设置豆

/**

 * Copyright 2008-2009 the original author or authors.

 *

 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in

 * compliance with the License. You may obtain a copy of the License at:

 *

 * http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software distributed under the License is

 * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and limitations under the License. 

 */

//package com.nowjava;

import java.beans.IntrospectionException;
/*
 from nowjava.com - 时代Java 
*/

import java.beans.PropertyDescriptor;


import java.lang.reflect.Field;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;


public class Main {



    public static void setBean(Object obj, String beanPath, Object value)//from 时 代 J a v a 公 众 号

            throws IllegalStateException {

        try {

            if (beanPath.indexOf('.') > -1) {

                String name = beanPath.substring(0, beanPath.indexOf('.'));

                String path = beanPath.substring(beanPath.indexOf('.') + 1);

                Field field = findField(obj, name);

                field.setAccessible(true);

                Object child = field.get(obj);

                if (child == null) {

                    throw new IllegalStateException(

                            "Choked on a null field '" + name + "' on "

                                    + obj.getClass().getName());

                }

                setBean(child, path, value);

            } else {

                setField(obj, beanPath, value);

            }

        } catch (IllegalAccessException e) {

            throw new RuntimeException(e);

        }

    }


    public static Field findField(Object obj, String beanPath) {

        try {

            if (beanPath.indexOf('.') > -1) {

                String name = beanPath.substring(0, beanPath.indexOf('.'));

                String path = beanPath.substring(beanPath.indexOf('.') + 1);

                Field field = obj.getClass().getDeclaredField(name);

                field.setAccessible(true);

                return findField(field.get(obj), path);

            } else if (obj == null) {

                return null;

            } else {

                return obj.getClass().getDeclaredField(beanPath);

            }

        } catch (NoSuchFieldException e) {

            return null;

        } catch (IllegalAccessException e) {

            throw new RuntimeException(e);

        }

    }


    public static void setField(Object parent, String fieldName,

            Object value) {

        try {

            Method method = findSetter(parent, fieldName);

            if (method != null) {

                method.setAccessible(true);

                method.invoke(parent, new Object[] { value });

            } else {

                Field field = parent.getClass().getDeclaredField(fieldName);

                field.setAccessible(true);

                field.set(parent, value);

            }

        } catch (IllegalAccessException e) {

            throw new RuntimeException(e);

        } catch (InvocationTargetException e) {

            throw new RuntimeException(e);

        }