoTransaction.java:443) at org.neo4j.kernel.impl.transaction.xaframework.XaTransaction.commit(XaTransaction.java:316) at org.neo4j.kernel.impl.transaction.xaframework.XaResourceManager.commit(XaResourceManager.java:399) at org.neo4j.kernel.impl.transaction.xaframework.XaResourceHelpImpl.commit(XaResourceHelpImpl.java:64) at org.neo4j.kernel.impl.transaction.TransactionImpl.doCommit(TransactionImpl.java:514) at org.neo4j.kernel.impl.transaction.TxManager.commit(TxManager.java:571) at org.neo4j.kernel.impl.transaction.TxManager.commit(TxManager.java:543) at org.neo4j.kernel.impl.transaction.TransactionImpl.commit(TransactionImpl.java:102) at org.neo4j.kernel.EmbeddedGraphDbImpl$TransactionImpl.finish(EmbeddedGraphDbImpl.java:329) at javaapplication2.Main.main(Main.java:62) 28.05.2010 9:52:14 org.neo4j.kernel.impl.nioneo.store.PersistenceWindowPool logWarn WARNING: [neo4j-store-1M\neostore.propertystore.db.strings] Unable to allocate direct buffer" Guys! Help me plzzz, what I did wrong, how can I repair it? Tested on platform Windows XP 32bit SP3. Maybe solution within creation custom configuration? thnx 4 every advice!

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  • Piping input to a Java app with Perl

    - by user319479
    I need to write a Perl script that pipes input into a Java program. This is related to this, but that didn't help me. My issue is that the Java app doesn't get the print statements until I close the handle. What I found online was that $| needs to be set to something greater than 0, in which case newline characters will flush the buffer. This still doesn't work. This is the script: #! /usr/bin/perl -w use strict; use File::Basename; $|=1; open(TP, "| java -jar test.jar") or die "fail"; sleep(2); print TP "this is test 1\n"; print TP "this is test 2\n"; print "tests printed, waiting 5s\n"; sleep(5); print "wait over. closing handle...\n"; close TP; print "closed.\n"; print "sleeping for 5s...\n"; sleep(5); print "script finished!\n"; exit And here is a sample Java app: import java.util.Scanner; public class test{ public static void main( String[] args ){ Scanner sc = new Scanner( System.in ); int crashcount = 0; while( true ){ try{ String input = sc.nextLine(); System.out.println( ":: INPUT: " + input ); if( "bananas".equals(input) ){ break; } } catch( Exception e ){ System.out.println( ":: EXCEPTION: " + e.toString() ); crashcount++; if( crashcount == 5 ){ System.out.println( ":: Looks like stdin is broke" ); break; } } } System.out.println( ":: IT'S OVER!" ); return; } } The Java app should respond to receiving the test prints immediately, but it doesn't until the close statement in the Perl script. What am I doing wrong? Note: the fix can only be in the Perl script. The Java app can't be changed. Also, File::Basename is there because I'm using it in the real script.

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  • Java unchecked method invocation

    - by Sam
    I'm trying to setup a multithreaded application using SQLite4java, and everything is working fine. However, according to the getting started tutorial I am meant to create an object of type "object" and in order to return a value of null (due to use of generic types). Here is the suggested code: queue.execute(new SQLiteJob<Object>() { protected Object job(SQLiteConnection connection) throws SQLiteException { // this method is called from database thread and passed the connection connection.exec(...); return null; } }); Source The following example code I created produces the same error: error: test.java:9: warning: [unchecked] unchecked method invocation: <T,J>execute(J) in com.almworks.sqlite4java.SQLiteQueue is applied to (query<java.lang.Integer>) queue.execute(new query<Integer>()); test.java: import com.almworks.sqlite4java.*; import java.util.ArrayList; import java.io.File; class test{ public static void main(String[] args){ File f = new File("file.db"); SQLiteQueue queue = new SQLiteQueue(f); queue.execute(new query<Integer>()); } } query.java: import com.almworks.sqlite4java.SQLiteException; import com.almworks.sqlite4java.SQLiteJob; import com.almworks.sqlite4java.SQLiteConnection; import com.almworks.sqlite4java.SQLiteStatement; import java.util.ArrayList; class query<T> extends SQLiteJob{ protected ArrayList<Integer> job(SQLiteConnection connection) throws SQLiteException{ ArrayList<Integer> ints = new ArrayList<Integer>(); //DB Stuff return ints; } } I have read a lot about how this particular message appears when people fail to specify a type for an ArrayList. However, I am not attempting to cast the object or do anything with it. It is merely a mechanism implemented by the library developers in order to return a null. I do not believe this to be an issue relating directly to the library, which is why I'm asking this on StackOverflow. I believe it all comes down to my lack of experience with generic types. I've already spent a few hours on this and don't feel like I am getting anywhere. How do I stop the warning?

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  • How to record / capture audio with RecordControl on Java ME, SE K770i

