自定义Annotation-蒲公英云

自定义Annotation

package com.test.javaSe01;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.reflect.Method;
@Retention(value = RetentionPolicy.RUNTIME)
// 此句必须有//\u6B64\u53E5\u5FC5\u987B\u6709
@interface MySelfAnnotation {
    public int age() default 23;
    public String name() default "ctl";
}
@MySelfAnnotation(age = 100, name = "蔡腾林")
class Person {
    int age;
    String name;
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int hashCode() {
        return super.hashCode();
    }
    @MySelfAnnotation(age = 230, name = "ctllin")
    public String toString() {
        return this.name + " " + this.age;
    }
    @MySelfAnnotation
    public void print() {
    }
}
/**
 * 
 * @author Administrator
 * @deprecated 获取自定义Annotation中的值 自定义的Annotation分别定义到类和方法上
 */
public class SelfAnnotationTestDemo {
    public static void main(String[] args) {
        SelfAnnotationTestDemo sa = new SelfAnnotationTestDemo();
        Class<?> c = null;
        try {
            c = Class.forName("com.test.javaSe01.Person");
            if (c.isAnnotationPresent(MySelfAnnotation.class)) {
                MySelfAnnotation ma = c.getAnnotation(MySelfAnnotation.class);
                System.out.println(ma.name() + " " + ma.age());
            }
        } catch (ClassNotFoundException e) {
            System.err.println("com.test.javaSe01.Person没有找到");
            e.printStackTrace();
        }
        Method method = null, method1 = null;
        try {
            method = c.getMethod("toString");
            System.out.println(method);
            method1 = c.getMethod("print");
            System.out.println(method1);
        } catch (SecurityException e) {
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        }
        if (method.isAnnotationPresent(MySelfAnnotation.class)) {
            MySelfAnnotation myAnnotation = method
                    .getAnnotation(MySelfAnnotation.class);
            int age = myAnnotation.age();
            String name = myAnnotation.name();
            System.out.println(name + " " + age);
        }
        if (method1.isAnnotationPresent(MySelfAnnotation.class)) {
            MySelfAnnotation myAnnotation = method1
                    .getAnnotation(MySelfAnnotation.class);
            int age = myAnnotation.age();
            String name = myAnnotation.name();
            System.out.println(name + " " + age);
        }
    }
}