使用 XStream 实现 Java 对象与 XML 的相互转换

1. 初始化要转为 XML 的数据：

// 生成第一条地址数据；Address address1 = new Address(1, "地址一", "广东省XX市", "XX公司");// 生成第二条地址数据；Address address2 = new Address(2, "地址二", "广东省XX市", "家");List<Address> addresses = new ArrayList<Address>();// 将生成的地址数据放到 List 中；addresses.add(address1);addresses.add(address2);// 生成 People 对象并制定相应数据；People people = new People(1, "Shawearn", 1, addresses);

2. Java 对象转化为 XML 格式的字符串：

// 新建 XStream 对象；XStream xStream = new XStream();// 将 People 类的示例转化为 XML 格式的字符串；String xmlStr = xStream.toXML(people);// 打印输出转化后的 XML 字符串；System.out.println(xmlStr);

运行结果

<com.shawearn.sitmap.People><id>1</id><name>Shawearn</name><age>1</age><addresses><com.shawearn.xml.Address><id>1</id><name>地址一</name><address>广东省XX市</address><desc>XX公司</desc></com.shawearn.xml.Address><com.shawearn.xml.Address><id>2</id><name>地址二</name><address>广东省XX市</address><desc>家</desc></com.shawearn.xml.Address></addresses></com.shawearn.xml.People>

我们会发现节点名字使用了类名，此时可以用 alias 指定 Java 类对应的节点名该方法需要在调用 toXML() 方法之前使用：

/** * Alias a Class to a shorter name to be used in XML elements. * * @param name Short name * @param type Type to be aliased * @throws InitializationException if no {@link ClassAliasingMapper} is available */public void alias(String name, Class type);

// 指定 People 类对应的节点名为 People；xStream.alias(People.class.getSimpleName(), People.class);// 指定 Address 类对应的节点名为 address；xStream.alias("address", Address.class);

指定别名后的运行结果：

<People><id>1</id><name>Shawearn</name><age>1</age><addresses><address><id>1</id><name>地址一</name><address>广东省XX市</address><desc>XX公司</desc></address><address><id>2</id><name>地址二</name><address>广东省XX市</address><desc>家</desc></address></addresses></People>

3. XML 转化为 Java 对象；

// 新建 XStream 对象；XStream s = new XStream();// 指定 People 类对应的节点名为 People；s.alias(People.class.getSimpleName(), People.class);// 指定 Address 类对应的节点名为 address；s.alias("address", Address.class);// 将 XML 字符串转化为 People 对象；People people2 = (People) s.fromXML(xmlStr);// 打印输出转化后的 People 对象；System.out.println(people2.toString());

运行结果：

People [id=1, name=Shawearn, age=1, addresses=[Address [id=1, name=地址一, address=广东省XX市, desc=XX公司], Address [id=2, name=地址二, address=广东省XX市, desc=家]]]