JAVA反射学习（1）

 

 

 

 

1

 

 

package com.langsin.reflection;

import java.lang.reflect.Method;

public class DumpMethods {
	public static  void main(String[] args)throws Exception {
		//加载并初始化命令行参数指定的类
		Class<?> classType = Class.forName(args[0]);
		//得到当前类声明的所有方法，包括private
		Method[] methods = classType.getDeclaredMethods();
		//下面这个方法是得到当前类及其实现接口和超类的所有public方法
		//Method[] methods = classType.getMethods();
		for(int i=0;i<methods.length;i++){
			System.out.println(methods[i].toString());
		}
	}
}

 

 

package com.langsin.reflection;


import java.lang.reflect.Field;
import java.lang.reflect.Method;

public class ReflectTester
{
    public Object copy(Object object) throws Exception
    {
        // 获得对象的类型
        Class<?> classType = object.getClass();
        System.out.println("Class:" + classType.getName());

        // 通过默认构造方法创建当前类的一个实例
        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);
            // 调用拷贝对象的setXXX()方法
            setMethod.invoke(objectCopy, new Object[] { value });
        }
        return objectCopy;
    }

    public static void main(String[] args) throws Exception
    {
        Customer customer = new Customer("Tom", 21);
        customer.setId(new Long(1));

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

class Customer
{
    private Long id;

    private String name;

    private int age;

    public Customer()
    {
    }

    public Customer(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;
    }
}