使用反射复制一个JavaBean的对象

先看代码吧：

package com.java.study;

import java.io.Serializable;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class ReflectTester {
    public Object copy(Object object) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {
        Class classType = object.getClass();//获得对象的类型
        System.out.println("Class:" + classType.getName());

        //通过默认的构造函数创建一个新的对象
        Object objectCopy = classType.getConstructor(new Class[] {}).
        newInstance(new Object[] {});

        //获得对象的所有属性
        Field fields[] = classType.getDeclaredFields();

        for(int i = 0; i < fields.length; i++) {
            Field field = fields[i];

            String fieldName = field.getName();
            String firstLetter = fieldName.substring(0,1).toUpperCase();
            //获得和属性对应的getXXX（）方法的名字
            String getMethodName = "get" + firstLetter + fieldName.substring(1);
            //获得和属性对应的setXXX()方法的名字
            String setMethodName = "set" + firstLetter + fieldName.substring(1);

            //获得和属性对应的getXXX()方法
            Method getMethod = classType.getMethod(getMethodName, new Class[]{});
            //获得和属性对应的setXXX()方法
            Method setMethod = classType.getMethod(setMethodName, new Class[]{field.getType()});

            //调用原对象的getXXX()方法
            Object value = getMethod.invoke(object, new Object[]{});
            System.out.println(fieldName + ":" + value);
            //调用复制对象的setXXX()方法
            setMethod.invoke(objectCopy, new Object[]{value});
        }
        return objectCopy;

    }

    public static void main(String[] args) throws IllegalArgumentException, SecurityException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {
        Customer1 customer = new Customer1("tom",21);
        customer.setId(new Long(1));

        Customer1 customerCopy = (Customer1) new ReflectTester().copy(customer);
        System.out.println("Copy information:" + customerCopy.getName()+ ""
                +customerCopy.getAge());
    }

}

class Customer1 implements Serializable {

    private Long id;
    private String name;
    private int age;

    public Customer1() {}
    public Customer1(String name, int age){
        this.name = name;
        this.age = age;
    }

    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}

代码中有一个Customer1的JavaBean,通过反射复制了一个Customer1类的对象，为customerCopy，程序中的new Class[] { }是一种快捷方式，获得方法的引用。[]中用来放参数，｛｝里面可以放置方法的返回类型。new Class[] { }相当于new class("构造函数参数").newinstance.

//调用原对象的getXXX()方法
      Object value = getMethod.invoke(object, new Object[]{});
      System.out.println(fieldName + ":" + value);

用来获得特定对象的特定方法。