程式碼：

1 public class AppGo{
2  public static void test() {
3   boolean flag = true;
4   if (flag) System.out.println("Hello, Java!");
5   if (flag == true) System.out.println("Hello, JVM!");
6  }
7 }

javac -g AppGo.java

javap -p -v AppGo.class

Classfile /code/asmtoolsTest/AppGo.class
  Last modified 
 
2020-11-16; size 549 bytes
  MD5 checksum 080f0b86a8d6f3f00b616181e3b05973
  Compiled from "AppGo.java"
public class AppGo
  minor version: 0
  major version: 52
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Methodref          #7.#21         // java/lang/Object."<init>":()V
   #2 = Fieldref           #22.#23        //
 
 java/lang/System.out:Ljava/io/PrintStream;
   #3 = String             #24            // Hello, Java!
   #4 = Methodref          #25.#26        // java/io/PrintStream.println:(Ljava/lang/String;)V
   #5 = String             #27            // Hello, JVM!
   #6 = Class              #28            // AppGo
   #7 = Class              #29            //
 
 java/lang/Object
   #8 = Utf8               <init>
   #9 = Utf8               ()V
  #10 = Utf8               Code
  #11 = Utf8               LineNumberTable
  #12 = Utf8               LocalVariableTable
  #13 = Utf8               this
  #14 = Utf8               LAppGo;
  #15 = Utf8               test
  #16 = Utf8               flag
  #17 = Utf8               Z
  #18 = Utf8               StackMapTable
  #19 = Utf8               SourceFile
  #20 = Utf8               AppGo.java
  #21 = NameAndType        #8:#9          // "<init>":()V
  #22 = Class              #30            // java/lang/System
  #23 = NameAndType        #31:#32        // out:Ljava/io/PrintStream;
  #24 = Utf8               Hello, Java!
  #25 = Class              #33            // java/io/PrintStream
  #26 = NameAndType        #34:#35        // println:(Ljava/lang/String;)V
  #27 = Utf8               Hello, JVM!
  #28 = Utf8               AppGo
  #29 = Utf8               java/lang/Object
  #30 = Utf8               java/lang/System
  #31 = Utf8               out
  #32 = Utf8               Ljava/io/PrintStream;
  #33 = Utf8               java/io/PrintStream
  #34 = Utf8               println
  #35 = Utf8               (Ljava/lang/String;)V
{
  public AppGo();
    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 2: 0
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            0       5     0  this   LAppGo;

  public static void test();
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_STATIC                                                           區域性變量表      運算元棧
    Code:
      stack=2, locals=1, args_size=0 
         0: iconst_1                             //    將int型值1入運算元棧                     null            1
         1: istore_0                          // 從運算元棧頂出棧一個int型值存入區域性變數0號位置      1              null
         2: iload_0                           //  從區域性變數0號位置載入一個int型值入運算元棧         1               1
         3: ifeq          14        // 從運算元棧出棧1個數，跟0比較（ifeq），相等則跳過if後面的語句    1              null
         6: getstatic     #2   // Field java/lang/System.out:Ljava/io/PrintStream;          
         9: ldc           #3   // String Hello, Java!
        11: invokevirtual #4   // Method java/io/PrintStream.println:(Ljava/lang/String;)V
        14: iload_0            // 從區域性變數0號位置載入一個int型值入運算元棧                        1                1
        15: iconst_1           // 將int型值1入運算元棧                                          1                1， 1
        16: if_icmpne     27   // 從運算元棧棧頂出2個int，如果不相等（if_icmpne），則跳過if後面的語句  1               null
        19: getstatic     #2  // Field java/lang/System.out:Ljava/io/PrintStream;
        22: ldc           #5  // String Hello, JVM!
        24: invokevirtual #4  // Method java/io/PrintStream.println:(Ljava/lang/String;)V
        27: return
      LineNumberTable:
        line 4: 0
        line 5: 2
        line 6: 14
        line 7: 27
      LocalVariableTable:
        Start  Length  Slot  Name   Signature
            2      26     0  flag   Z
      StackMapTable: number_of_entries = 2
        frame_type = 252 /* append */
          offset_delta = 14
          locals = [ int ]
        frame_type = 12 /* same */
}
SourceFile: "AppGo.java"