I get a consistent Null Pointer exception by compiling the QuoteHttpServer
file in:

/net/benden/export/home/benden0/hotjava/quoteserver/server2/

Go to that directory and run:

javac QuoteHttpServer.java

Here is the dump after the crash:

79 flar@bendenweyr :0.0> javac QuoteHttpServer.java
java.lang.NullPointerException
at java.util.Hashtable.get(Hashtable.java)
at java.tools.asm.ConstantPool.put(ConstantPool.java)
at java.tools.asm.Instruction.collect(Instruction.java)
at java.tools.asm.Assembler.collect(Assembler.java)
at java.tools.javac.SourceClass.compile(SourceClass.java:423)
at java.tools.javac.Main.main(Main.java)
-- listing --
39: aload 1
39: getfield java.lang.String file
39: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=10225125]
39: invokevirtual boolean startsWith(java.lang.String)
39: ifeq 7190344
40: aload 0
40: getfield boolean expectsMime
40: ifeq 7190416
41: aload 0
41: getfield java.io.PrintStream clientOutput
42: new class java.lang.StringBuffer
42: dup
42: invokenonvirtual java.lang.StringBuffer()
41: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=10749510]
41: invokevirtual java.lang.StringBuffer append(java.lang.String)
42: aload 0
42: invokevirtual java.lang.Class getClass()
42: invokevirtual java.lang.String getName()
42: invokevirtual java.lang.StringBuffer append(java.lang.String)
42: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=11011706]
42: invokevirtual java.lang.StringBuffer append(java.lang.String)
43: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=11273868]
43: invokevirtual java.lang.StringBuffer append(java.lang.String)
42: invokevirtual java.lang.String toString()
41: invokevirtual void print(java.lang.String)
$7190416:
45: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=11798215]
45: invokevirtual int length()
45: istore 3
46: sipush 1000
46: istore 4
47: new class java.util.Vector
47: dup
47: bipush 10
47: invokenonvirtual java.util.Vector(int)
47: astore 5
48: goto 7194920
$7194936:
49: aload 1
49: getfield java.lang.String file
49: iload 3
49: invokevirtual char charAt(int)
49: bipush 47
49: if_icmpeq 7194960
50: aload 1
50: getfield java.lang.String file
50: iload 3
50: invokevirtual char charAt(int)
50: bipush 63
50: if_icmpne 7194912
51: try 7195200
52: aload 1
52: getfield java.lang.String file
52: iload 3
52: iconst_1 1
52: iadd
52: invokevirtual java.lang.String substring(int)
52: invokestatic int parseInt(java.lang.String)
52: istore 4
$7195200:
51: goto 7194912
$7195240:
53: astore 6
54: aload 6
54: invokevirtual void printStackTrace()
51: goto 7194912
$7194960:
59: aload 1
59: getfield java.lang.String file
59: bipush 47
59: iload 3
59: iconst_1 1
59: iadd
59: invokevirtual int indexOf(int, int)
59: istore 6
60: iload 6
60: ifge 7195544
61: aload 1
61: getfield java.lang.String file
61: invokevirtual int length()
61: istore 6
$7195544:
63: aload 5
63: new class Quote
63: dup
63: aload 1
63: getfield java.lang.String file
63: iload 3
63: iconst_1 1
63: iadd
63: iload 6
63: invokevirtual java.lang.String substring(int, int)
63: invokenonvirtual Quote(java.lang.String)
63: invokevirtual void addElement(java.lang.Object)
64: iload 6
64: istore 3
$7194920:
48: aload 1
48: getfield java.lang.String file
48: invokevirtual int length()
48: iload 3
48: if_icmpgt 7194936
$7194912:
66: iconst_0 0
66: istore 6
66: goto 7195912
$7195904:
67: iconst_0 0
67: istore 7
67: goto 7196000
$7195992:
68: aload 5
68: iload 7
68: invokevirtual java.lang.Object elementAt(int)
68: checkcast class Quote
68: astore 8
69: aload 0
69: getfield java.io.PrintStream clientOutput
69: new class java.lang.StringBuffer
69: dup
69: invokenonvirtual java.lang.StringBuffer()
69: aload 8
69: getfield java.lang.String symbol
69: invokevirtual java.lang.StringBuffer append(java.lang.String)
69: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=18090357]
69: invokevirtual java.lang.StringBuffer append(java.lang.String)
69: aload 8
69: invokevirtual void getQuote()
69: invokevirtual
69: invokevirtual java.lang.String toString()
69: invokevirtual void println(java.lang.String)
67: iinc 7, 1
$7196000:
67: iload 7
67: aload 5
67: invokevirtual int size()
67: if_icmplt 7195992
71: aload 0
71: getfield java.io.PrintStream clientOutput
71: invokevirtual void flush()
72: iload 4
72: invokestatic void sleep(int)
66: iinc 6, 1
$7195912:
66: iload 6
66: ldc2 10000
66: if_icmplt 7195904
39: return
$7190344:
75: aload 1
75: getfield java.lang.String file
75: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=19663327]
75: invokevirtual boolean equals(java.lang.Object)
75: ifeq 7196496
76: aload 0
76: new class net.www.html.URL
76: dup
76: aload 1
76: ldc2 java/tools/tree/Node.java/tools/tree/Expression.java/tools/tree/ConstantExpression.java/tools/tree/StringExpression[value=java/lang/String, type=java/tools/java/Type.java/tools/java/ClassType, op=69, where=19925522]
76: invokenonvirtual net.www.html.URL(net.www.html.URL,java.lang.String)
76: aload 2
76: invokenonvirtual void getRequest(net.www.html.URL, java.lang.String)
75: return
$7196496:
79: aload 0
79: aload 1
79: aload 2
79: invokenonvirtual void getRequest(net.www.html.URL, java.lang.String)
38: return
java.lang.NullPointerException
at java.tools.asm.ConstantPool.index(ConstantPool.java)
at java.tools.javac.SourceClass.compile(SourceClass.java:490)
at java.tools.javac.Main.main(Main.java)
javac: An exception has occurred in the compiler, please file a bug report.
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
at java.tools.javac.BatchEnvironment.flushErrors(BatchEnvironment.java)
at java.tools.javac.Main.main(Main.java)


Here is a very small test case that causes an exception in the interpreter:

-------test.java--------

class test {
    native void foo();

    public test() {
System.out.println("This should be a void: " + foo());
    }
}

------------------------