java.lang.VerifyError: Bad type on operand stack in method com.sun.net.httpserver.spi.HttpServerProvider

Question

I have been plagued by this problem and managed to narrow it down to a small file that fails throwing the java.lang.VerifyError when invoked from Ant with fork set to false in the <java> task but succeeds when fork is set to true.

The self-contained file is:

package foo;

import javax.xml.ws.Endpoint;

import javax.jws.WebService;

@WebService
class Hello  {
    public String sayHello() {
        return "hello";
    }
}


public class FooMain {
    public static void main(String args[]) throws Exception {
        Object implementor = new Hello();
        String address = "http://localhost:9000/SoapContext/SoapPort";
        Endpoint.publish(address, implementor);
    }
}

When invoked with Ant and fork set to false it throws:

 [java] java.lang.VerifyError: Bad type on operand stack
 [java] Exception Details:
 [java]   Location:
 [java]     com/sun/net/httpserver/spi/HttpServerProvider$1.run()Ljava/lang/Object; @27: invokestatic
 [java]   Reason:
 [java]     Type 'sun/net/httpserver/DefaultHttpServerProvider' (current frame, stack[0]) is not assignable to 'com/sun/net/httpserver/spi/HttpServerProvider'
 [java]   Current Frame:
 [java]     bci: @27
 [java]     flags: { }
 [java]     locals: { 'com/sun/net/httpserver/spi/HttpServerProvider$1' }
 [java]     stack: { 'sun/net/httpserver/DefaultHttpServerProvider' }
 [java]   Bytecode:
 [java]     0000000: b800 2599 0007 b800 27b0 b800 2699 0007
 [java]     0000010: b800 27b0 bb00 1a59 b700 2ab8 0028 57b8
 [java]     0000020: 0027 b0                                
 [java]   Stackmap Table:
 [java]     same_frame(@10)

When invoked with fork set to true it succeeds. The specific exception VerifyError especially when combined with "Bad type on operand stack" points to a compiler bug from what I've read but why should it succeed or fail depending on the fork attribute of the <java> Ant task is beyond me. Any thoughts? I am running Ubuntu 12.04 with the following java tools:

$ java -version
java version "1.7.0_40"
Java(TM) SE Runtime Environment (build 1.7.0_40-b43)
Java HotSpot(TM) Server VM (build 24.0-b56, mixed mode)
$ javac -version
javac 1.7.0_40
$ ant -version
Apache Ant(TM) version 1.8.2 compiled on December 3 2011
$ ant -diagnostics | grep java.vm
java.vm.version : 24.0-b56
java.vm.vendor : Oracle Corporation
java.vm.name : Java HotSpot(TM) Server VM
java.vm.specification.name : Java Virtual Machine Specification
java.vm.specification.vendor : Oracle Corporation
java.vm.specification.version : 1.7
java.vm.info : mixed mode

important update

When invoked from Ant with fork set to false I also have to explicitly add /usr/lib/jvm/jdk1.7.0/jre/lib/rt.jar to the CLASSPATH in order to trigger the VerifyError exception. Otherwise it fails before reaching that point with:

javax.xml.ws.WebServiceException: Provider com.sun.xml.internal.ws.spi.ProviderImpl not found

Of course having to add rt.jar in the CLASSPATH is mighty strange especially since it is the rt.jar of the java version I am using.

Answer 1

This is most likely due to the mismatch between java versions, I see you are running 1.7.0_40 and 1.7.0_24. Ensure JAVA_HOME is set to the 1.7.0_40 JDK prior to invoking Ant. See the following post for additional information on how to do that. How do I change the JAVA_HOME for ant?

Answer 2

Well, most likely, it just is a compiler bug, see http://bugs.java.com/bugdatabase/view_bug.do?bug_id=8006684

And it does not really depend on the fork property as per your description, only the classpath does.