javap的简单使用

  1. 编写一个Java源代码文件
package org.fenixsoft.clazz;

public class TestClass {

    private int m;

    public int inc() {
        return m + 1;
    }
}
  1. 使用javac进行编译得到Class文件
    javap的简单使用
  2. 使用javap进行反编译
    javap的简单使用
  3. 结果展示
public class org.fenixsoft.clazz.TestClass
  minor version: 0
  major version: 52
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Methodref          #4.#15         // java/lang/Object."<init>":()V
   #2 = Fieldref           #3.#16         // org/fenixsoft/clazz/TestClass.m:I
   #3 = Class              #17            // org/fenixsoft/clazz/TestClass
   #4 = Class              #18            // java/lang/Object
   #5 = Utf8               m
   #6 = Utf8               I
   #7 = Utf8               <init>
   #8 = Utf8               ()V
   #9 = Utf8               Code
  #10 = Utf8               LineNumberTable
  #11 = Utf8               inc
  #12 = Utf8               ()I
  #13 = Utf8               SourceFile
  #14 = Utf8               TestClass.java
  #15 = NameAndType        #7:#8          // "<init>":()V
  #16 = NameAndType        #5:#6          // m:I
  #17 = Utf8               org/fenixsoft/clazz/TestClass
  #18 = Utf8               java/lang/Object
{
  public org.fenixsoft.clazz.TestClass();
    descriptor: ()V
    flags: ACC_PUBLIC
    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

  public int inc();
    descriptor: ()I
    flags: ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
         0: aload_0
         1: getfield      #2                  // Field m:I
         4: iconst_1
         5: iadd
         6: ireturn
      LineNumberTable:
        line 8: 0
}
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