BeanUtils总结

一、BeanUtils介绍

BeanUtils是apache的开发库；

为了使用BeanUtils，需要导入

(1)common-logging-1.1.1.jar

(2)common-beanutils.jar

 

二、BeanUtils开发

(1)设置属性；

(2)注册转换器；

(3)自定义转换器；

(4)批量设置属性；

注意：JavaBean必须是public的，不然BeanUtils会抛异常；

01 package org.xiazdong.beanutils;
02
03 import java.text.ParseException;
04 import java.text.SimpleDateFormat;
05 import java.util.Date;
06 import java.util.HashMap;
07 import java.util.Map;
08
09 import org.apache.commons.beanutils.BeanUtils;
10 import org.apache.commons.beanutils.ConversionException;
11 import org.apache.commons.beanutils.ConvertUtils;
12 import org.apache.commons.beanutils.Converter;
13 import org.apache.commons.beanutils.locale.converters.DateLocaleConverter;
14 import org.junit.Test;
15 import org.xiazdong.Person;
16
17 public class Demo01 {
18
19     // 设置属性
20     @Test
21     public void test1() throws Exception {
22         Person p = new Person();
23         BeanUtils.setProperty(p, "name", "xiazdong");
24         BeanUtils.setProperty(p, "age", 20);
25         System.out.println(p.getName());
26         System.out.println(p.getAge());
27     }
28
29     // 自定义转换器
30     @Test
31     public void test2() throws Exception {
32         Person p = new Person();
33         ConvertUtils.register(new Converter() {
34
35             @Override
36             public Object convert(Class type, Object value) {
37                 if (value == null) {
38                     return null;
39                 }
40                 if (!(value instanceof String)) {
41                     throw new ConversionException("conversion error");
42                 }
43                 String str = (String) value;
44                 if (str.trim().equals("")) {
45                     return null;
46                 }
47                 SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
48                 try {
49                     return sdf.parse(str);
50                 } catch (ParseException e) {
51                     throw new RuntimeException(e);
52                 }
53
54             }
55
56         }, Date.class);
57         BeanUtils.setProperty(p, "birth", "2011-10-10");
58         System.out.println(p.getBirth().toLocaleString());
59     }
60
61     // 使用内置的转换器
62     @Test
63     public void test3() throws Exception {
64         Person p = new Person();
65         ConvertUtils.register(new DateLocaleConverter(), Date.class);
66         BeanUtils.setProperty(p, "birth", "2011-10-10");
67         System.out.println(p.getBirth().toLocaleString());
68     }
69
70     // 使用内置的转换器
71     @Test
72     public void test4() throws Exception {
73         Map map = new HashMap();
74         map.put("name", "xiazdong");
75         map.put("age", "20");
76         map.put("birth", "2010-10-10");
77         ConvertUtils.register(new DateLocaleConverter(), Date.class);
78         Person p = new Person();
79         BeanUtils.populate(p, map);
80         System.out.println(p.getAge());
81         System.out.println(p.getBirth());
82     }
83 }