XStream
1. 什么作用
* 可以把JavaBean转换为(序列化为)xml
2. XStream的jar包
* 核心JAR包:xstream-1.4.7.jar;
* 必须依赖包:xpp3_min-1.1.4c(XML Pull Parser,一款速度很快的XML解析器);
3. 使用步骤
* XStream xstream = new XStream();
* String xmlStr = xstream.toXML(javabean);
4. 使用细节
* 别名:把类型对应的元素名修改了
> xstream.alias("china", List.class):让List类型生成的元素名为china
> xstream.alias("province", Province.class):让Province类型生成的元素名为province
* 使用为属性:默认类的成员,生成的是元素的子元素!我们希望让类的成员生成元素的属性
> xstream.useAttributeFor(Province.class, "name"):把Province类的名为name成员,生成<province>元素的name属性
* 去除Collection类型的成名:我们只需要Collection的内容,而不希望Collection本身也生成一个元素
> xstream.addImplicitCollection(Province.class, "cities"):让Province类的名为cities(它是List类型的,它的内容还会生成元素)的成名不生成元素
* 去除类的指定成名,让其不生成xml元素
> xstream.omitField(City.class, "description"):在生成的xml中不会出现City类的名为description的对应的元素!
具体实例
[java] view plain copy
- package cn.itcast.demo1;
- import java.util.ArrayList;
- import java.util.List;
- import org.junit.Test;
- import com.thoughtworks.xstream.XStream;
- /**
- * 演示XStream
- * @author cxf
- *
- */
- public class Demo1 {
- // 返回javabean集合
- public List<Province> getProinvceList() {
- Province p1 = new Province();
- p1.setName("北京");
- p1.addCity(new City("东城区", "DongChengQu"));
- p1.addCity(new City("昌平区", "ChangPingQu"));
- Province p2 = new Province();
- p2.setName("辽宁");
- p2.addCity(new City("沈阳", "shenYang"));
- p2.addCity(new City("葫芦岛", "huLuDao"));
- List<Province> provinceList = new ArrayList<Province>();
- provinceList.add(p1);
- provinceList.add(p2);
- return provinceList;
- }
- /**
- <list> --> List类型显示list
- <cn.itcast.demo1.Province> --> javabean的类型为Province,它元素的名称为类的完整名
- <name>北京</name> --> javabean的属性名
- <cities> --> javabean的属性名
- <cn.itcast.demo1.City> --> 类名
- <name>东城区</name> --> 属性名
- <description>DongChengQu</description> --> 属性名
- </cn.itcast.demo1.City>
- <cn.itcast.demo1.City>
- <name>昌平区</name>
- <description>ChangPingQu</description>
- </cn.itcast.demo1.City>
- </cities>
- </cn.itcast.demo1.Province>
- <cn.itcast.demo1.Province>
- <name>辽宁</name>
- <cities>
- <cn.itcast.demo1.City>
- <name>沈阳</name>
- <description>shenYang</description>
- </cn.itcast.demo1.City>
- <cn.itcast.demo1.City>
- <name>葫芦岛</name>
- <description>huLuDao</description>
- </cn.itcast.demo1.City>
- </cities>
- </cn.itcast.demo1.Province>
- </list>
- */
- @Test
- public void fun1() {
- List<Province> proList = getProinvceList();
- /*
- * 创建XStream对象
- * 调用toXML把集合转换成xml字符串
- */
- XStream xstream = new XStream();
- String s = xstream.toXML(proList);
- System.out.println(s);
- }
- /*
- * 别名(alias)
- * 希望:
- * * 默认List类型对应<list>元素,希望让List类型对应<china>元素
- * * 默认Province类型对应<cn.itcast.demo1.Province>,希望让它对应<province>
- * * 默认City类型对应<cn.itcast.demo1.City>,希望它对应<city>元素
- */
- /*
- <china>
- <province>
- <name>北京</name>
- <cities>
- <city>
- <name>东城区</name>
- <description>DongChengQu</description>
- </city>
- <city>
- <name>昌平区</name>
- <description>ChangPingQu</description>
- </city>
- </cities>
- </province>
- <province>
- <name>辽宁</name>
- <cities>
- <city>
- <name>沈阳</name>
- <description>shenYang</description>
- </city>
- <city>
- <name>葫芦岛</name>
- <description>huLuDao</description>
- </city>
- </cities>
- </province>
- </china>
- */
- @Test
- public void fun2() {
- List<Province> proList = getProinvceList();
