BeanUtils

阳光穿透心脏的1/2处 2021-09-23 01:18 317阅读 0赞

# BeanUtils #

本文是基于Windows 10系统环境，学习和使用BeanUtils：

*  **Windows 10**
 *  **MyEclipse 10**
 *  **[commons-beanutils-1.8.jar][]**
 *  **[commons-logging-1.1.3.jar][]**

--------------------

## 一、 BeanUtils的基本概念 ##

### (1) BeanUtils的定义 ###

*  **Apache 组织提供的一个开源工具类库**

### (2) BeanUtils的作用 ###

*  **程序中对javabean的操作很频繁， 所以apache提供了一套开源的api，方便对javabean的操作！即BeanUtils组件**

### (3) 使用BeanUtils组件需要引入的jar包 ###

*  **[commons-beanutils-1.8.jar][]**
 *  **[commons-logging-1.1.3.jar][]**

### (4) BeanUtils的核心API ###

*  **方法1： 对象属性的拷贝**

BeanUtils.copyProperty(admin, "userName", "jack");
    BeanUtils.setProperty(admin, "age", 18);

*  **方法2： 对象的拷贝**

BeanUtils.copyProperties(newAdmin, admin);

*  \*\*方法3： map数据拷贝到javabean中 \*\*

BeanUtils.populate(adminMap, map);

### (4) BeanUtils的实例 ###

*  **Admin.java**

package com.inspur.a_beans;
    /** * ClassName: Admin * Function: TODO ADD FUNCTION * @author: xuzheng * date: 2019-5-21 ÉÏÎç9:38:14 */
    public class Admin { 
    	private int id;
    	private String userName;
    	private String pwd;
    	public int getId() { 
    		return id;
    	}
    	public void setId(int id) { 
    		this.id = id;
    	}
    	public String getUserName() { 
    		return userName;
    	}
    	public void setUserName(String userName) { 
    		this.userName = userName;
    	}
    	public String getPwd() { 
    		return pwd;
    	}
    	public void setPwd(String pwd) { 
    		this.pwd = pwd;
    	}
    	@Override
    	public String toString() { 
    		return "Admin [id=" + id + ", userName=" + userName + ", pwd=" + pwd
    				+ "]";
    	}
    	
    }

*  **Demo.java**

package com.inspur.a_beans;
    
    import java.util.HashMap;
    import java.util.Map;
    import org.apache.commons.beanutils.BeanUtils;
    import org.junit.Test;
    
    /** * ClassName: Demo * Function: TODO ADD FUNCTION * @author: xuzheng * date: 2019-5-21 上午9:37:03 */
    public class Demo { 
    	@Test
    	public void test1() throws Exception{ 
    		//a.基本操作
    		Admin admin = new Admin();
    // admin.setUserName("tom");
    // admin.setPwd("123456");
    		
    		//b.BeanUtils组件实现对象属性的赋值，实现原理：反射
    		BeanUtils.setProperty(admin, "id", 2);
    		BeanUtils.setProperty(admin, "userName", "tom");
    		BeanUtils.setProperty(admin, "Pwd", "123456");
    		
    		//c.BeanUtils组件实现对象的拷贝
    		Admin newAdmin = new Admin();
    		BeanUtils.copyProperties(newAdmin, admin);
    		
    		//d.map数据，拷贝到对象中
    		Admin adminMap = new Admin();
    		Map<String, Object> map = new HashMap<String, Object>();
    		map.put("id", 3);
    		map.put("userName", "eric");
    		map.put("pwd", "123456");
    		BeanUtils.populate(adminMap, map);
    		System.out.println(adminMap);
    	}
    	@Test 
    	public void test2() throws Exception{ 
    		//a.基本操作
    		Admin admin = new Admin();
    		String name = "tom";
    		String pwd = "1234";
    		String birth = "1999-09-09";
    		
    		//注册日期类型转换器，使用组件提供的转换器工具类
    		ConvertUtils.register(new DateLocaleConverter(), Date.class);
    		
    		//b.BeanUtils组件实现对象属性的赋值，实现原理：反射
    		BeanUtils.copyProperty(admin, "id", 2);
    		BeanUtils.copyProperty(admin, "userName", name);
    		BeanUtils.copyProperty(admin, "pwd", pwd);
    		BeanUtils.copyProperty(admin, "birth", birth);
    		System.out.println(admin);
    	}
    }

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[commons-beanutils-1.8.jar]: http://commons.apache.org/proper/commons-beanutils/download_beanutils.cgi
[commons-logging-1.1.3.jar]: http://commons.apache.org/proper/commons-logging/download_logging.cgi