Java RMI Deployment

I hope that someone else has already done the suffering to learn how to do this.

I am starting to experiment with writing Java RMI client and server code. I started with the Oracle demo where the client makes a request for the value of pi to an arbitrary number of places, and the server computes it and passes it back to the client.

I was able to get this working using javac and jar from the command line (which involves bundling the class files into a JAR, copying it over to the tomcat webapps directory). My guess is that there is some way to set this up in MyEclipse so that it compiles and redeploys–but it is not exactly obvious how to set this up. Help!

I have the various components of the demo broken into three separate projects: rmi-base, rmi-client, and rmi-server. They all compile just fine.

I am using MyEclipse 9.1, Tomcat 5.0.28 (please don’t laugh; we’re working on moving into modern times, and getting rid of our papyrus and clay tablets).

To simplify figuring out what is broken, I have taken the Oracle tutorial code and put in a single project, divided into three packages: client, compute, and engine. I can start the server (engine) with the following DOS batch file:

java -cp “c:\Documents and Settings\ccramer\Workspaces\MyEclipse 9\rmi\src”;c:\tomcat5\webapps\rmi\compute.jar -Djava.rmi.server.codebase=file:/c:\tomcat5\webapps\rmi\compute.jar -Djava.security.policy=server.policy engine.ComputeEngine

Then I tried to get MyEclipse to start the server in pretty much the equivalent way using the Run Configurations…:

Main.class: engine.ComputeEngine
Classpath: default classpath and c:\tomcat5\webapps\rmi\compute.jar
Environment: java.rmi.server.codebase=file:/c:\tomcat5\webapps\rmi\compute.jar
java.security.policy=server.policy

ComputeEngine exception:
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is: 
    java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is: 
    java.lang.ClassNotFoundException: compute.Compute
    at sun.rmi.server.UnicastServerRef.oldDispatch(UnicastServerRef.java:385)
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:240)
    at sun.rmi.transport.Transport$1.run(Transport.java:153)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
    at java.lang.Thread.run(Thread.java:595)
    at sun.rmi.transport.StreamRemoteCall.exceptionReceivedFromServer(StreamRemoteCall.java:247)
    at sun.rmi.transport.StreamRemoteCall.executeCall(StreamRemoteCall.java:223)
    at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:343)
    at sun.rmi.registry.RegistryImpl_Stub.rebind(Unknown Source)
    at engine.ComputeEngine.main(ComputeEngine.java:29)
Caused by: java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is: 
    java.lang.ClassNotFoundException: compute.Compute
    at sun.rmi.registry.RegistryImpl_Skel.dispatch(Unknown Source)
    at sun.rmi.server.UnicastServerRef.oldDispatch(UnicastServerRef.java:375)
    at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:240)
    at sun.rmi.transport.Transport$1.run(Transport.java:153)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.rmi.transport.Transport.serviceCall(Transport.java:149)
    at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:460)
    at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:701)
    at java.lang.Thread.run(Thread.java:595)
Caused by: java.lang.ClassNotFoundException: compute.Compute
    at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
    at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:242)
    at sun.rmi.server.LoaderHandler.loadProxyInterfaces(LoaderHandler.java:707)
    at sun.rmi.server.LoaderHandler.loadProxyClass(LoaderHandler.java:651)
    at sun.rmi.server.LoaderHandler.loadProxyClass(LoaderHandler.java:588)
    at java.rmi.server.RMIClassLoader$2.loadProxyClass(RMIClassLoader.java:628)
    at java.rmi.server.RMIClassLoader.loadProxyClass(RMIClassLoader.java:294)
    at sun.rmi.server.MarshalInputStream.resolveProxyClass(MarshalInputStream.java:238)
    at java.io.ObjectInputStream.readProxyDesc(ObjectInputStream.java:1494)
    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1457)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1693)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:339)
    ... 9 more

As you can see, there is a ClassNotFoundException: compute.Compute

I’m hard pressed to see why. If I do a jar -tf c:\tomcat5\webapps\rmi\compute.jar I get:

META-INF/
META-INF/MANIFEST.MF
compute/Compute.class
compute/Task.class

Any suggestions?