xStream之xml

1. 把对象进行字符串输出，把字符串作为对象读入

package org.frame.xstream;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;

import org.frame.xstream.dataobject.blog.Entry;

import com.thoughtworks.xstream.XStream;

public class TestObjectOutputStream {

	public static void main(String[] args) throws IOException, ClassNotFoundException {
		XStream xstream = new XStream(); 
		StringWriter someWriter = new StringWriter();
		ObjectOutputStream out = xstream.createObjectOutputStream(someWriter);
		out.writeObject(new Entry("Joe", "Walnes"));
		out.writeObject(new Entry("Someone", "Else"));
		out.writeObject("hello");
		out.writeInt(12345); 
		out.close();
		System.out.println(someWriter.toString());
		
		StringReader someReader = new StringReader(someWriter.toString());
		ObjectInputStream in = xstream.createObjectInputStream(someReader);

		Entry a = (Entry)in.readObject();
		Entry b = (Entry)in.readObject(); 
		String h = (String)in.readObject();
		int aa = in.readInt();
		System.out.println(a.title);
		System.out.println(a.description);
		System.out.println(b.title);
		System.out.println(b.description);
		System.out.println(h);
		System.out.println(aa);
	}
}

2. 把对象序列化到文件，和把文件反序列化为对象

package org.frame.xstream;

import java.util.Iterator;
import java.util.List;

import org.frame.xstream.dataobject.blog.Author;
import java.io.File;

import com.thoughtworks.xstream.persistence.FilePersistenceStrategy;
import com.thoughtworks.xstream.persistence.PersistenceStrategy;
import com.thoughtworks.xstream.persistence.XmlArrayList;

public class TestPersistence {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		//the E:/tmp must be exists
		PersistenceStrategy strategy = new FilePersistenceStrategy(new File("E:/tmp"));
		add(strategy);
		remove(strategy);
	}
	
	
	public static void add(PersistenceStrategy strategy ){
		// creates the list:
		List list = new XmlArrayList(strategy);
		
		// adds four authors
		list.add(new Author("joe walnes"));
		list.add(new Author("joerg schaible"));
		list.add(new Author("mauro talevi"));
		list.add(new Author("guilherme silveira"));
		
		// adding an extra author
		Author mistake = new Author("mama");
		list.add(mistake);
		//五个对象会生成五个文件 [email protected], [email protected], [email protected], [email protected], [email protected]
		//原来xstream生成全名的原因是为了序列化和反序列化.
	}
	
	public static void remove(PersistenceStrategy strategy){
		// looks up the list:
		List list = new XmlArrayList(strategy);
		
		// remember the list is still there! the files int@[1-5].xml are still in /tmp!
		// the list was persisted!
		
		for(Iterator it = list.iterator(); it.hasNext(); ) {
			Author author = (Author) it.next();
			if(author.getName().equals("mama")) {
				System.out.println("Removing mama...");
				it.remove();
			} else {
				System.out.println("Keeping " + author.getName());
			}
		}
	}

}

文件内容如下

<org.frame.xstream.dataobject.blog.Author>
  <name>mauro talevi</name>
</org.frame.xstream.dataobject.blog.Author>

其实这种方式挺好，比如会员登陆可以生成其登陆的基本信息，需要获取的时候，从文件系统反序列化读取，与数据库类似，但是存储的内容比较少，适合一般的场景，不需要数据库时[当然如果使用这种方式来实现数据库的API也不错啊，有时间研究研究，写测试用例的时候就可以更清晰了]
3. 把json转化为对象，和把对象生成对应的json

package org.frame.xstream;

import java.io.Writer;

import org.frame.xstream.dataobject.blog.Entry;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;
import com.thoughtworks.xstream.io.json.JsonHierarchicalStreamDriver;
import com.thoughtworks.xstream.io.json.JsonWriter;

/**
 * 其实使用返回的 { susccess: "true", errorMessage: "你长得太丑了" }
 * 
 * 可以使用对象形式，也可以建一个vm文件来维护返回的信息，推荐*.vm. 当然使用Action直接返回字符串，比拼凑的好玩点.
 * 
 * @author yangchunlong.tw
 * 
 */
public class TestWithJson {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		XStream xstream = createByJettison();
		jsonToObject(xstream);
	}

	public static void createJson(XStream xstream) {
		Entry product = new Entry("Banana", "123");
		xstream.setMode(XStream.NO_REFERENCES);
		xstream.alias("product", Entry.class);
		System.out.println(xstream.toXML(product));
		// 把xstream使用到json上也是相当给力的.

