获取Java Bean的映射属性

/** 
 来自 N o w J a v a . c o m - 时  代  Java**/


//package com.nowjava;

import java.beans.BeanInfo;


import java.beans.IntrospectionException;

import java.beans.Introspector;

import java.beans.PropertyDescriptor;


import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;


public class Main {

    private static final String MAPPED_DELIM = "(";

    private static final String MAPPED_DELIM2 = ")";


    public static Object getMappedProperty(Object bean, String name)

            throws IllegalArgumentException, IllegalAccessException,

            InvocationTargetException {

        int delim = name.indexOf(MAPPED_DELIM);

        int delim2 = name.indexOf(MAPPED_DELIM2);/** 来 自 nowjava - 时  代  Java**/

        if ((delim < 0) || (delim2 <= delim))

            throw new IllegalArgumentException("Invalid mapped property '"

                    + name + "'");

        String subscript = name.substring(delim + 1, delim2);

        name = name.substring(0, delim);

        return getMappedProperty(bean, name, subscript);

    }


    public static Object getMappedProperty(Object bean, String name,

            String key) throws IllegalArgumentException,

            IllegalAccessException, InvocationTargetException {

        PropertyDescriptor propertyDescriptor = getPropertyDescriptor(bean,

                name);

        if (propertyDescriptor == null)

            throw new IllegalArgumentException("No property:" + name);

        Method readMethod = propertyDescriptor.getReadMethod();

        if (readMethod == null)

            throw new IllegalArgumentException(

                    "No readMethod for property:" + name);

        Object map = readMethod.invoke(bean, new Object[0]);

        if (!(map instanceof java.util.Map))

            throw new IllegalArgumentException("Property '" + name

                    + "' is not mapped");

        return ((java.util.Map<?, ?>) map).get(key);

    }


    public static PropertyDescriptor getPropertyDescriptor(Object bean,

            String name) {

        PropertyDescriptor[] descriptors = getPropertyDescriptors(bean);

        for (int i = 0; i < descriptors.length; i++) {

            if (name.equals(descriptors[i].getName()))

                return descriptors[i];

        }