classnotfoundexception

I developed an eclipse plugin and I'm trying to install it on another instance of eclipse. When I run/debug my plugin as an eclipse application everything works correctly. The problem occurs only after I install the plugin through the update site I created. I created a very simple update site which includes a single feature with my plugin packaged in it. After installing using the update site I can see my plugin in the plugin directory under the eclipse install dir and it correctly contains all the data that should be in there (I think). However, when I instantiate the plugin (by hitting the

I am starting a java and tomcat based application. I am getting the following error. Dec 08, 2015 12:04:00 PM org.apache.catalina.startup.SetAllPropertiesRule begin WARNING: [SetAllPropertiesRule]{Server/Service/Connector} Setting property 'maxSpareThreads' to '50' did not find a matching property. Dec 08, 2015 12:04:00 PM org.apache.catalina.startup.SetAllPropertiesRule begin WARNING: [SetAllPropertiesRule]{Server/Service/Connector} Setting property 'maxSpareThreads' to '50' did not find a matching property. Dec 08, 2015 12:04:01 PM org.apache.tomcat.util.digester.Digester endElement WARNING:

I wrote a console application helloworld.java and ran javac helloworld.java ,and then java helloworld . This worked fine. I then created a package com.abc.project and moved helloworld.java into it(the package import statement is correctly generated which is package com.abc.project; ). And then i ran javac helloworld.java this worked also fine and generated the class properly. However, when I ran java com.abc.project.helloworld from the console, it threw an "class not found" error. Please can anyone advise what is the problem? Try running java -cp ABSOLUTE_PATH com.abc.project.helloworld Where

I have problem with running my java project. E:\Workspace\compiled>java -classpath server\libraries\log4j-1.2.16.jar;E:\Workspace\compiled\server\service-1.0-SNAPSHOT.jar;E:\Workspace\compiled\server\libraries\log4j-1.2.16.jar -Djava.security.policy=E:\Workspace\compiled\socket.policy -Djava.rmi.server.codebase=file:///E:\Workspace\compiled\server\service-1.0-SNAPSHOT.jar -jar E:\Workspace\compiled\server\service-1.0-SNAPSHOT.jar E:\Workspace\compiled\log4j.properties Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log4j/PropertyConfigurator at pwr.mgr.server.service

定义： 对于术语的定义，最原汁原味的还是官方文档。 关于 ClassNotFoundException ， JavaDoc 里这么描述： Thrown when an application tries to load in a class through its string name using: The forName method in class Class . The findSystemClass method in class ClassLoader . The loadClass method in class ClassLoader . but no definition for the class with the specified name could be found. 关于 NoClassDefFoundError ， JavaDoc 里这么描述： Thrown if the Java Virtual Machine or a ClassLoader instance tries to load in the definition of a class (as part of a normal method call or as part of creating a new instance using the new expression) and

In both client and server classes, I have an exact same inner class called Data. This Data object is being sent from the server using: ObjectOutputStream output= new ObjectOutputStream(socket.getOutputStream()); output.writeObject(d); (where d is a Data object) This object is received on the client side and cast to a Data object: ObjectInputStream input = new ObjectInputStream(socket.getInputStream()); Object receiveObject = input.readObject(); if (receiveObject instanceof Data){ Data receiveData = (Data) receiveObject; // some code here... } I'm getting a java.lang.ClassNotFoundException: