《The JVM Specification》- ch4 The class File Format
there is nothing but a map for class file format
an example
public class Main {
public static void main(String[] args) {
// write your code here
int a = 1;
int b = 2;
int c = a + b;
}
}
to class file
macbook:src bblu$ javac Main.java
macbook:src bblu$ ls
Main.class Main.java cn
macbook:src bblu$ javap -v Main.class
Classfile /Users/bblu/IdeaProjects/Test/src/Main.class
Last modified Jul 3, 2018; size 273 bytes
MD5 checksum a3ecac22d2e8975b9bf21afa4ff0502b
Compiled from "Main.java"
public class Main
minor version: 0
major version: 52
flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
#1 = Methodref #3.#12 // java/lang/Object."<init>":()V
#2 = Class #13 // Main
#3 = Class #14 // java/lang/Object
#4 = Utf8 <init>
#5 = Utf8 ()V
#6 = Utf8 Code
#7 = Utf8 LineNumberTable
#8 = Utf8 main
#9 = Utf8 ([Ljava/lang/String;)V
#10 = Utf8 SourceFile
#11 = Utf8 Main.java
#12 = NameAndType #4:#5 // "<init>":()V
#13 = Utf8 Main
#14 = Utf8 java/lang/Object
{
public Main();
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 1: 0
public static void main(java.lang.String[]);
descriptor: ([Ljava/lang/String;)V
flags: ACC_PUBLIC, ACC_STATIC
Code:
stack=2, locals=4, args_size=1
0: iconst_1
1: istore_1
2: iconst_2
3: istore_2
4: iload_1
5: iload_2
6: iadd
7: istore_3
8: return
LineNumberTable:
line 5: 0
line 6: 2
line 7: 4
line 8: 8
}
SourceFile: "Main.java"
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