使用BeanUtils工具包操作JavaBean-2

在操作之前就先下Apache官网上下载相就的工具，这里我们要下载commons-beanutils 和commons-logging,我下载的版本是commons-beanutils-1.8.3和commons-logging-1.1.1，然后我选择的是commons-beanutils-1.8.3.jar和commons-logging-1.1.1.jar这两个jar包

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演示用Eclipse如何加入jar包，先只是引入beanutils包，等程序运行出错后再引入logging包

在前面的内省例子的基础上，用BeanUtils类先get原来设置好的属性，再将其set为一个新值。

get属性时返回的结果为该属性本来的类型，set属性时只接受该属性本来的类型。、

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BeanUtils.setProperty(pt1, "x","9"); //这里的9是String类型

PropertyUtils.setProperty(pt1, "x", 9); //这里的是int类型

//这两个类BeanUtils和PropertyUtils,前者能自动将int类型转化，后者不能

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;import org.apache.commons.beanutils.BeanUtils;import org.apache.commons.beanutils.PropertyUtils;public class IntroSpectorTest {public static void main(String[] args) throws Exception{ReflectPoint1 pt1 = new ReflectPoint1(3,5);String propertyName = "x";Object retval = getProperty(pt1, propertyName);System.out.println(retval);Object value = 7;setProperty(pt1, propertyName, value);System.out.println(BeanUtils.getProperty(pt1, "x")); //这里使用了Apache公司开发的BeanUtils工具包BeanUtils.setProperty(pt1, "x","9"); //这里的9是String类型PropertyUtils.setProperty(pt1, "x", 9); //这里的是int类型//这两个类BeanUtils和PropertyUtils,前者能自动将int类型转化，后者不能System.out.println(pt1.getX());BeanUtils.setProperty(pt1, "birthday.time", "111"); //一级一级调用实现System.out.println(BeanUtils.getProperty(pt1, "birthday.time"));//Map map = {name:"xxx",age:18}; java 7新特性//BeanUtils.setProperty(map, "name", "zzz"); 可以实现map功能}private static void setProperty(Object pt1, String propertyName,Object value) throws IntrospectionException,IllegalAccessException, InvocationTargetException {PropertyDescriptor pd2 = new PropertyDescriptor(propertyName, pt1.getClass()); //propertyName为字段名//javaBean的操作方式Method methodSetx = pd2.getWriteMethod(); //调用该字段的setxxx方法methodSetx.invoke(pt1, value);}private static Object getProperty(Object pt1, String propertyName)throws IntrospectionException, IllegalAccessException,InvocationTargetException {/*PropertyDescriptor pd = new PropertyDescriptor(propertyName, pt1.getClass());Method methodGetX = pd.getReadMethod();//调用该字段的getxxxx方法Object retval = methodGetX.invoke(pt1);return retval;*/BeanInfo beaninfo = Introspector.getBeanInfo(pt1.getClass());PropertyDescriptor[] pds = beaninfo.getPropertyDescriptors();Object retVal = null;for (PropertyDescriptor pd: pds) {if (pd.getName().equals(propertyName)) {Method methodGetX = pd.getReadMethod();retVal = methodGetX.invoke(pt1);break;}}return retVal;}}

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