"Inline assembly" for Java byte codes

Question

I'm looking for existing implementations of the following idea: suppose somebody wants to write "inline assembly" byte codes inside a normal Java program (most relevant applications would involve invokedynamic instruction that is not otherwise available in Java). One way to do this would be as follows:

void foo(boolean b) {
    Label l1 = Asm.label();
    Label l2 = Asm.label();

    int i = Asm.no_int();
    Asm._const(0);
    Asm.store(i);
    l1.bind();
    Asm.load(i);
    Asm.push(10);
    Asm.if_cmpge(l2);
    Asm.getstatic("java/lang/System", "out", "Ljava/io/PrintStream");
    Asm.load(i);
    Asm.invokevirtual("java/io/PrintStream", "println", "(I)V");
    Asm.inc(i);
    Asm._goto(l1);
    l2.bind();
    Asm._return();
}

Instructions are encoded as API calls, then we'd need to run a normal java compiler, and then to post-process the byte code and replace the API calls with actual instructions.

P.S. I'm aware of ASMifier of the ASM Framework, it does not solve the problem stated above.

Answer 1

ClassLoader has a method, defineClass, that lets you dynamically generate a class by providing the bytecode. Combine this with Javassist or other suggestions from this previous question.