XStream入门介绍3

Java 到xml，用toXML()方法。
Xml到Java，用fromXML()方法。
在没有任何设置默认情况下，java到xml的映 射，是java成员名对应xml的元素名，java类的全名对应xml根元素的名字。而实际中，往往是xml和java类都有了，要完成相互转换，必须进行别名映射。

eg 1:

package com.leadtone.util.xstream;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;
public class XstreamDemo {

	public static void main(String[] args) {
		XStream xstream = new XStream(new DomDriver());

		Person joe = new Person("Bill", "Gates");
		joe.setFaxNumber(new PhoneNumber(101, "83501194"));
		joe.setMobileNumber(new PhoneNumber(102, "13686447788"));

		String xml = xstream.toXML(joe);
		System.out.println(xml);
	}
}

 输出结果：

 

<com.leadtone.util.xstream.Person>
  <firstName>Bill</firstName>
  <lastName>Gates</lastName>
  <faxNumber>
    <phoneId>101</phoneId>
    <phoneNumber>83501194</phoneNumber>
  </faxNumber>
  <mobileNumber>
    <phoneId>102</phoneId>
    <phoneNumber>13686447788</phoneNumber>
  </mobileNumber>
</com.leadtone.util.xstream.Person>

 【注】：这里的最外层标签是<com.leadtone.util.xstream.Person>，而不是<Person>

eg 2：

package com.leadtone.util.xstream;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;

public class XstreamDemo {

	public static void main(String[] args) {
		
		XStream xstream = new XStream(new DomDriver());

		xstream.alias("person", Person.class);//映射

		Person joe = new Person("Bill", "Gates");
		joe.setFaxNumber(new PhoneNumber(101, "83501194"));
		joe.setMobileNumber(new PhoneNumber(102, "13686447788"));

		String xml = xstream.toXML(joe);
		System.out.println(xml);		
	}
}

 结果：

<person>
  <firstName>Bill</firstName>
  <lastName>Gates</lastName>
  <faxNumber>
    <phoneId>101</phoneId>
    <phoneNumber>83501194</phoneNumber>
  </faxNumber>
  <mobileNumber>
    <phoneId>102</phoneId>
    <phoneNumber>13686447788</phoneNumber>
  </mobileNumber>
</person>

 
别名配置包含三种情况：
1、类别名，用alias(String name, Class type)。
2、 类成员别名，用aliasField(String alias, Class definedIn, String fieldName)
3、 类成员作为属性别名，用 aliasAttribute(Class definedIn, String attributeName, String alias)，单独命名没有意义，还要通过useAttributeFor(Class definedIn, String fieldName) 应用到某个类上。

eg 3：

package com.leadtone.util.xstream;
import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;
public class XstreamDemo {

	public static void main(String[] args) {
		XStream xstream = new XStream(new DomDriver());

		xstream.alias("person", Person.class);
		xstream.aliasField("fn", Person.class,"firstName");
		xstream.aliasField("ln", Person.class,"lastName");

		Person joe = new Person("Bill", "Gates");
		joe.setFaxNumber(new PhoneNumber(101, "83501194"));
		joe.setMobileNumber(new PhoneNumber(102, "13686447788"));

		String xml = xstream.toXML(joe);
		System.out.println(xml);
	}
}

 输出结果：

<person>
  <fn>Bill</fn>
  <ln>Gates</ln>
  <faxNumber>
    <phoneId>101</phoneId>
    <phoneNumber>83501194</phoneNumber>
  </faxNumber>
  <mobileNumber>
    <phoneId>102</phoneId>
    <phoneNumber>13686447788</phoneNumber>
  </mobileNumber>
</person>

 eg 4：

 

package com.leadtone.util.xstream;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;

public class XstreamDemo {

	public static void main(String[] args) {
		
		XStream xstream = new XStream(new DomDriver());

		xstream.alias("person", Person.class);
		xstream.aliasField("fn", Person.class,"firstName");
		xstream.aliasField("ln", Person.class,"lastName");
		
		xstream.useAttributeFor(Person.class, "firstName"); //设置属性
		
		Person joe = new Person("Bill", "Gates");
		joe.setFaxNumber(new PhoneNumber(101, "83501194"));
		joe.setMobileNumber(new PhoneNumber(102, "13686447788"));

		String xml = xstream.toXML(joe);
		System.out.println(xml);
	}
}

 运行结果：

<person fn="Bill">
  <ln>Gates</ln>
  <faxNumber>
    <phoneId>101</phoneId>
    <phoneNumber>83501194</phoneNumber>
  </faxNumber>
  <mobileNumber>
    <phoneId>102</phoneId>
    <phoneNumber>13686447788</phoneNumber>
  </mobileNumber>
</person>

 
别名的配置是非常重要的，但是其中有些细节问题很重要，在例子中会专门做详细说明。
另外还有不太常用的方法：
addImplicitCollection(Class ownerType, String fieldName)，去掉集合类型生成xml的父节点。
registerConverter(Converter converter) ，注册一个转换器。

 

 

 

 

eg 5：把对象中的map映射为xml