Java注解实现浅析https://blog.csdn.net/kisimple/article/details/43709505
Java字节码（.class文件）格式详解https://www.xuebuyuan.com/1778079.html
java注解——最通俗易懂的解释https://zhuanlan.zhihu.com/p/41554884
Java奇技淫巧-插件化注解处理API(Pluggable Annotation Processing API)https://www.cnblogs.com/throwable/p/9139908.html
TestMain
import java.io.IOException;
@TestAnnotation(count = 0x7fffffff)
public class TestMain {
public static void main(String[] args) throws InterruptedException, NoSuchFieldException, IllegalAccessException, IOException{
TestAnnotation annotation = TestMain.class.getAnnotation(TestAnnotation.class);
System.out.println(annotation.count());
System.in.read();
}
}
TestAnnotation
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
/**
* Created by Administrator on 2015/1/18.
*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface TestAnnotation {
int count() default 1;
}
TestMain 反编译
javap -v TestMain.class
Classfile /Users/yanglihua/Desktop/temp/TestMain.class
Last modified May 15, 2019; size 877 bytes
MD5 checksum fdee1cc47020ac40a5f89847c88a9e64
Compiled from "TestMain.java"
public class TestMain
minor version: 0
major version: 52
flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
#1 = Methodref #10.#28 // java/lang/Object."<init>":()V
#2 = Class #29 // TestMain
#3 = Class #30 // TestAnnotation
#4 = Methodref #31.#32 // java/lang/Class.getAnnotation:(Ljava/lang/Class;)Ljava/lang/annotation/Annotation;
#5 = Fieldref #33.#34 // java/lang/System.out:Ljava/io/PrintStream;
#6 = InterfaceMethodref #3.#35 // TestAnnotation.count:()I
#7 = Methodref #36.#37 // java/io/PrintStream.println:(I)V
#8 = Fieldref #33.#38 // java/lang/System.in:Ljava/io/InputStream;
#9 = Methodref #39.#40 // java/io/InputStream.read:()I
#10 = Class #41 // java/lang/Object
#11 = Utf8 <init>
#12 = Utf8 ()V
#13 = Utf8 Code
#14 = Utf8 LineNumberTable
#15 = Utf8 main
#16 = Utf8 ([Ljava/lang/String;)V
#17 = Utf8 Exceptions
#18 = Class #42 // java/lang/InterruptedException
#19 = Class #43 // java/lang/NoSuchFieldException
#20 = Class #44 // java/lang/IllegalAccessException
#21 = Class #45 // java/io/IOException
#22 = Utf8 SourceFile
#23 = Utf8 TestMain.java
#24 = Utf8 RuntimeVisibleAnnotations
#25 = Utf8 LTestAnnotation;
#26 = Utf8 count
#27 = Integer 2147483647
#28 = NameAndType #11:#12 // "<init>":()V
#29 = Utf8 TestMain
#30 = Utf8 TestAnnotation
#31 = Class #46 // java/lang/Class
#32 = NameAndType #47:#48 // getAnnotation:(Ljava/lang/Class;)Ljava/lang/annotation/Annotation;
#33 = Class #49 // java/lang/System
#34 = NameAndType #50:#51 // out:Ljava/io/PrintStream;
#35 = NameAndType #26:#52 // count:()I
#36 = Class #53 // java/io/PrintStream
#37 = NameAndType #54:#55 // println:(I)V
#38 = NameAndType #56:#57 // in:Ljava/io/InputStream;
#39 = Class #58 // java/io/InputStream
#40 = NameAndType #59:#52 // read:()I
#41 = Utf8 java/lang/Object
#42 = Utf8 java/lang/InterruptedException
#43 = Utf8 java/lang/NoSuchFieldException
#44 = Utf8 java/lang/IllegalAccessException
#45 = Utf8 java/io/IOException
#46 = Utf8 java/lang/Class
#47 = Utf8 getAnnotation
#48 = Utf8 (Ljava/lang/Class;)Ljava/lang/annotation/Annotation;
#49 = Utf8 java/lang/System
#50 = Utf8 out
#51 = Utf8 Ljava/io/PrintStream;
#52 = Utf8 ()I
#53 = Utf8 java/io/PrintStream
#54 = Utf8 println
#55 = Utf8 (I)V
#56 = Utf8 in
#57 = Utf8 Ljava/io/InputStream;
#58 = Utf8 java/io/InputStream
#59 = Utf8 read
{
public TestMain();
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 static void main(java.lang.String[]) throws java.lang.InterruptedException, java.lang.NoSuchFieldException, java.lang.IllegalAccessException, java.io.IOException;
descriptor: ([Ljava/lang/String;)V
flags: ACC_PUBLIC, ACC_STATIC
Code:
stack=2, locals=2, args_size=1
0: ldc #2 // class TestMain
2: ldc #3 // class TestAnnotation
4: invokevirtual #4 // Method java/lang/Class.getAnnotation:(Ljava/lang/Class;)Ljava/lang/annotation/Annotation;
7: checkcast #3 // class TestAnnotation
10: astore_1
11: getstatic #5 // Field java/lang/System.out:Ljava/io/PrintStream;
14: aload_1
15: invokeinterface #6, 1 // InterfaceMethod TestAnnotation.count:()I
20: invokevirtual #7 // Method java/io/PrintStream.println:(I)V
23: getstatic #8 // Field java/lang/System.in:Ljava/io/InputStream;
26: invokevirtual #9 // Method java/io/InputStream.read:()I
29: pop
30: return
LineNumberTable:
line 5: 0
line 6: 11
line 7: 23
line 8: 30
Exceptions:
throws java.lang.InterruptedException, java.lang.NoSuchFieldException, java.lang.IllegalAccessException, java.io.IOException
}
SourceFile: "TestMain.java"
RuntimeVisibleAnnotations:
0: #25(#26=I#27)
TestAnnotation.class 反编译
javap -v TestAnnotation.class
Classfile /Users/yanglihua/Desktop/temp/TestAnnotation.class
Last modified May 15, 2019; size 435 bytes
MD5 checksum c5a4be1e3536f21be7b8a71cf354073a
Compiled from "TestAnnotation.java"
public interface TestAnnotation extends java.lang.annotation.Annotation
minor version: 0
major version: 52
flags: ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT, ACC_ANNOTATION
Constant pool:
#1 = Class #18 // TestAnnotation
#2 = Class #19 // java/lang/Object
#3 = Class #20 // java/lang/annotation/Annotation
#4 = Utf8 count
#5 = Utf8 ()I
#6 = Utf8 AnnotationDefault
#7 = Integer 1
#8 = Utf8 SourceFile
#9 = Utf8 TestAnnotation.java
#10 = Utf8 RuntimeVisibleAnnotations
#11 = Utf8 Ljava/lang/annotation/Target;
#12 = Utf8 value
#13 = Utf8 Ljava/lang/annotation/ElementType;
#14 = Utf8 TYPE
#15 = Utf8 Ljava/lang/annotation/Retention;
#16 = Utf8 Ljava/lang/annotation/RetentionPolicy;
#17 = Utf8 RUNTIME
#18 = Utf8 TestAnnotation
#19 = Utf8 java/lang/Object
#20 = Utf8 java/lang/annotation/Annotation
{
public abstract int count();
descriptor: ()I
flags: ACC_PUBLIC, ACC_ABSTRACT
AnnotationDefault:
default_value: I#7}
SourceFile: "TestAnnotation.java"
RuntimeVisibleAnnotations:
0: #11(#12=[e#13.#14])
1: #15(#12=e#16.#17)
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