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，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对网站的支持！