XStream使用详解

class Person
{
	private String name;
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
	public String getName()
	{
		return name;
	}
	public void setName(String name)
	{
		this.name = name;
	}
	public int getAge()
	{
		return age;
	}
	public void setAge(int age)
	{
		this.age = age;
	}
	@Override
	public String toString()
	{
		return "Person [name=" + name + ", age=" + age + "]";
	}
}
public class PersonConverter implements Converter 
{
	@Override//定义转换器能转换的JavaBean类型
	public boolean canConvert(Class type)
	{
		return type.equals(Person.class);
	}
	@Override//把对象序列化成XML或Json
	public void marshal(Object value, HierarchicalStreamWriter writer, 
MarshallingContext context)
	{
		Person person = (Person) value;
        writer.startNode("姓名");
        writer.setValue(person.getName());
        writer.endNode();
        writer.startNode("年龄");
        writer.setValue(person.getAge()+"");
        writer.endNode();
        writer.startNode("转换器");
        writer.setValue("自定义的转换器");
        writer.endNode();
	}
	@Override//把XML或Json反序列化成对象
	public Object unmarshal(HierarchicalStreamReader reader, 
UnmarshallingContext context)
	{
		   Person person = new Person("",-1);
           reader.moveDown();
           person.setName(reader.getValue());
           reader.moveUp();
           reader.moveDown();
           person.setAge(Integer.parseInt(reader.getValue()));
           reader.moveUp();
           return person;
	}
}
public class Test
{
	public static void main(String[] args)
	{
		Person bean =new Person("张三",19);
		XStream xstream = new XStream();
		xstream.registerConverter(new PersonConverter());//注册转换器
		//序列化
		String xml = xstream.toXML(bean);
		System.out.println(xml);
		//反序列化
		bean=(Person)xstream.fromXML(xml);
		System.out.println(bean);
	}
}

<test.Person>
  <姓名>张三</姓名>
  <年龄>19</年龄>
  <转换器>自定义的转换器</转换器>
</test.Person>
Person [name=张三, age=19]

class Person
{
	private String name;
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
}
public class Test
{
	public static void main(String[] args) throws IOException
	{		
		XStream xstream = new XStream();
		ObjectOutputStream out = xstream.createObjectOutputStream(System.out);
		out.writeObject(new Person("张三",12));
		out.writeObject(new Person("李四",19));
		out.writeObject("Hello");
		out.writeInt(12345);
		out.close();
	}
}

<object-stream>
  <test.Person>
    <name>张三</name>
    <age>12</age>
  </test.Person>
  <test.Person>
    <name>李四</name>
    <age>19</age>
  </test.Person>
  <string>Hello</string>
  <int>12345</int>
</object-stream>

class Person
{
	private String name;
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
	@Override
	public String toString()
	{
		return "Person [name=" + name + ", age=" + age + "]";
	}
}
public class Test
{
	public static void main(String[] args) throws IOException, ClassNotFoundException
	{
		String s="<object-stream><test.Person><name>张三</name><age>12</age></test.Person><int>12345</int></object-stream>";
		StringReader reader = new StringReader(s);
		XStream xstream = new XStream();
		ObjectInputStream in = xstream.createObjectInputStream(reader);
		System.out.println((Person) in.readObject());
		System.out.println(in.readInt());
	}
}

Person [name=张三, age=12]
12345

7.Xstream持久化API

class Person
{
	private String name;
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
	@Override
	public String toString()
	{
		return "Person [name=" + name + ", age=" + age + "]";
	}
}
public class Test
{
	public static void main(String[] args) throws IOException, ClassNotFoundException
	{
		PersistenceStrategy strategy = new FilePersistenceStrategy(new File("D:\\tmp"));
		List list = new XmlArrayList(strategy);
		list.add(new Person("张三",13));//保存数据
		list.add(new Person("李四",21));
		list.add(new Person("王五",17));
	}
}

public class Test
{
	public static void main(String[] args) throws IOException, ClassNotFoundException
	{
		PersistenceStrategy strategy = new FilePersistenceStrategy(new File("D:\\tmp"));
		List list = new XmlArrayList(strategy);
		for (Iterator it = list.iterator(); it.hasNext();)
		{
			System.out.println((Person) it.next());
			it.remove();//删除对象序列化文件
		}
	}
}

Person [name=张三, age=13]
Person [name=李四, age=21]
Person [name=王五, age=17]

@XStreamAlias("人")
class Person
{
	@XStreamAlias("姓名")
	private String name;
	@XStreamAlias("年龄")
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
	@Override
	public String toString()
	{
		return "Person [name=" + name + ", age=" + age + "]";
	}
}
public class Test
{
	public static void main(String[] args)
	{
		Person bean=new Person("张三",19);
		XStream xstream = new XStream(new JettisonMappedXmlDriver());//设置Json解析器
		xstream.autodetectAnnotations(true);
		//Json序列化
		String xml = xstream.toXML(bean);
		System.out.println(xml);
		//Json反序列化
		bean=(Person)xstream.fromXML(xml);
		System.out.println(bean);
	}
}

{"人":{"姓名":"张三","年龄":19}}
Person [name=张三, age=19]

class Person
{
	private String name;
	private int age;
	public Person(String name, int age)
	{
		this.name = name;
		this.age = age;
	}
	@Override
	public String toString()
	{
		return "Person [name=" + name + ", age=" + age + "]";
	}
}
public class Test00
{
	public static void main(String[] args)
	{
		Person bean=new Person("张三",19);
		XStream xstream = new XStream(new JsonHierarchicalStreamDriver()
		{
			public HierarchicalStreamWriter createWriter(Writer writer)
			{
				return new JsonWriter(writer, JsonWriter.DROP_ROOT_MODE);
			}
		});
		//Json序列化
		String xml = xstream.toXML(bean);
		System.out.println(xml);
	}
}

{ "name": "张三", "age": 19 }