使用XStream是实现XML与Java对象的转换(5)--Object Stream

八，Object Stream

 之前的例子我们都是直接输出Xml成为String类型或者从String中获得并解析Xml，现在我们要处理输入流和输出流！

1,输出流(ObjectOutputStream)

输出流测试程序如下：

package cn.tjpu.zhw.xml.xstream5;

import java.io.IOException;
import java.io.ObjectOutputStream;

import com.thoughtworks.xstream.XStream;

public class OutMain {

   public static void main(String[] args) throws IOException {
      //创建XStream对象
      XStream xstream = new XStream();

      /*******1，序列化单个对象*******/
      System.out.println("*******1，序列化单个对象*******");
      xstream.toXML(new Person("张三"), System.out);

      System.out.println();
      System.out.println();

      /*******2，序列化一组对象*******/
      System.out.println("*******2，序列化一组对象*******");
      //将格式化后的xml输出到System.out中，root是根节点
      ObjectOutputStream oos = xstream.createObjectOutputStream(System.out,"root");
      oos.writeObject(new Person("张三"));
      oos.writeObject(new Person("李四"));
      oos.writeObject(new Integer(1));
      oos.writeObject(2);
      oos.writeObject(new Double(3));
      oos.writeObject(4d);
      oos.writeObject('c');
      oos.writeObject("这是一堆字符串！");
      //一定要关闭流
      oos.close();
   }
}

class Person {
   public Person(String name){
      this.name = name;
   }
   private String name;

   public String getName() {
      return name;
   }

   public void setName(String name) {
      this.name = name;
   }

   public String toString() {
      return "Person对象的name="+getName();
   }
}

运行结果：

*******1，序列化单个对象*******
<cn.tjpu.zhw.xml.xstream5.Person>
  <name>张三</name>
</cn.tjpu.zhw.xml.xstream5.Person>

*******2，序列化一组对象*******
<root>
  <cn.tjpu.zhw.xml.xstream5.Person>
    <name>张三</name>
  </cn.tjpu.zhw.xml.xstream5.Person>
  <cn.tjpu.zhw.xml.xstream5.Person>
    <name>李四</name>
  </cn.tjpu.zhw.xml.xstream5.Person>
  <int>1</int>
  <int>2</int>
  <double>3.0</double>
  <double>4.0</double>
  <char>c</char>
  <string>这是一堆字符串！</string>
</root>

 上面两个例子都是直接使用System.out，将XML输出到控制台。其实我们可以将其替换成我们喜欢的任何输出流，比如FileWriter等。

2,输入流(ObjectInputStream)

将如下内容写入D:/temp1.xml文件：

<cn.tjpu.zhw.xml.xstream5.Person>
  <name>张三</name>
</cn.tjpu.zhw.xml.xstream5.Person>

将如下内容写入D:/temp2.xml文件：

<root>
  <cn.tjpu.zhw.xml.xstream5.Person>
    <name>张三</name>
  </cn.tjpu.zhw.xml.xstream5.Person>
  <cn.tjpu.zhw.xml.xstream5.Person>
    <name>李四</name>
  </cn.tjpu.zhw.xml.xstream5.Person>
  <int>1</int>
  <int>2</int>
  <double>3.0</double>
  <double>4.0</double>
  <char>c</char>
  <string>这是一堆字符串！</string>
</root>

输入流测试程序如下：

package cn.tjpu.zhw.xml.xstream5;

import java.io.EOFException;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.ObjectInputStream;

import com.thoughtworks.xstream.XStream;

public class InMain {

   public static void main(String[] args) throws IOException, ClassNotFoundException {

      //创建XStream对象
      XStream xstream = new XStream();

      /*******1，反序列化一个对象*******/
      FileReader reader1 = new FileReader(new File("D:/temp1.xml"));
      Person pp = (Person)xstream.fromXML(reader1);
      System.out.println("*******1，反序列化一个对象*******");
      System.out.println("pp="+pp);


      System.out.println();
      System.out.println();

      /*******1，反序列化一组对象*******/
      FileReader reader2 = new FileReader(new File("D:/temp2.xml"));
      ObjectInputStream ois = xstream.createObjectInputStream(reader2);

      Person p1 = (Person)ois.readObject();
      System.out.println("p1="+p1);

      Person p2 = (Person)ois.readObject();
      System.out.println("p2="+p2);

      int i1 = (Integer)ois.readObject();
      System.out.println("i1="+i1);

      int i2 = (Integer)ois.readObject();
      System.out.println("i2="+i2);

      double d1 = (Double)ois.readObject();
      System.out.println("d1="+d1);

      double d2 = (Double)ois.readObject();
      System.out.println("d2="+d2);

      char ch = (Character)ois.readObject();
      System.out.println("ch="+ch);

      String str = (String)ois.readObject();
      System.out.println("str="+str);

      System.out.println("******异常捕获******");
      //发生异常
      try {
        ois.readObject();
      } catch (EOFException e) {
        System.out.println("因为已经没有数据了，再次读取时，就会发生EOFException异常");
      }
   }

}

运行结果：

*******1，反序列化一个对象*******
pp=Person对象的name=张三


p1=Person对象的name=张三
p2=Person对象的name=李四
i1=1
i2=2
d1=3.0
d2=4.0
ch=c
str=这是一堆字符串！
******异常捕获******
因为已经没有数据了，再次读取时，就会发生EOFException异常