BeanUtils的简单使用

àì夳堔傛蜴生んèń 2022-02-03 05:39 218阅读 0赞

**首先需要导入apache两个包**

*  commons-beanutils-1.9.3.jar
 *  commons-logging-1.1.3.jar  
    然后buid path，如果没有导入commons-logging-1.1.3.jar将会出现下面这个错误  
      
    ![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDA1NjY2_size_16_color_FFFFFF_t_70]![在这里插入图片描述][20190508213002127.png]**接下来进入正题**  
    ![在这里插入图片描述][20190508213147724.png]  
    **注册器代码如下**
 *

//注册自定义转换器
    				//ConvertUtils.register(converter, clazz);
    				//参数1：转换器，参数2：返回值类型
    				ConvertUtils.register(new Converter() { 
    					
    					@Override
    					public <T> T convert(Class<T> clz, Object value) { 
    						// TODO Auto-generated method stub
    						//参数一：类型， 参数二：需要转换的值
    						SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd");
    						try { 
    							Date date=(Date) format.parse((String) value);//解析 解析字符串的文本，生成 Date。
    							return (T) date;
    						} catch (Exception e) { 
    							// TODO Auto-generated catch block
    							throw new RuntimeException("转换失败");
    						}				
    					}
    				}, Date.class);

# TestBeanUtil如下 #

package map2javabean;
    
    import java.beans.BeanInfo;
    import java.sql.Date;
    import java.text.ParseException;
    import java.text.SimpleDateFormat;
    import java.util.Map;
    
    import org.apache.commons.beanutils.BeanUtils;
    import org.apache.commons.beanutils.ConvertUtils;
    import org.apache.commons.beanutils.Converter;
    
    import TestIntrosPector.People;
    
    public class TestBeanUtil { 
    	public static void main(String[] args) throws Exception { 
    		//注册自定义转换器
    				//ConvertUtils.register(converter, clazz);
    				//参数1：转换器，参数2：返回值类型
    				ConvertUtils.register(new Converter() { 
    					
    					@Override
    					public <T> T convert(Class<T> clz, Object value) { 
    						// TODO Auto-generated method stub
    						//参数一：类型， 参数二：需要转换的值
    						SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd");
    						try { 
    							Date date=(Date) format.parse((String) value);//解析 解析字符串的文本，生成 Date。
    							return (T) date;
    						} catch (Exception e) { 
    							// TODO Auto-generated catch block
    							throw new RuntimeException("转换失败");
    						}				
    					}
    				}, Date.class);
    		//测试javabena2map
    		People peo=new People(1L,18, "王麻子", '男',null);
    		System.out.println(peo);		
    		Map<String, String> map=BeanUtils.describe(peo);//bena2map方法
    		System.out.println(map);
    		System.out.println("-------------------");
    		//测试map2javabena
    		//copy全部属性
    		People people=new People();
    		System.out.println(people);
    		
    		//BeanUtils.populate(people, map);//map2javabena方法
    		System.out.println(people);
    		System.out.println("-------------------");
    		/*将对象的属性信息copy到另外一个对象中去 copy全部属性*/
    		People people2=new People();
    		System.err.println(people2);
    		/*BeanUtils.copyProperties(dest, orig); dest:目标对象 orig:被copy的对象 orig可以是map */BeanUtils.copyProperties(people2, people);//copy方法
    		System.err.println("p2"+people2);
    		System.out.println("-------------------");	
    		//copy单个属性,也叫做给单个属性设置新值
    		BeanUtils.copyProperty(peo, "birday",new java.util.Date());
    		//BeanUtils.copyProperty(bean, name, value);
    		//bean:目标值 name：属性名：value：属性值
    		System.out.println(peo);
    		//获取单个指定属性以及它的值
    		String da=BeanUtils.getProperty(peo, "birday");
    		System.out.println(da);
    	}
    }

# 接下来看效果 #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDA1NjY2_size_16_color_FFFFFF_t_70 1]

# javabean People类源码如下 #

package TestIntrosPector;
    
    import java.util.Date;
    
    import lombok.AllArgsConstructor;
    import lombok.Data;
    import lombok.NoArgsConstructor;
    import lombok.ToString;
    
    @Data
    @AllArgsConstructor
    @NoArgsConstructor
    public class People { 
    	private long id;
    	private int age;
    	private String name;
    	private char sex='女';
    	private Date birday;
    }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDA1NjY2_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20190508212943859.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDA1NjY2,size_16,color_FFFFFF,t_70
[20190508213002127.png]: /images/20220203/bd0e742d3512439aa9a4552ec95213b6.png
[20190508213147724.png]: /images/20220203/f9d0f9a5ab35487dafc9126b9976a670.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQyNDA1NjY2_size_16_color_FFFFFF_t_70 1]: /images/20220203/01bc342f2c7d4d2e8cd594ca3c295fa1.png