package com.zarbosoft.semicompiled;
class Main {
public static void myMain(int x) {
int y;
switch (x) {
case 0:
y = 0;
break;
case 1:
y = 33;
break;
default:
y = 72;
break;
}
}
}
Classfile /tmp/semicompiled-Pt6uIbVR-17320156677467552979/com/zarbosoft/semicompiled/Main.class
Last modified Jun 2, 2024; size 296 bytes
MD5 checksum cc334ede0a635dd59edc40cd7d5cc090
class com.zarbosoft.semicompiled.Main
minor version: 0
major version: 52
flags: (0x0020) ACC_SUPER
this_class: #2 // com/zarbosoft/semicompiled/Main
super_class: #3 // java/lang/Object
interfaces: 0, fields: 0, methods: 2, attributes: 0
Constant pool:
#1 = Methodref #3.#12 // java/lang/Object."<init>":()V
#2 = Class #13 // com/zarbosoft/semicompiled/Main
#3 = Class #14 // java/lang/Object
#4 = Utf8 <init>
#5 = Utf8 ()V
#6 = Utf8 Code
#7 = Utf8 myMain
#8 = Utf8 (I)V
#9 = Utf8 StackMapTable
#10 = Utf8 MethodParameters
#11 = Utf8 x
#12 = NameAndType #4:#5 // "<init>":()V
#13 = Utf8 com/zarbosoft/semicompiled/Main
#14 = Utf8 java/lang/Object
{
com.zarbosoft.semicompiled.Main();
descriptor: ()V
flags: (0x0000)
Code:
stack=1, locals=1, args_size=1
0: aload_0
1: invokespecial #1 // Method java/lang/Object."<init>":()V
4: return
public static void myMain(int);
descriptor: (I)V
flags: (0x0009) ACC_PUBLIC, ACC_STATIC
Code:
stack=1, locals=2, args_size=1
0: iload_0
1: lookupswitch { // 2
0: 28
1: 33
default: 39
}
28: iconst_0
29: istore_1
30: goto 42
33: bipush 33
35: istore_1
36: goto 42
39: bipush 72
41: istore_1
42: return
StackMapTable: number_of_entries = 4
frame_type = 28 /* same */
frame_type = 4 /* same */
frame_type = 5 /* same */
frame_type = 252 /* append */
offset_delta = 2
locals = [ int ]
MethodParameters:
Name Flags
x
}
package asm.com.zarbosoft.semicompiled;
import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.ConstantDynamic;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.RecordComponentVisitor;
import org.objectweb.asm.Type;
import org.objectweb.asm.TypePath;
public class MainDump implements Opcodes {
public static byte[] dump() throws Exception {
ClassWriter classWriter = new ClassWriter(0);
FieldVisitor fieldVisitor;
RecordComponentVisitor recordComponentVisitor;
MethodVisitor methodVisitor;
AnnotationVisitor annotationVisitor0;
classWriter.visit(
V1_8, ACC_SUPER, "com/zarbosoft/semicompiled/Main", null, "java/lang/Object", null);
{
methodVisitor = classWriter.visitMethod(0, "<init>", "()V", null, null);
methodVisitor.visitCode();
methodVisitor.visitVarInsn(ALOAD, 0);
methodVisitor.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
methodVisitor.visitInsn(RETURN);
methodVisitor.visitMaxs(1, 1);
methodVisitor.visitEnd();
}
{
methodVisitor =
classWriter.visitMethod(ACC_PUBLIC | ACC_STATIC, "myMain", "(I)V", null, null);
methodVisitor.visitParameter("x", 0);
methodVisitor.visitCode();
methodVisitor.visitVarInsn(ILOAD, 0);
Label label0 = new Label();
Label label1 = new Label();
Label label2 = new Label();
methodVisitor.visitLookupSwitchInsn(label2, new int[] {0, 1}, new Label[] {label0, label1});
methodVisitor.visitLabel(label0);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitInsn(ICONST_0);
methodVisitor.visitVarInsn(ISTORE, 1);
Label label3 = new Label();
methodVisitor.visitJumpInsn(GOTO, label3);
methodVisitor.visitLabel(label1);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitIntInsn(BIPUSH, 33);
methodVisitor.visitVarInsn(ISTORE, 1);
methodVisitor.visitJumpInsn(GOTO, label3);
methodVisitor.visitLabel(label2);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitIntInsn(BIPUSH, 72);
methodVisitor.visitVarInsn(ISTORE, 1);
methodVisitor.visitLabel(label3);
methodVisitor.visitFrame(Opcodes.F_APPEND, 1, new Object[] {Opcodes.INTEGER}, 0, null);
methodVisitor.visitInsn(RETURN);
methodVisitor.visitMaxs(1, 2);
methodVisitor.visitEnd();
}
classWriter.visitEnd();
return classWriter.toByteArray();
}
}
Classfile /tmp/semicompiled-Pt6uIbVR-17320156677467552979/com/zarbosoft/semicompiled/Main.class
Last modified Jun 2, 2024; size 513 bytes
MD5 checksum 13b2bc30239a2e970fa40399bf4ee95d
Compiled from "Main.java"
class com.zarbosoft.semicompiled.Main
minor version: 0
major version: 52
flags: (0x0020) ACC_SUPER
this_class: #2 // com/zarbosoft/semicompiled/Main
super_class: #3 // java/lang/Object
interfaces: 0, fields: 0, methods: 2, attributes: 1
Constant pool:
#1 = Methodref #3.#20 // java/lang/Object."<init>":()V
#2 = Class #21 // com/zarbosoft/semicompiled/Main
#3 = Class #22 // java/lang/Object
#4 = Utf8 <init>
#5 = Utf8 ()V
#6 = Utf8 Code
#7 = Utf8 LineNumberTable
#8 = Utf8 LocalVariableTable
#9 = Utf8 this
