反射的工具类

/**  
 * Date:2017年10月15日下午5:09:57 
 * Copyright (c) 2017, [e-mail] All Rights Reserved. 
 * 
*/
/**   


* @Description: TODO
* @author 程昭昭 [e-mail]   
* @date 2017年10月15日 下午5:09:57 
  
*/


package com.czz.ehzc.tools;


import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;


/** 
 * ClassName:ReflectionUtils <br/> 
 * Function: TODO ADD FUNCTION. <br/> 
 * Reason:   TODO ADD REASON. <br/> 
 * Date:     2017年10月15日 下午5:09:57 <br/> 
 * @author   czz19 
 * @version   
 * @since    JDK 1.8 
 * @see       
 */
/**
 * @Description: TODO
 * @author [e-mail] 程昭昭
 * @date 2017年10月15日 下午5:09:57
 * 
 */
public class ReflectionUtils {
/**
* 通过反射, 获得定义 Class 时声明的父类的泛型参数的类型 如: public EmployeeDao extends
* BaseDao<Employee, String>
* 
* @param clazz
* @param index
* @return
*/
@SuppressWarnings("rawtypes")
public static Class getSuperClassGenricType(Class clazz, int index) {
Type genType = clazz.getGenericSuperclass();


if (!(genType instanceof ParameterizedType)) {
return Object.class;
}


Type[] params = ((ParameterizedType) genType).getActualTypeArguments();


if (index >= params.length || index < 0) {
return Object.class;
}


if (!(params[index] instanceof Class)) {
return Object.class;
}


return (Class) params[index];
}


/**
* 通过反射, 获得 Class 定义中声明的父类的泛型参数类型 如: public EmployeeDao extends
* BaseDao<Employee, String>
* 
* @param <T>
* @param clazz
* @return
*/
@SuppressWarnings({ "unchecked", "rawtypes" })
public static <T> Class<T> getSuperGenericType(Class clazz) {
return getSuperClassGenricType(clazz, 0);
}


/**
* 循环向上转型, 获取对象的 DeclaredMethod
* 
* @param object
* @param methodName
* @param parameterTypes
* @return
*/
public static Method getDeclaredMethod(Object object, String methodName, Class<?>[] parameterTypes) {


for (Class<?> superClass = object.getClass(); superClass != Object.class; superClass = superClass
.getSuperclass()) {
try {
// superClass.getMethod(methodName, parameterTypes);
return superClass.getDeclaredMethod(methodName, parameterTypes);
} catch (NoSuchMethodException e) {
// Method 不在当前类定义, 继续向上转型
}
// ..
}


return null;
}


/**
* 使 filed 变为可访问
* 
* @param field
*/
public static void makeAccessible(Field field) {
if (!Modifier.isPublic(field.getModifiers())) {
field.setAccessible(true);
}
}


/**
* 循环向上转型, 获取对象的 DeclaredField
* 
* @param object
* @param filedName
* @return
*/
public static Field getDeclaredField(Object object, String filedName) {


for (Class<?> superClass = object.getClass(); superClass != Object.class; superClass = superClass
.getSuperclass()) {


try {
Field field = null;
// makeAccessible(field);

field = superClass.getDeclaredField(filedName.toLowerCase());


return field;
} catch (NoSuchFieldException e) {
// Field 不在当前类定义, 继续向上转型
e.printStackTrace();
}
}
return null;
}


/**
* 直接调用对象方法, 而忽略修饰符(private, protected)
* 
* @param object
* @param methodName
* @param parameterTypes
* @param parameters
* @return
* @throws InvocationTargetException
* @throws IllegalArgumentException
*/
public static Object invokeMethod(Object object, String methodName, Class<?>[] parameterTypes, Object[] parameters)
throws InvocationTargetException {


Method method = getDeclaredMethod(object, methodName, parameterTypes);


if (method == null) {
throw new IllegalArgumentException("Could not find method [" + methodName + "] on target [" + object + "]");
}


method.setAccessible(true);


try {
return method.invoke(object, parameters);
} catch (IllegalAccessException e) {
System.out.println("不可能抛出的异常");
}


return null;
}


/**
* 直接设置对象属性值, 忽略 private/protected 修饰符, 也不经过 setter
* 
* @param object
* @param fieldName
* @param value
*/
public static void setFieldValue(Object object, String fieldName, Object value) {
Field field = getDeclaredField(object, fieldName);

if (field == null) {
throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + object + "]");
   
}
makeAccessible(field);

try {
//System.out.println(value.getClass().toString());
if(value.getClass().toString().equals("class java.math.BigDecimal")) {
value = Integer.parseInt(value.toString());
}
field.set(object, value);
} catch (IllegalAccessException e) {
System.out.println("不可能抛出的异常");
}
}


/**
* 直接读取对象的属性值, 忽略 private/protected 修饰符, 也不经过 getter
* 
* @param object
* @param fieldName
* @return
*/
public static Object getFieldValue(Object object, String fieldName) {
Field field = getDeclaredField(object, fieldName);
// @test
System.out.println(field);
if (field == null)
throw new IllegalArgumentException("Could not find field [" + fieldName + "] on target [" + object + "]");


makeAccessible(field);


Object result = null;


try {
result = field.get(object);
} catch (IllegalAccessException e) {
System.out.println("不可能抛出的异常");
}


return result;
}
}