How can I remove some opcodes from Java class file?

Asked Jun 17 '12 at 10:40

Active Jun 17 '12 at 11:26

Viewed 285 times

Here are some code lines:

//   43: invokevirtual 10   test/main:a (I)test/sub1;
//   46: pop
//   47: goto +4 -> 51
//   50: athrow
//   51: aload_2

This is the byte code of a sample Java class file.

I want to remove the opcodes of lines 47, 50... from java class file.

How can I do this using ASM?

edited Jun 17 '12 at 11:26

Mat

asked Jun 17 '12 at 10:40

SkyDragon

2

What do you mean by "remove"? What is the aim here? – Oliver Charlesworth Jun 17 '12 at 12:43
I want // 43: invokevirtual 10 test/main:a (I)test/sub1; // 46: pop // 47: alod_2 after change java class file... – SkyDragon Jun 17 '12 at 15:20
If I remove them using CCk(Class Construction Kit), then OK. But if I remove them using ASM, then errors throws... – SkyDragon Jun 17 '12 at 15:23
1

But **why** do you want/need to do this? What problem are you trying to solve? – Oliver Charlesworth Jun 17 '12 at 15:28
I want to do this for decompiling programmatically – SkyDragon Jun 18 '12 at 00:31
@SkyDragon, most likely the reason you're getting errors is because simply removing the instructions means that the stack and locals now have invalid types. If you explain what you're actually trying to do, I might be able to help you come up with a better solution. – Antimony Mar 30 '13 at 21:19

0 Answers0