Java虚拟机的常用指令汇总（含有案例说明）

1、反编译Java class 字节码文件命令

javap -v StackStruTest.class

结果：

$ javap -v StackStruTest.class
Classfile /E:/workspace/JVMDemo/out/production/chapter01/com/rh/java/StackStruTest.class
  Last modified 2020-7-26; size 430 bytes
  MD5 checksum b1cfa494fb398acffd304335c6b4dcd4
  Compiled from "StackStruTest.java"
public class com.rh.java.StackStruTest
  minor version: 0
  major version: 52
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Methodref          #3.#19         // java/lang/Object."<init>":()V
   #2 = Class              #20            // com/rh/java/StackStruTest
   #3 = Class              #21            // java/lang/Object
   #4 = Utf8               <init>
   #5 = Utf8               ()V
   #6 = Utf8               Code
   #7 = Utf8               LineNumberTable
   #8 = Utf8               LocalVariableTable
   #9 = Utf8               this
  #10 = Utf8               Lcom/rh/java/StackStruTest;
  #11 = Utf8               main
  #12 = Utf8               ([Ljava/lang/String;)V
  #13 = Utf8               args
  #14 = Utf8               [Ljava/lang/String;
  #15 = Utf8               i
  #16 = Utf8               I
  #17 = Utf8               SourceFile
  #18 = Utf8               StackStruTest.java
  #19 = NameAndType        #4:#5          // "<init>":()V
  #20 = Utf8               com/rh/java/StackStruTest
  #21 = Utf8               java/lang/Object
{
  public com.rh.java.StackStruTest();
    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
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       5     0  this   Lcom/rh/java/StackStruTest;

  public static void main(java.lang.String[]);
    descriptor: ([Ljava/lang/String;)V
    flags: ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=2, args_size=1
         0: iconst_5
         1: istore_1
         2: return
      LineNumberTable:
        line 5: 0
        line 6: 2
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       3     0  args   [Ljava/lang/String;
            2       1     1     i   I
}
SourceFile: "StackStruTest.java"

2、查看当前Java程序中的进程命令

jps

结果：

$ jps
13456 StackStruTest
14272 Jps
14148 Launcher
4648