XML操作類庫XStream使用詳解

更新時間：2023年11月15日 11:41:55 作者：spring_root

這篇文章主要給大家介紹了關(guān)于XML操作類庫XStream使用的相關(guān)資料,需要的朋友可以參考下

1.Xstream介紹

(1)Xstream介紹

Xstream是一種OXMapping 技術(shù)，是用來處理XML文件序列化的框架,在將JavaBean序列化，或?qū)ML文件反序列化的時候，不需要其它輔助類和映射文件，使得XML序列化不再繁索。Xstream也可以將JavaBean序列化成Json或反序列化，使用非常方便。

(2)Xstream的簡單例子

class Person//JavaBean實體類
{
    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)
    {
        Person bean=new Person("張三",19);
        XStream xstream = new XStream();
        //XML序列化
        String xml = xstream.toXML(bean);
        System.out.println(xml);
        //XML反序列化
        bean=(Person)xstream.fromXML(xml);
        System.out.println(bean);
        xstream = new XStream(new JettisonMappedXmlDriver());
        xstream.setMode(XStream.NO_REFERENCES);
        //Json序列化
        String json=xstream.toXML(bean);
        System.out.println(json);
        //Json反序列
        bean=(Person)xstream.fromXML(json);
        System.out.println(bean);
    }
}

注意： Xstream序列化XML時需要引用的jar包：xstream-[version].jar、xpp3-[version].jar、xmlpull-[version].jar。Xstream序列化Json需要引用的jar包：jettison-[version].jar。

使用Xstream序列化時，對JavaBean沒有任何限制。JavaBean的字段可以是私有的，也可以沒有g(shù)etter或setter方法，還可以沒有默認的構(gòu)造函數(shù)。

2.Xstream的基本使用

(1)Xstream序列化XML

Xstream序列化XML時可以允許用戶使用不同的XML解析器，用戶可以使用一個標(biāo)準的JAXP DOM解析器或自Java6集成StAX解析器。這樣用戶就不需要依賴xpp3-[version].jar。

Xstream序列化XML時，也可以對XML節(jié)點重命名。

public class Test
{
    public static void main(String[] args)
    {
        Person bean=new Person("張三",19);
        //XStream xstream = new XStream();//需要XPP3庫
        //XStream xstream = new XStream(new DomDriver());//不需要XPP3庫
        XStream xstream = new XStream(new StaxDriver());//不需要XPP3庫開始使用Java6
        xstream.alias("人",Person.class);//為類名節(jié)點重命名
        //XML序列化
        String xml = xstream.toXML(bean);
        System.out.println(xml);
        //XML反序列化
        bean=(Person)xstream.fromXML(xml);
        System.out.println(bean);
    }
}

(2)Xstream序列化Json

Xstream序列化Json與序列化XML類似，例如：

public class Test
{
    public static void main(String[] args)
    {
        Person bean=new Person("張三",19);
        XStream xstream = new XStream(new JettisonMappedXmlDriver());//設(shè)置Json解析器
        xstream.setMode(XStream.NO_REFERENCES);//設(shè)置reference模型,不引用
        xstream.alias("人",Person.class);//為類名節(jié)點重命名
        //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);
    }
}

3.Xstream序列化重命名

(1)為包重命名：Xstream.aliasPackage()方法

public class Test
{
    public static void main(String[] args)
    {
        Person bean=new Person("張三",19);
        XStream xstream = new XStream();
        xstream.aliasPackage("com.lzw", "test");//為包名稱重命名
        //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);
    }
}

(2)為類重命名：Xstream.alias()方法

public class Test
{
    public static void main(String[] args)
    {
        Person bean=new Person("張三",19);
        XStream xstream = new XStream();
        xstream.alias("人", Person.class);//為類名節(jié)點重命名
        //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);
    }
}

