这一次，彻底弄懂 Java 字节码文件！( 四 )_作者|东升的思考责编|Elle不啰嗦

Java字节码文件

IDEA工具编译代码后， Terminal 终端控制台，进入到生成class文件的目录下。执行如下命令： javap -verbose com .dskj.jvm.bytecode.MyTest1

生成字节码文件内容：

Classfile /.../classes/com/dskj/jvm/bytecode/MyTest.class LastmodifiedJul 31 2018 ;size 489 bytes MD5checksumbdb537edd2d216ea99d6ce529073ee42 Compiled from \"MyTest1.java\" public class com . dskj . jvm . bytecode . MyTest minorversion: 0 majorversion: 52 #JDK最大版本号 flags:ACC_PUBLICACC_SUPER Constantpool: # #1=Methodref#4.#20//java/lang/Object.\"init\":()V #2=Fieldref#3.#21//com/dskj/jvm/bytecode/MyTest1.a:I #3=Class#22//com/dskj/jvm/bytecode/MyTest1 #4=Class#23//java/lang/Object #5=Utf8a #6=Utf8I #7=Utf8init #8=Utf8()V #9=Utf8Code #10=Utf8LineNumberTable #11=Utf8LocalVariableTable #12=Utf8this #13=Utf8Lcom/dskj/jvm/bytecode/MyTest1; #14=Utf8getA #15=Utf8()I #16=Utf8setA #17=Utf8(I)V #18=Utf8SourceFile #19=Utf8MyTest1.java #20=NameAndType#7:#8//\"init\":()V #21=NameAndType#5:#6//a:I #22=Utf8com/dskj/jvm/bytecode/MyTest1 #23=Utf8java/lang/Object { publiccom.dskj.jvm.bytecode.MyTest1(); descriptor:()V flags:ACC_PUBLIC Code: stack= 2 locals= 1 args_size= 1 0 :aload_0 1 :invokespecial #1//Methodjava/lang/Object.\"init\":()V 4 :aload_0 5 :iconst_1 6 :putfield #2//Fielda:I 9 : return LineNumberTable: line 6 : 0 line 8 : 4 LocalVariableTable: StartLengthSlotNameSignature 0 10 0 this Lcom/dskj/jvm/bytecode/MyTest1; publicintgetA(); descriptor:()I flags:ACC_PUBLIC Code: stack= 1 locals= 1 args_size= 1 0 :aload_0 1 :getfield #2//Fielda:I 4 :ireturn LineNumberTable: line 11 : 0 LocalVariableTable: StartLengthSlotNameSignature 0 5 0 this Lcom/dskj/jvm/bytecode/MyTest1; publicvoidsetA(int); descriptor:(I)V flags:ACC_PUBLIC Code: stack= 2 locals= 2 args_size= 2 0 :aload_0 1 :iload_1 2 :putfield #2//Fielda:I 5 : return LineNumberTable: line 15 : 0 line 16 : 5 LocalVariableTable: StartLengthSlotNameSignature 0 6 0 this Lcom/dskj/jvm/bytecode/MyTest1; 0 6 1 aI SourceFile: \"MyTest1.java”