54 lines
1.9 KiB
Java
54 lines
1.9 KiB
Java
package bcelifier;
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import org.apache.commons.bcel6.generic.*;
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import org.apache.commons.bcel6.classfile.*;
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import org.apache.commons.bcel6.*;
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import java.io.*;
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public class NullCreator implements Constants {
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private InstructionFactory _factory;
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private ConstantPoolGen _cp;
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private ClassGen _cg;
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public NullCreator() {
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_cg = new ClassGen("bcelifier.Null", "java.lang.Object", "Null.java", ACC_PUBLIC | ACC_SUPER, new String[] { });
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_cp = _cg.getConstantPool();
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_factory = new InstructionFactory(_cg, _cp);
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}
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public void create(OutputStream out) throws IOException {
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createFields();
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createMethod_0();
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_cg.getJavaClass().dump(out);
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}
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private void createFields() {
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FieldGen field;
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field = new FieldGen(0, new ObjectType("java.lang.Integer"), "i", _cp);
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_cg.addField(field.getField());
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}
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private void createMethod_0() {
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InstructionList il = new InstructionList();
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MethodGen method = new MethodGen(ACC_PUBLIC, Type.VOID, Type.NO_ARGS, new String[] { }, "<init>", "bcelifier.Null", il, _cp);
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InstructionHandle ih_0 = il.append(_factory.createLoad(Type.OBJECT, 0));
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il.append(_factory.createInvoke("java.lang.Object", "<init>", Type.VOID, Type.NO_ARGS, Constants.INVOKESPECIAL));
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InstructionHandle ih_4 = il.append(_factory.createLoad(Type.OBJECT, 0));
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il.append(InstructionConstants.ACONST_NULL);
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il.append(_factory.createFieldAccess("bcelifier.Null", "i", new ObjectType("java.lang.Integer"), Constants.PUTFIELD));
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InstructionHandle ih_9 = il.append(_factory.createReturn(Type.VOID));
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method.setMaxStack();
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method.setMaxLocals();
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_cg.addMethod(method.getMethod());
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il.dispose();
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}
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public static void main(String[] args) throws Exception {
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bcelifier.NullCreator creator = new bcelifier.NullCreator();
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creator.create(new FileOutputStream("bcelifier.Null.class"));
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}
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}
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