JAVA 自定义注解及参数获取

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package com.java.annotation;import java.lang.annotation.*;/** * Created by lw on 14-5-30. * 自定义注解 */@Documented@Target(ElementType.METHOD)@Retention(RetentionPolicy.RUNTIME)public @interface MethodInfo {    public String Value() default "暂无说明";}/*四个定义注解时候的限定数据@Target(ElementType.TYPE)           :接口、类、枚举、注解@Target(ElementType.FIELD)          :字段、枚举的常量@Target(ElementType.METHOD)         :方法@Target(ElementType.PARAMETER)      :方法参数@Target(ElementType.CONSTRUCTOR)    :构造函数@Target(ElementType.LOCAL_VARIABLE) :局部变量@Target(ElementType.ANNOTATION_TYPE):注解@Target(ElementType.PACKAGE)        :包@Retention(RetentionPolicy.SOURCE)  :在源文件中有效（即源文件保留）@Retention(RetentionPolicy.CLASS)   :在class文件中有效（即class保留）@Retention(RetentionPolicy.RUNTIME) :在运行时有效（即运行时保留）@Inherited：说明子类可以继承父类中的该注解@Document：说明该注解将被包含在javadoc中*/

package com.java.annotation;import java.lang.annotation.Annotation;import java.lang.reflect.Method;/** * Created by lw on 14-5-30. */public class Test {    /**     * 获取注解参数     *     * @param annotationClass 注解类     * @param annotationField 注解类字段名称     * @param aClass          使用注解的class名称     * @param methodName      使用注解的方法名称     * @throws Exception     */    public static void getAnnotationPar(Class annotationClass, String annotationField, Class aClass, String methodName) throws Exception {        Method aClassMethod = aClass.getMethod(methodName);        Annotation annotation = aClassMethod.getAnnotation(annotationClass);        Method method = annotation.getClass().getDeclaredMethod(annotationField);        System.out.println(method.invoke(annotation));    }    public static void main(String[] args) throws Exception {        Test.getAnnotationPar(MethodInfo.class, "Value", Test2Annotation.class, "testMyAnnotation");    }}class Test2Annotation {    @MethodInfo(Value = "自定义的注解@MethodInfo")    public void testMyAnnotation() {    }}

源码：https://github.com/xiaohulu/util_xiaohulu/tree/master/src/com/java/annotation

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