JVM INSTR pop;????????

[yangyuex]

Hi,

Who can tell me what's mean of

"JVM INSTR pop; " in my  attatched file.

When I compiler the attatched file,
the compiler complains that it does not support
"goto", so I decided to understand this small program that
I can rewrite it.


Thanks very much!
Yangyuexiang


    public boolean isTree()
    {
        boolean flag;
        String s;
        Enumeration enumeration;
        flag = true;
        if(this instanceof Tree)
            return true;
        s = defUniqueSystemKey(null, false);
        enumeration = enumerateVertices();
          goto _L1
_L4:
        Vertex vertex = (Vertex)enumeration.nextElement();
          goto _L2
        JVM INSTR pop ;
        continue; /* Loop/switch isn't completed */
_L2:
        if(vertex.systemdict.getBoolean(s) || _isTreeBranch(vertex, s))
            continue; /* Loop/switch isn't completed */
        flag = false;
        break; /* Loop/switch isn't completed */
_L1:
        if(enumeration.hasMoreElements()) goto _L4; else goto _L3
_L3:
        undefSystemKey(s);

        return flag;
    }