#10 = Utf8 Lcom/zarbosoft/semicompiled/Main;
#11 = Utf8 myMain
#12 = Utf8 (I)V
#13 = Utf8 y
#14 = Utf8 I
#15 = Utf8 x
#16 = Utf8 StackMapTable
#17 = Utf8 MethodParameters
#18 = Utf8 SourceFile
#19 = Utf8 Main.java
#20 = NameAndType #4:#5 // "<init>":()V
#21 = Utf8 com/zarbosoft/semicompiled/Main
#22 = Utf8 java/lang/Object
{
com.zarbosoft.semicompiled.Main();
descriptor: ()V
flags: (0x0000)
Code:
stack=1, locals=1, args_size=1
0: aload_0
1: invokespecial #1 // Method java/lang/Object."<init>":()V
4: return
LineNumberTable:
line 3: 0
LocalVariableTable:
Start Length Slot Name Signature
0 5 0 this Lcom/zarbosoft/semicompiled/Main;
public static void myMain(int);
descriptor: (I)V
flags: (0x0009) ACC_PUBLIC, ACC_STATIC
Code:
stack=1, locals=2, args_size=1
0: iload_0
1: lookupswitch { // 2
0: 28
1: 33
default: 39
}
28: iconst_0
29: istore_1
30: goto 42
33: bipush 33
35: istore_1
36: goto 42
39: bipush 72
41: istore_1
42: return
LineNumberTable:
line 5: 0
line 6: 42
LocalVariableTable:
Start Length Slot Name Signature
30 3 1 y I
36 3 1 y I
0 43 0 x I
42 1 1 y I
StackMapTable: number_of_entries = 4
frame_type = 28 /* same */
frame_type = 4 /* same */
frame_type = 5 /* same */
frame_type = 252 /* append */
offset_delta = 2
locals = [ int ]
MethodParameters:
Name Flags
x
}
SourceFile: "Main.java"
package asm.com.zarbosoft.semicompiled;
import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Attribute;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.ConstantDynamic;
import org.objectweb.asm.FieldVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.RecordComponentVisitor;
import org.objectweb.asm.Type;
import org.objectweb.asm.TypePath;
public class MainDump implements Opcodes {
public static byte[] dump() throws Exception {
ClassWriter classWriter = new ClassWriter(0);
FieldVisitor fieldVisitor;
RecordComponentVisitor recordComponentVisitor;
MethodVisitor methodVisitor;
AnnotationVisitor annotationVisitor0;
classWriter.visit(
V1_8, ACC_SUPER, "com/zarbosoft/semicompiled/Main", null, "java/lang/Object", null);
classWriter.visitSource("Main.java", null);
{
methodVisitor = classWriter.visitMethod(0, "<init>", "()V", null, null);
methodVisitor.visitCode();
Label label0 = new Label();
methodVisitor.visitLabel(label0);
methodVisitor.visitLineNumber(3, label0);
methodVisitor.visitVarInsn(ALOAD, 0);
methodVisitor.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V", false);
methodVisitor.visitInsn(RETURN);
Label label1 = new Label();
methodVisitor.visitLabel(label1);
methodVisitor.visitLocalVariable(
"this", "Lcom/zarbosoft/semicompiled/Main;", null, label0, label1, 0);
methodVisitor.visitMaxs(1, 1);
methodVisitor.visitEnd();
}
{
methodVisitor =
classWriter.visitMethod(ACC_PUBLIC | ACC_STATIC, "myMain", "(I)V", null, null);
methodVisitor.visitParameter("x", 0);
methodVisitor.visitCode();
Label label0 = new Label();
methodVisitor.visitLabel(label0);
methodVisitor.visitLineNumber(5, label0);
methodVisitor.visitVarInsn(ILOAD, 0);
Label label1 = new Label();
Label label2 = new Label();
Label label3 = new Label();
methodVisitor.visitLookupSwitchInsn(label3, new int[] {0, 1}, new Label[] {label1, label2});
methodVisitor.visitLabel(label1);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitInsn(ICONST_0);
methodVisitor.visitVarInsn(ISTORE, 1);
Label label4 = new Label();
methodVisitor.visitLabel(label4);
Label label5 = new Label();
methodVisitor.visitJumpInsn(GOTO, label5);
methodVisitor.visitLabel(label2);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitIntInsn(BIPUSH, 33);
methodVisitor.visitVarInsn(ISTORE, 1);
Label label6 = new Label();
methodVisitor.visitLabel(label6);
methodVisitor.visitJumpInsn(GOTO, label5);
methodVisitor.visitLabel(label3);
methodVisitor.visitFrame(Opcodes.F_SAME, 0, null, 0, null);
methodVisitor.visitIntInsn(BIPUSH, 72);
methodVisitor.visitVarInsn(ISTORE, 1);
methodVisitor.visitLabel(label5);
methodVisitor.visitLineNumber(6, label5);
methodVisitor.visitFrame(Opcodes.F_APPEND, 1, new Object[] {Opcodes.INTEGER}, 0, null);
methodVisitor.visitInsn(RETURN);
Label label7 = new Label();
methodVisitor.visitLabel(label7);
methodVisitor.visitLocalVariable("y", "I", null, label4, label2, 1);
methodVisitor.visitLocalVariable("y", "I", null, label6, label3, 1);
methodVisitor.visitLocalVariable("x", "I", null, label0, label7, 0);
methodVisitor.visitLocalVariable("y", "I", null, label5, label7, 1);
methodVisitor.visitMaxs(1, 2);
methodVisitor.visitEnd();
}
classWriter.visitEnd();
return classWriter.toByteArray();
}
}
Join the thriving social scene at github.com/andrewbaxter/semicompiled.