JDK动态代理+反射实现动态修改注解属性值

public class ModifyAnnotaionFactory {
private static ModifyAnnotaionFactory instance = null;
public static ModifyAnnotaionFactory newInstance()
{ if (instance == null)
{
synchronized (ModifyAnnotaionFactory.class)
{
if (instance == null)
{
instance = new ModifyAnnotaionFactory();
}
}
} return instance;
}
private ModifyAnnotaionFactory(){} /**
*
* @param className 当前类名.class
* @param annotationName 需要修改的注解class
* @param methodName 需要修改的方法名
* @param modifyField 注解中需要修改的属性名
* @param paramName 注解中修改的属性值
* @param paramTypes 不定参数----语法糖
*/
public Annotation ModifyAnnotation(Class className,Class annotationName,
String methodName,String modifyField,String paramName,Class<?>... paramTypes)
{
try
{
//反射获取Method：methodName方法、paramTypes不定参数（“语法糖”）-----method
Method method = className.getDeclaredMethod(methodName,paramTypes);
//反射当前方法的注解---annotation
Annotation annotation = method.getAnnotation(annotationName);
//获取该注解的调用处理器---invocationHandler
InvocationHandler invocationHandler = Proxy.getInvocationHandler(annotation);
//反射获取注解的属性
Field memberValues = invocationHandler.getClass().getDeclaredField("memberValues");
//暴力破解
memberValues.setAccessible(true);
//获取所有的注解属性--map集合
Map<String, Object> values = (Map<String, Object>) memberValues.get(invocationHandler);
//覆盖原有属性值
values.put(modifyField, paramName);
return annotation;
} catch (Exception e) {
e.printStackTrace();
return null;
}
} /**
*
* @param classAllPath 当前类的全路径名
* @param annotationName 需要修改的注解class
* @param methodName 需要修改的方法名
* @param modifyField 注解中需要修改的属性名
* @param paramName 注解中修改的属性值
* @return
*/
public boolean ModifyAnnotation(String classAllPath,Class annotationName,String methodName,String modifyField,String paramName)
{
try
{
Class<?> aClass = Class.forName(classAllPath);
Method method = aClass.getDeclaredMethod(methodName);
Annotation annotation = method.getAnnotation(annotationName);
InvocationHandler invocationHandler = Proxy.getInvocationHandler(annotation);
Field memberValues = invocationHandler.getClass().getDeclaredField("memberValues");
memberValues.setAccessible(true);
Map<String, Object> values = (Map<String, Object>) memberValues.get(invocationHandler); Object o1 = values.get(modifyField);
values.put(modifyField, paramName);
Object o2 = values.get(modifyField);
System.out.println();
return true;
} catch (Exception e) {
e.printStackTrace();
return false;
}
} /**
* 获取当前注解
* @param className 当前类名
* @param annotationName 注解名
* @param name 方法名、类名、属性名之一
* @param type 注解类型
* @return
* @throws Exception
*/
public Annotation getAnnotation(Class className,Class annotationName,String name,Integer type) throws Exception {
switch (type){
case 1:
Method method = className.getDeclaredMethod(name);
return method.getAnnotation(annotationName);
case 2:
System.out.println("2");
return null;
case 3:
System.out.println("3");
return null;
}
return null;
}