com.github.wolf480pl.mias4j.MakeTestMH.java Source code

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Here is the source code for com.github.wolf480pl.mias4j.MakeTestMH.java

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/*
 * Copyright (c) 2014 Wolf480pl <wolf480@interia.pl>
 * This program is licensed under the GNU Lesser General Public License.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.github.wolf480pl.mias4j;

import java.io.FileOutputStream;

import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

public class MakeTestMH implements Opcodes {

    public static byte[] dump() throws Exception {

        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES | ClassWriter.COMPUTE_MAXS);
        MethodVisitor mv;

        cw.visit(V1_7, ACC_PUBLIC + ACC_SUPER, "TestMH", null, "java/lang/Object", null);

        cw.visitInnerClass("java/lang/invoke/MethodHandles$Lookup", "java/lang/invoke/MethodHandles", "Lookup",
                ACC_PUBLIC + ACC_FINAL + ACC_STATIC);

        {
            mv = cw.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
            mv.visitCode();
            mv.visitVarInsn(ALOAD, 0);
            mv.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
            mv.visitInsn(RETURN);
            mv.visitMaxs(1, 1);
            mv.visitEnd();
        }
        {
            mv = cw.visitMethod(ACC_PUBLIC + ACC_STATIC, "main", "([Ljava/lang/String;)V", null, null);
            mv.visitCode();
            Label l0 = new Label();
            Label l1 = new Label();
            Label l2 = new Label();
            mv.visitTryCatchBlock(l0, l1, l2, "java/lang/Throwable");
            mv.visitLabel(l0);
            /*mv.visitMethodInsn(INVOKESTATIC, "java/lang/invoke/MethodHandles", "lookup", "()Ljava/lang/invoke/MethodHandles$Lookup;", false);
            mv.visitLdcInsn(Type.getType("Ljava/io/PrintStream;"));
            mv.visitLdcInsn("println");
            mv.visitFieldInsn(GETSTATIC, "java/lang/Void", "TYPE", "Ljava/lang/Class;");
            mv.visitLdcInsn(Type.getType("Ljava/lang/String;"));
            mv.visitMethodInsn(INVOKESTATIC, "java/lang/invoke/MethodType", "methodType", "(Ljava/lang/Class;Ljava/lang/Class;)Ljava/lang/invoke/MethodType;", false);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandles$Lookup", "findVirtual", "(Ljava/lang/Class;Ljava/lang/String;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/MethodHandle;", false);*/
            mv.visitLdcInsn(new Handle(H_INVOKEVIRTUAL, "java/io/PrintStream", "println",
                    Type.getMethodDescriptor(Type.VOID_TYPE, Type.getType(String.class))));
            mv.visitVarInsn(ASTORE, 1);
            mv.visitVarInsn(ALOAD, 1);
            mv.visitFieldInsn(GETSTATIC, "java/lang/System", "out", "Ljava/io/PrintStream;");
            mv.visitLdcInsn("hey");
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/invoke/MethodHandle", "invoke",
                    "(Ljava/io/PrintStream;Ljava/lang/String;)V", false);
            mv.visitLabel(l1);
            Label l3 = new Label();
            mv.visitJumpInsn(GOTO, l3);
            mv.visitLabel(l2);
            mv.visitFrame(Opcodes.F_SAME1, 0, null, 1, new Object[] { "java/lang/Throwable" });
            mv.visitVarInsn(ASTORE, 1);
            mv.visitVarInsn(ALOAD, 1);
            mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Throwable", "printStackTrace", "()V", false);
            mv.visitLabel(l3);
            mv.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
            mv.visitInsn(RETURN);
            mv.visitMaxs(5, 2);
            mv.visitEnd();
        }
        cw.visitEnd();

        return cw.toByteArray();
    }

    public static void main(String[] args) throws Exception {
        FileOutputStream os = new FileOutputStream(args[0]);
        os.write(dump());
        os.flush();
        os.close();
    }
}