		// 这里都有一个对象名，还有一个不要根节点的
	}

	public static void jsonToObject(XStream xstream) {
		String json = "{\"product\":{\"title\":\"Banana\",\"description\":123}}";

		//XStream xstream = new XStream(new JettisonMappedXmlDriver());
		xstream.alias("product", Entry.class);
		Entry product = (Entry) xstream.fromXML(json);
		System.out.println(product.title);
		System.out.println(product.description);
	}

	public static XStream createByJettison() {
		return new XStream(new JettisonMappedXmlDriver());
	}

	public static XStream createByJDK() {
		// 不需要根节点，这个牛B了，不是接口也可以重写方法
		return new XStream(new JsonHierarchicalStreamDriver() {
			public HierarchicalStreamWriter createWriter(Writer writer) {
				return new JsonWriter(writer, JsonWriter.DROP_ROOT_MODE);
			}
		});
	}

}

4. 把对象转化为xml和把xml转化为对象

package org.frame.xstream;

import org.frame.xstream.dataobject.Person;
import org.frame.xstream.dataobject.PhoneNumber;

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

public class TestXStream {

	public static void main(String[] args) {
		//声名xstream
		XStream xstream = createByXPP3();
		xstream.alias("person", Person.class);
		xstream.alias("phonenumber", PhoneNumber.class);
		
		//组织对象
		Person joe = new Person("Joe", "Walnes");
		joe.setPhone(new PhoneNumber(123, "1234-456")); 
		
		//生成xml
		String xml = xstream.toXML(joe);
		System.out.println(xml);
		
		Person re = (Person) xstream.fromXML(xml);
		System.out.println(re.getFirstname());
		System.out.println(re.getLastname());
		System.out.println(re.getPhone().getCode());
		System.out.println(re.getPhone().getNumber());
		
	}
	
	/**
	 * XPP3. 
	 * 
	 * javax.xml.parsers.DocumentBuilderFactory
	 * @return
	 */
	public static XStream createByXPP3(){
		return  new XStream(); 
	}
	
	/**
	 * JAXP DOM parser 
	 * 
	 * javax.xml.parsers.DocumentBuilderFactory
	 * @return
	 */
	public static XStream createByDomDrive(){
		return  new XStream(new DomDriver()); 
	}
	
	/**
	 * Java 6 the integrated StAX parser
	 * <?xml version="1.0" ?>
	 * 
	 * @return
	 */
	public static XStream createByStax(){
		return  new XStream(new StaxDriver()); 
	}
	
	
}
5. 可以使用xstream高级有功能，使实体与xml名字不对应也能互转
package org.frame.xstream;

import org.frame.xstream.dataobject.Person;
import org.frame.xstream.dataobject.PhoneNumber;
import org.frame.xstream.dataobject.blog.Author;
import org.frame.xstream.dataobject.blog.AuthorConverter;
import org.frame.xstream.dataobject.blog.Blog;
import org.frame.xstream.dataobject.blog.Entry;

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

public class TestXStreamAlias {

	public static void main(String[] args) {
		
		Blog teamBlog = new Blog(new Author("Guilherme Silveira"));
        teamBlog.add(new Entry("first","My first blog entry."));
        teamBlog.add(new Entry("tutorial",
                "Today we have developed a nice alias tutorial. Tell your friends! NOW!"));

        XStream xstream = createByXPP3();
       // xstream.alias("blog", Blog.class);
       // xstream.alias("entry", Entry.class);//指定类的别包
       // xstream.aliasPackage("org.ycl", "org.frame");//改变包名
        xstream.processAnnotations(Blog.class);//启动Blog类的注解
        
        
       // xstream.useAttributeFor(Blog.class, "writer");//设置节点为属性
        xstream.aliasField("author", Blog.class, "writer");//指定类中属性的别名 
        xstream.processAnnotations(Entry.class);//启动Entry类的注解
        //如何把Anthor对象转化为String
        //xstream.registerConverter(new AuthorConverter());
       // xstream.addImplicitCollection(Blog.class, "entries");//不显示集合元素.
        String xml = xstream.toXML(teamBlog);
        System.out.println(xml); 
        
        Blog re = (Blog) xstream.fromXML(xml); 
        System.out.println(re.getContent());
        System.out.println(re.writer.getName());
	}
	
	/**
	 * XPP3. 
	 * 
	 * javax.xml.parsers.DocumentBuilderFactory
	 * @return
	 */
	public static XStream createByXPP3(){
		return  new XStream(); 
	}
	
	/**
	 * JAXP DOM parser 
	 * 
	 * javax.xml.parsers.DocumentBuilderFactory
	 * @return
	 */
	public static XStream createByDomDrive(){
		return  new XStream(new DomDriver()); 
	}
	
	/**
	 * Java 6 the integrated StAX parser
	 * <?xml version="1.0" ?>
	 * 
	 * @return
	 */
	public static XStream createByStax(){
		return  new XStream(new StaxDriver()); 
	}
	
	
}