classloader

I'm seeing differences across platforms about when Class.forName() throws ClassNotFoundException and when it throws NoClassDefFoundError. Is this behavior well-defined somewhere, or have I stumbled across a bug? Consider the following code (which is a standalone java file in the default package): public class DLExceptionType { private static void printFindError(String name) { System.out.print(name + ": "); try { Class.forName(name); System.out.println("** no error **"); } catch (Throwable e) { System.out.println(e); } } public static void main(String[] args) { printFindError("DLExceptionType")

I am deploying a J2EE web application in Websphere Application Server 8.5. The web application has a shared library with all the third party libraries. All the internally coded libraries are inside the WEB-INF/lib folder. The problem is that in only some jsps WAS it is throwing the following exception. I think it is related with xercesImpl-2.8.1.jar but I don't understand why it is throwing this exception and why it is throwing in only some pages. In tomcat it is working perfectly. java.lang.ClassCastException: org.apache.xerces.jaxp.SAXParserFactoryImpl incompatible with javax.xml.parsers

I try to open file in jar in WEB-INF/lib with Thread.currentThread().getContextClassLoader(); URL url=classLoader.getResource(myconfig); In debugger I can see: jar:file:/C:/apache-tomcat/webapps/mywebapp/WEB-INF/lib/myjarresource.jar! /conf/configuration.xml Why in file path is "!" ? I think for this reason application cannot open this file. How to receive correct path? Thanks. It means whatever comes after the ! is inside the JAR file. In case of myjarresource.jar!/conf/configuration.xml , open up myjarresource.jar using a compression utility such as 7-zip and you will see that it contains

What happens when you have the same compiled class twice in a war deployed in tomcat? (I know it's not a good practice and so on, but what happens behind the scene?) Are there chances of nasty side-effects? I would expect the behaviour is the same as anywhere else you have that situation. The first class found by the class loader will be used, the other will be ignored. If you have one class is in WEB-INF/classes and the other in a jar, the one in WEB-INF/classes will have priority. If the two classes are in a jar, then one of them will be taken and the other ignored. The one that gets chosen

HERE IS THE HEAD DUMP (UPDATED ON 10/29/2013) I'm working in a webapp with: Tomcat 7.0.24 Java 6 Spring 3 (with aop - cglib) SLF4J over Log4j Oracle Coherence After a lot of work, I managed to remove all the strong reference to the class loader and now it is a candidate for the garbage collector. So, memory leak solved? Of course not! Because after several hot deployments a OOME appears due to PermGen space. Thanks to Yourkit, I was able to check that the WebappClassLoader was Pending Finalization which means that is waiting in the finalizer queue (actually, is not the WebappClassLoader itself

Consider a URLClassLoader parameterized with a collection of URL s which is a mix of expanded directories and jar files. For example: URL[] urls = new URL[] { new URL("file:/D:/work/temp/jars/spring-security-core-3.2.0.RELEASE.jar"), new URL("file:/D:/work/temp/jars/spring-security-config-3.2.0.RELEASE.jar"), ... new URL("file:/D:/work/temp/domain/bin/"), new URL("file:/D:/work/temp/web/bin/"), ... } URLClassLoader cl = new URLClassLoader(urls); The classloader correctly handles getResources() requests for resources located somewhere inside a package like "org/my/package/conf.properties" . By

I expose my context : I have two Java programs that run on a unique Weblogic Server : program A and program B. These ones are launched by two ksh : programA.ksh and programB.ksh Both need C.jar but in different versions (but with exactly the same package and classes) : program A need C-1.0.jar program B need C-2.0.jar I precise that both programs share the same weblogic classpath. So, my classpath contains in that order : ..... C-1.0.jar C-2.0.jar ..... How can I do so that each program finds its good library ? For instance, with my actual configuration, program B will always use C-1.0.jar

While loading a dll file, I am getting the following exception: Exception in thread "main" java.lang.UnsatisfiedLinkError: D:\Transliteration\rlpnc-3.1.0-sdk-ia32-w32-msvc80\rlp\bin\ia32-w32-msvc80\btrntjni.dll: The system cannot find message text for message number 0x%1 in the message file for %2 at java.lang.ClassLoader$NativeLibrary.load(Native Method) at java.lang.ClassLoader.loadLibrary0(Unknown Source) at java.lang.ClassLoader.loadLibrary(Unknown Source) at java.lang.Runtime.load0(Unknown Source) at java.lang.System.load(Unknown Source) at com.basistech.util.internal.Native.loadLibrary