자바 사용자 정의 주석

package com.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.FIELD) //          
public @interface TestAnnField {
	public String value() default ""; 
}

 

package com.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD) //          
public @interface TestAnnoMethod {

	String types() default "";//      ，               types  ， @TestAnnoMethod(username = "cyss") ，       
	String username() ;
}

 

package com.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
//       ，       。 @Target(ElementType.FIELD) FIELD:      ，       
/*
 * 　1.CONSTRUCTOR:        　　　　2.FIELD:      　　　　3.LOCAL_VARIABLE:        
 * 　　　　4.METHOD:       　　　　5.PACKAGE:      　　　　6.PARAMETER:      
 * 　　　　7.TYPE:     、  (      )  enum  
 */
public @interface TestAnnoType {
	Class<?> type();

	String method();//                 

	Class<?>[] args();

	String value() default "";
}

 

package com.annotation;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Method;

@TestAnnoType(args = { Test.class,Test2.class }, method = "getUserAll", type = Test.class)
public class Test {

	@TestAnnField(value = "  ")
	private String name;
	
	@TestAnnField(value = "sfd")
	private String age;
	
	@TestAnnField(value = " ")
	private String sex;
	
	private String adr;
	
	@TestAnnoMethod(username = "cyss")
	public void methodAnno(){
		System.out.println("Method||01");
	}
	
	@TestAnnoMethod(username = "xxxxxx")
	public void methodAnno2(){
		System.out.println("Method||02");
	}

	public static void main(String[] args){

		Test.aminType();
		try {
			 Class<Test> c = Test.class;
			 
			 //         
			 Field field = c.getDeclaredField("name");
			 
			 //         
			 if(field.isAnnotationPresent(TestAnnField.class)){
				 System.out.println("true");
			 }
			
			Test s = (Test)Class.forName("com.annotation.Test").newInstance();
			System.out.println("  :"+s.name);
		} catch (Exception e) {	
			System.out.println("NO");
			e.printStackTrace();
		}
	}
	
	/**
	 *          
	 */
	public static void aminType(){
		Test test = new Test();
		
		try {
			Class<Test> c = Test.class;
			Class classs = Class.forName("com.annotation.Test");
			
			TestAnnoType  annoType = (TestAnnoType) classs.getAnnotation(TestAnnoType.class);
			String methodStr = annoType.method();
			Class classType = annoType.type();
			Class[] classTypes = annoType.args();
			
			System.out.println("&&"+methodStr);
			System.out.println("&&"+classType);
			
			System.out.println("&&"+classTypes[0]);
			System.out.println("&&"+classTypes[1]);
			
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 *          
	 */
	public static void mainMethod() {
		Test test = new Test();
		try {
			//          
			Class<Test> c = Test.class;
			Method method = c.getMethod("methodAnno", new Class[] {});
			
			TestAnnoMethod anoMethod = method.getAnnotation(TestAnnoMethod.class);  
			String name = anoMethod.username();  
			System.out.println("methodAnno     ："+name);
			
			//        
			for (Method method2 : c.getDeclaredMethods()) {  
				TestAnnoMethod anoMethod2 = method2.getAnnotation(TestAnnoMethod.class); 
				  if (anoMethod2 != null) {
					  System.out.println("   :"+method2.getName()+"   :"+anoMethod2.username());
				  }  
			}	
			
			
			//           
			Annotation[] annotations = method.getAnnotations();
			for (Annotation annotation : annotations) {
				System.out.println("        "+annotation);
				
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		test.methodAnno();
	}
	
	/**
	 *       
	 */
	public static void mainFields() {
		Test test = new Test();
		try {
			Field[] methods = Test.class.getDeclaredFields();

			for (Field method : methods) {
				boolean hasAnnotation = method
						.isAnnotationPresent(TestAnnField.class);
				
				if (hasAnnotation) {
					TestAnnField value = method
							.getAnnotation(TestAnnField.class);
					method.set(test, value.value());
				}
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println("||"+test.name);
		System.out.println("||"+test.age);
		System.out.println("||"+test.sex);
		System.out.println("||"+test.adr);
	}
}