使用java的注解(用在java类的方法上的注解)方法

场景:根据方法上的注解,通过java反射方式找到需要执行的的方法。

1.注解类

/**注解作用在方法上*/
@target({elementtype.method}) 
/**注解的生命周期一直程序运行时都存在vm运行期间保留注解，可以通过反射机制读取注解信息*/
@retention(retentionpolicy.runtime)
/**注解包含在javadoc中*/
@documented 
public @interface item {
	string value();
}

2.在类的方法上使用注解

public class workservice {
 
	private static logger logger = loggerfactory.getlogger(workservice.class);
 
	@item("1001")
	public int getitem1001info(girlvo girl) {
 
		logger.info("getitem1001info输出:");
		logger.info(girl.tostring());
		return 1;
	}
	@item("1002")
	public int getitem1002info(girlvo girl) {
 
		logger.info("getitem1002info输出:");
		logger.info(girl.tostring());
		return 1;
	}
	@item("1003")
	public int getitem1003info(girlvo girl) {
		logger.info("getitem1003info输出:");
		logger.info(girl.tostring());
		return 1;
	}
	@item("1004")
	public int getitem1004info(girlvo girl) {
		logger.info("getitem1004info输出:");
		logger.info(girl.tostring());
		return 1;
	}
	@item("1005")
	public int getitem1005info(girlvo girl) {
		logger.info("getitem1005info输出:");
		logger.info(girl.tostring());
		return 1;
	}
	@item("1006")
	public int getitem1006info(girlvo girl) {
		logger.info("getitem1006info输出:");
		logger.info(girl.tostring());
		return 1;
	}
}

3.实体类,作为参数传递

public class girlvo implements serializable {
 
	private static final long serialversionuid = -8545755852948661858l;
	/**id号*/
	private string girlid;
	/**姓名*/
	private string girlname;
	/**年龄*/
	private long age;
	/**身高*/
	private double height;
	/**罩杯*/
	private string cupsize;
	public string getgirlid() {
		return girlid;
	}
	public void setgirlid(string girlid) {
		this.girlid = girlid;
	}
	public string getgirlname() {
		return girlname;
	}
	public void setgirlname(string girlname) {
		this.girlname = girlname;
	}
	public long getage() {
		return age;
	}
	public void setage(long age) {
		this.age = age;
	}
	public double getheight() {
		return height;
	}
	public void setheight(double height) {
		this.height = height;
	}
	public string getcupsize() {
		return cupsize;
	}
	public void setcupsize(string cupsize) {
		this.cupsize = cupsize;
	}
 
	@override
	public string tostring() {
		
		return "girlvo [girlid=" + girlid
				+",girlname=" + girlname
				+",age=" + age
				+",height=" + height
				+",cupsize=" + cupsize
				+"]";
	}
}

4.反射调用方法注解的类

		 list<method> methods = methodutils.getmethodslistwithannotation(clazz,item.class);
		 for (method method : methods) {
			 for (annotation annotation : method.getdeclaredannotations()) {
				 if (annotation instanceof item){
					 string code = ((item) annotation).value();
					 if (objects.equals(item, code)){
						 try {	
							logger.info("注解号:" + code +" 执行开始...");
							method.invoke(clazz.newinstance(), girlvo);
							logger.info("注解号:" + code +" 执行结束...");
						} catch (exception e) {
							e.printstacktrace();
							logger.info("抛异常...");
						}
					 }
				 }
			 }
		 }
 
	}
 
}

5.main方法测试类

public class testannotation {
	
	private static logger logger = loggerfactory.getlogger(testannotation.class);
	 
	public static void main(string []args) throws classnotfoundexception{
		logger.info("测试开始......");
		hashmap<string,object> map = (hashmap<string,object>) getdata();
		/**遍历hashmap*/
		for(entry<string,object> entry : map.entryset()){
			string item = entry.getkey();
			girlvo girlvo = (girlvo) entry.getvalue();
			reflectcallmethodannotation.annotationmethod(item,girlvo);
		}
		
		logger.info("测试结束......");
	}
 
 
	public static map getdata() {
 
		hashmap<string ,object> data = new hashmap();
		 
		girlvo girlvo1 = new girlvo();
		girlvo1.setgirlid("1001");
		girlvo1.setgirlname("张一");
		girlvo1.setage(27);
		girlvo1.setheight(169);
		girlvo1.setcupsize("f");
		
		girlvo girlvo2 = new girlvo();
		girlvo2.setgirlid("1002");
		girlvo2.setgirlname("王二");
		girlvo2.setage(29);
		girlvo2.setheight(175);
		girlvo2.setcupsize("b");
		
		girlvo girlvo3 = new girlvo();
		girlvo3.setgirlid("1003");
		girlvo3.setgirlname("刘五");
		girlvo3.setage(24);
		girlvo3.setheight(160);
		girlvo3.setcupsize("b");
		
		girlvo girlvo4 = new girlvo();
		girlvo4.setgirlid("1004");
		girlvo4.setgirlname("陈六");
		girlvo4.setage(21);
		girlvo4.setheight(168);
		girlvo4.setcupsize("c");
		
		girlvo girlvo5 = new girlvo();
		girlvo5.setgirlid("1005");
		girlvo5.setgirlname("赵七");
		girlvo5.setage(25);
		girlvo5.setheight(169);
		girlvo5.setcupsize("c");
		
		girlvo girlvo6 = new girlvo();
		girlvo6.setgirlid("1006");
		girlvo6.setgirlname("张八");
		girlvo6.setage(26);
		girlvo6.setheight(165);
		girlvo6.setcupsize("a");
		
		data.put("1001", girlvo1);
		data.put("1002", girlvo2);
		data.put("1003", girlvo3);
		data.put("1004", girlvo4);
		data.put("1005", girlvo5);
		data.put("1006", girlvo6);
		
		return data;
	}
 
}

以上所述是小编给大家介绍的使用java的注解(用在java类的方法上的注解)方法详解整合，希望对大家有所帮助