Java通过反射获取自定义注解

• 需要的几个jar包
  1.reflections-0.9.10.jar 反射包
  2.guava-15.0.jar 反射的依赖包
  3.javassist-3.18.2-GA.jar 反射的依赖包

• 自定义注解类

import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;@Target(ElementType.TYPE)@Retention(RetentionPolicy.RUNTIME)public @interface Controller {    String value() default "/";}

• 测试类1

@Controller("/test1")public class Test1 {}

• 测试类2

@Controller("test2")public class Test2 {}

• 测试类3

@Controller("/test3")public class Test3 {}

• 整体功能代码

import java.util.HashMap;import java.util.Map;import java.util.Set;import org.reflections.Reflections;public class AnnotationTest {    private static final String CONTROLLER_PACK = "com.lzy.*";    public static void main(String[] args) {        Map<String, Class> map = getControllerAnnotation();        for (Map.Entry<String, Class> m : map.entrySet()) {            System.out.println("Value:" + m.getKey() + "----" + "Class:" + m.getValue());        }    }    /**     * 获取注解的controller     *      * @return     */    @SuppressWarnings("rawtypes")    public static Map<String, Class> getControllerAnnotation() {        Map<String, Class> result = new HashMap<String, Class>();        //指定反射扫描包        Reflections reflections = new Reflections(CONTROLLER_PACK);        //获取注解类型的set集合数据        Set<Class<?>> classes = reflections.getTypesAnnotatedWith(Controller.class);        //存储到结果集        for (Class clazz : classes) {            Controller controller = (Controller) clazz.getAnnotation(Controller.class);            String value = controller.value();            result.put(value, clazz);        }        return result;    }}

• 运行结果