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BCEL code example to put "new Class[]{String.class}" on the stack

I am looking for a BCEL code example on how to create an array of size 1 containing instances of java.lang.Class and initialize its only element with a reference to java.lang.String.class

in other terms, I am looking for a BCEL code sample to put "new Class[]{String.class}" on the stack.

Thanks.

Solution

  • Assuming that you want to create a class file version 49 (Java 5) or higher, the required instruction sequence is:

    iconst_1
    anewarrayjava/lang/Class
    dup
    iconst_0
    ldcjava.lang.String.class
    aastore

    Now the only question left is how to generate that in BCEL. According to what I saw from its website, the generator code may look like this:

    il.append(InstructionConstants.ICONST_1);
il.append(factory.createNewArray(Type.getType(Class.class), 1));
il.append(InstructionConstants.DUP);
il.append(InstructionConstants.ICONST_0);
il.append(new LDC(constantPoolGen.addClass(Type.getType(String.class))));
il.append(InstructionConstants.AASTORE);

    Though I haven’t tested it.