- XStream xstream = new XStream();
- /*
- * 给指定的类型指定别名
- */
- xstream.alias("china", List.class);//给List类型指定别名为china
- xstream.alias("province", Province.class);//给Province指定别名为province
- xstream.alias("city", City.class);//给City类型指定别名为city
- String s = xstream.toXML(proList);
- System.out.println(s);
- }
- /*
- * 默认javabean的属性都会生成子元素,而现在希望生成元素的属性
- */
- /*
- <china>
- <province name="北京">
- <cities>
- <city>
- <name>东城区</name>
- <description>DongChengQu</description>
- </city>
- <city>
- <name>昌平区</name>
- <description>ChangPingQu</description>
- </city>
- </cities>
- </province>
- <province name="辽宁">
- <cities>
- <city>
- <name>沈阳</name>
- <description>shenYang</description>
- </city>
- <city>
- <name>葫芦岛</name>
- <description>huLuDao</description>
- </city>
- </cities>
- </province>
- */
- @Test
- public void fun3() {
- List<Province> proList = getProinvceList();
- XStream xstream = new XStream();
- xstream.alias("china", List.class);//给List类型指定别名为china
- xstream.alias("province", Province.class);//给Province指定别名为province
- xstream.alias("city", City.class);//给City类型指定别名为city
- /*
- * 把Province类型的name属性,生成<province>元素的属性
- */
- xstream.useAttributeFor(Province.class, "name");
- String s = xstream.toXML(proList);
- System.out.println(s);
- }
- /*
- * 去除List类型的属性,只把list中的元素生成xml元素
- */
- /*
- <china>
- <province name="北京">
- <city>
- <name>东城区</name>
- <description>DongChengQu</description>
- </city>
- <city>
- <name>昌平区</name>
- <description>ChangPingQu</description>
- </city>
- </province>
- <province name="辽宁">
- <city>
- <name>沈阳</name>
- <description>shenYang</description>
- </city>
- <city>
- <name>葫芦岛</name>
- <description>huLuDao</description>
- </city>
- </province>
- </china>
- */
- @Test
- public void fun4() {
- List<Province> proList = getProinvceList();
- XStream xstream = new XStream();
- xstream.alias("china", List.class);//给List类型指定别名为china
- xstream.alias("province", Province.class);//给Province指定别名为province
- xstream.alias("city", City.class);//给City类型指定别名为city
- xstream.useAttributeFor(Province.class, "name");//把Province类型的name属性,生成<province>元素的属性
- /*
- * 去除<cities>这样的Collection类型的属性
- * 去除Provice类的名为cities的List类型的属性!
- */
- xstream.addImplicitCollection(Province.class, "cities");
- String s = xstream.toXML(proList);
- System.out.println(s);
- }
- /**
- * 去除不想要的javabean属性
- * 就是让某引起javabean属性,不生成对应的xml元素!
- */
- /*
- <china>
- <province name="北京">
- <city>
- <name>东城区</name>
- </city>
- <city>
- <name>昌平区</name>
- </city>
- </province>
- <province name="辽宁">
- <city>
- <name>沈阳</name>
- </city>
- <city>
- <name>葫芦岛</name>
- </city>
- </province>
- </china>
- */
- @Test
- public void fun5() {
- List<Province> proList = getProinvceList();
- XStream xstream = new XStream();
- xstream.alias("china", List.class);//给List类型指定别名为china
- xstream.alias("province", Province.class);//给Province指定别名为province
- xstream.alias("city", City.class);//给City类型指定别名为city
- xstream.useAttributeFor(Province.class, "name");//把Province类型的name属性,生成<province>元素的属性
- xstream.addImplicitCollection(Province.class, "cities");//去除Provice类的名为cities的List类型的属性!
- /*
- * 让City类的,名为description属性不生成对应的xml元素
- */
- xstream.omitField(City.class, "description");
- String s = xstream.toXML(proList);
- System.out.println(s);
- }
- }