Apache组织开发了一套用于操作JavaBean的API，这套API考虑到了很多实际开发中的应用场景，因此在实际开发中很多程序员使用这套API操作JavaBean，以简化程序代码的编写。

BeanUtils的作用：

1）支持String到8种基本数据类型的转换；

2）其他引用数据类型都需要注册转换器：ConvertUtils.register(Converter,Class);

public class Person {    private String name;    private String password;    private Integer age;    private Date birthday;    getter/setter}

 

采用beanutils设置属性

@Testpublic void test1() throws Exception {    Person person = new Person();    BeanUtils.setProperty(person, "name", "zhangsan");    System.out.println(person.getName());}

 

采用beanutils拷贝对象的属性(基本类型)

@Testpublic void test2() throws Exception {    String name = "zhangsan";    String password = "123";    String age = "34";    Person person = new Person();    BeanUtils.setProperty(person, "name", name);    BeanUtils.setProperty(person, "password", password);    BeanUtils.setProperty(person, "age", age);// 自动类型转换，只支持8种基本数据类型    System.out.println(person);}

 

采用beanutils拷贝对象的属性(非基本类型)

@Testpublic void test3() throws Exception {    String name = "zhangsan";    String password = "123";    String age = "34";    String birthday = "1980-09-05";    Person person = new Person();    BeanUtils.setProperty(person, "name", name);    BeanUtils.setProperty(person, "password", password);    BeanUtils.setProperty(person, "age", age);// 自动类型转换    BeanUtils.setProperty(person, "birthday", birthday); // 类型转换失败    System.out.println(person);}

为让Date能够赋值到birthday属性上，我们给beanutils注册一个日期转换器。

改进代码如下：

@Testpublic void test4() throws Exception {    String name = "zhangsan";    String password = "123";    String age = "34";    String birthday = "1980-09-05";    ConvertUtils.register(new Converter() {        @Override        public Object convert(Class type, Object value) {            if (value == null) {                return null;            }            if (!(value instanceof String)) {                throw new ConversionException("只支持String类型的转换!");            }            String str = (String) value;            if (null == str || "".equals(str.trim())) {                return null;            }            SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");            try {                return format.parse(str);            } catch (ParseException e) {                throw new ConversionException(e);            }        }    }, Date.class);    Person person = new Person();    BeanUtils.setProperty(person, "name", name);    BeanUtils.setProperty(person, "password", password);    BeanUtils.setProperty(person, "age", age);// 自动类型转换    BeanUtils.setProperty(person, "birthday", birthday);     System.out.println(person);}

 

采用beanutils自带的日期类型转换器

@Testpublic void test5() throws Exception {    String name = "zhangsan";    String password = "123";    String age = "34";    String birthday = "1980-09-05";    ConvertUtils.register(new DateLocaleConverter(), Date.class);    Person person = new Person();    BeanUtils.setProperty(person, "name", name);    BeanUtils.setProperty(person, "password", password);    BeanUtils.setProperty(person, "age", age);// 自动类型转换    BeanUtils.setProperty(person, "birthday", birthday);     System.out.println(person);}

 

收集数据到map中，并通过beanutils拷贝到指定的对象中去

@Testpublic void test6() throws Exception {    Person person = new Person();    ConvertUtils.register(new DateLocaleConverter(), Date.class);    Map
     
       map = new HashMap
      
       ();    map.put("name", "aa");    map.put("password", "123");    map.put("age", 23);    map.put("birthday", "1980-09-05");    // 用map集合中的值，填充bean的属性，    // 注意：属性名称必须要一致    BeanUtils.populate(person, map);    System.out.println(person);}