    - by tomaszs
    I want to record sound on my Java ME App on K770i. So I used this: http://java.sun.com/javame/reference/apis/jsr135/javax/microedition/media/control/RecordControl.html example of RecordControl in my code. It goes like this: import java.util.Vector; import javax.microedition.lcdui.Choice; import javax.microedition.lcdui.Command; import javax.microedition.lcdui.CommandListener; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.Displayable; import javax.microedition.lcdui.List; import javax.microedition.media.Manager; import javax.microedition.media.MediaException; import javax.microedition.midlet.MIDlet; import java.io.*; import javax.microedition.lcdui.*; import javax.microedition.media.*; import javax.microedition.media.control.*; import javax.microedition.midlet.*; import javax.microedition.rms.*; (...) try { // Create a Player that captures live audio. Player p = Manager.createPlayer("capture://audio"); p.realize(); // Get the RecordControl, set the record stream, // start the Player and record for 5 seconds. RecordControl rc = (RecordControl)p.getControl("RecordControl"); ByteArrayOutputStream output = new ByteArrayOutputStream(); rc.setRecordStream(output); rc.startRecord(); p.start(); Thread.currentThread().sleep(5000); rc.commit(); p.close(); } catch (IOException ioe) { } catch (MediaException me) { } catch (InterruptedException ie) { } But unfortunately when I try to build it, it tells me: *** Creating directories *** *** Compiling source files *** ..\src\example\audiodemo\AudioPlayer.java:121: cannot find symbol symbol : class RecordControl location: class example.audiodemo.AudioPlayer RecordControl rc = (RecordControl)p.getControl("RecordControl"); ^ ..\src\example\audiodemo\AudioPlayer.java:121: cannot find symbol symbol : class RecordControl location: class example.audiodemo.AudioPlayer RecordControl rc = (RecordControl)p.getControl("RecordControl"); ^ 2 errors So my question is: why there is no RecordControl class if in documentations it is written this class should be there. Or is there other method to record / capture audio from microfone in Java ME of Sony Ericsson? How do you record sound?

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  • Java app makes screen display unresponsive after 10 minutes of user idle time

    - by Ross
    I've written a Java app that allows users to script mouse/keyboard input (JMacro, link not important, only for the curious). I personally use the application to automate character actions in an online game overnight while I sleep. Unfortunately, I keep coming back to the computer in the morning to find it unresponsive. Upon further testing, I'm finding that my application causes the computer to become unresponsive after about 10 minutes of user idle time (even if the application itself it simulating user activity). I can't seem to pin-point the issue, so I'm hoping somebody else might have a suggestion of where to look or what might be causing the issue. The relevant symptoms and characteristics: Unresponsiveness occurs after user is idle for 10 minutes User can still move the mouse pointer around the screen Everything but the mouse appears frozen... mouse clicks have no effect and no applications update their displays, including the Windows 7 desktop I left the task manager up along the with the app overnight so I could see the last task manager image before the screen freezes... the Java app is at normal CPU/Memory usage and total CPU usage is only ~1% After moving the mouse (in other words, the user comes back from being idle), the screen image starts updating again within 30 minutes (this is very hit and miss... sometimes 10 minutes, sometimes no results after two hours) User can CTRL-ALT-DEL to get to Windows 7's CTRL-ALT-DEL screen (after a 30 second pause). User is still able to move mouse pointer, but clicking any of the button options causes the screen to appear to freeze again On some very rare occasions, the system never freezes, and I come back to it in the morning with full responsiveness The Java app automatically stops input scripting in the middle of the night, so Windows 7 detects "real" idleness and turns the monitors into Standby mode... which they successfully come out of upon manually moving the mouse in the morning when I wake up, even though the desktop display still appears frozen Given the symptoms and characteristics of the issue, it's as if the Java app is causing the desktop display of the logged in user to stop updating, including any running applications. Programming concepts and Java packages used: Multi-threading Standard out and err are rerouted to a javax.swing.JTextArea The application uses a Swing GUI awt.Robot (very heavily used) awt.PointerInfo awt.MouseInfo System Specs: Windows 7 Professional Java 1.6.0 u17 In conclusion, I should stress that I'm not looking for any specific solutions, as I'm not asking a very specific question. I'm just wondering if anybody has run into a similar problem when using the Java libraries that I'm using. I would also gladly appreciate any suggestions for things to try to attempt to further pinpoint what is causing my problem. Thanks! Ross PS, I'll post an update/answer if I manage to stumble across anything else while I continue to debug this.

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  • stringindexoutofbounds with currency converter java program

    - by user1795926
    I am have trouble with a summary not showing up. I am supposed to modify a previous Java assignment by by adding an array of objects. Within the loop, instantiate each individual object. Make sure the user cannot keep adding another Foreign conversion beyond your array size. After the user selects quit from the menu, prompt if the user want to display a summary report. If they select ‘Y’ then, using your array of objects, display the following report: Item Conversion Dollars Amount 1 Japanese Yen 100.00 32,000.00 2 Mexican Peso 400.00 56,000.00 3 Canadian Dollar 100.00 156.00 etc. Number of Conversions = 3 There are no errors when I compile..but when I run the program it is fine until I hit 0 to end the conversion and have it ask if i want to see a summary. This error displays: Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 0 at java.lang.String.charAt(String.java:658) at Lab8.main(Lab8.java:43) my code: import java.util.Scanner; import java.text.DecimalFormat; public class Lab8 { public static void main(String[] args) { final int Max = 10; String a; char summary; int c = 0; Foreign[] Exchange = new Foreign[Max]; Scanner Keyboard = new Scanner(System.in); Foreign.opening(); do { Exchange[c] = new Foreign(); Exchange[c].getchoice(); Exchange[c].dollars(); Exchange[c].amount(); Exchange[c].vertical(); System.out.println("\n" + Exchange[c]); c++; System.out.println("\n" + "Please select 1 through 4, or 0 to quit" + >"\n"); c= Keyboard.nextInt(); } while (c != 0); System.out.print("\nWould you like a summary of your conversions? (Y/N): "); a = Keyboard.nextLine(); summary = a.charAt(0); summary = Character.toUpperCase(summary); if (summary == 'Y') { System.out.println("\nCountry\t\tRate\t\tDollars\t\tAmount"); System.out.println("========\t\t=======\t\t=======\t\t========="); for (int i=0; i < Exchange.length; i++) System.out.println(Exchange[i]); Foreign.counter(); } } } I looked at line 43 and its this line: summary = a.charAt(0); But I am not sure what's wrong with it, can anyone point it out? Thank you.

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