(3)為字段重命名：Xstream.aliasField()方法

public class Test
{
    public static void main(String[] args)
    {
        Person bean=new Person("張三",19);
        XStream xstream = new XStream();
        xstream.aliasField("姓名", Person.class,"name");//為類的字段節(jié)點重命名
        xstream.aliasField("年齡", Person.class,"age");//為類的字段節(jié)點重命名
        //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);
    }
}

(4)省略集合根節(jié)點：Xstream.addImplicitCollection()方法

class Person
{
    private String name;
    private int age;
    private List friends;
    public Person(String name, int age, String... friends)
    {
        this.name = name;
        this.age = age;
        this.friends = Arrays.asList(friends);
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", friends=" + friends + "]";
    }
}
public class Test
{
    public static void main(String[] args)
    {
        Person bean =new Person("張三",19,"李四","王五","趙六");
        XStream xstream = new XStream();
        xstream.addImplicitCollection(Person.class, "friends");//省略集合根節(jié)點
        //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);
    }
}

(5)把字段節(jié)點設(shè)置成屬性：Xstream.useAttributeFor()方法

public class Test
{
    public static void main(String[] args)
    {
        Person bean =new Person("張三",19,"李四","王五","趙六");
        XStream xstream = new XStream();
        xstream.useAttributeFor(Person.class, "name");//把字段節(jié)點設(shè)置成屬性
        //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);
    }
}

(6)隱藏字段：xstream.omitField()方

public class Test
{
    public static void main(String[] args)
    {
        Person bean =new Person("張三",19,"李四","王五","趙六");
        XStream xstream = new XStream();
        xstream.omitField(Person.class, "friends");//把字段節(jié)點隱藏
        //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);
    }
}

4.Xstream注解的使用

(1)設(shè)置Xstream應(yīng)用注解使用Xstream注解前需要對Xstream進行配置，可以使用兩種方式：應(yīng)用某個JavaBean類的注解或自動使用JavaBean類的注解。代碼如下：

XStream xstream = new XStream();
xstream.processAnnotations(Person.class);//應(yīng)用Person類的注解
xstream.autodetectAnnotations(true);//自動檢測注解

(2)重命名注解：@XStreamAlias()

@XStreamAlias("人")
class Person
{
    @XStreamAlias("姓名")
    private String name;
    @XStreamAlias("年齡")
    private int age;
    @XStreamAlias("朋友")
    private List friends;
    public Person(String name, int age, String... friends)
    {
        this.name = name;
        this.age = age;
        this.friends = Arrays.asList(friends);
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", friends=" + friends + "]";
    }
}

(3)省略集合根節(jié)點：@XStreamImplicit

class Person
{
    private String name;
    private int age;
    //@XStreamImplicit//只隱藏集合根節(jié)點
    @XStreamImplicit(itemFieldName="朋友")//設(shè)置重復(fù)的節(jié)點名，可能會導(dǎo)致無法反序列化
    private List<String> friends;
    public Person(String name, int age, String... friends)
    {
        this.name = name;
        this.age = age;
        this.friends = Arrays.asList(friends);
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", friends=" + friends + "]";
    }
}

(4)把字段節(jié)點設(shè)置成屬性：@XStreamAsAttribute

class Person
{
    @XStreamAsAttribute
    private String name;
    @XStreamAsAttribute
    private int age;
    private List<String> friends;
    public Person(String name, int age, String... friends)
    {
        this.name = name;
        this.age = age;
        this.friends = Arrays.asList(friends);
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", friends=" + friends + "]";
    }
}

(5)隱藏字段：@XStreamOmitField

class Person
{
    private String name;
    private int age;
    @XStreamOmitField
    private List<String> friends;
    public Person(String name, int age, String... friends)
    {
        this.name = name;
        this.age = age;
        this.friends = Arrays.asList(friends);
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", friends=" + friends + "]";
    }
}

(6)設(shè)置轉(zhuǎn)換器：@XStreamConverter()

class Person
{
    private String name;
    private int age;
    @XStreamConverter(value=BooleanConverter.class,booleans={false},strings={"男","女"})
    private boolean sex;
    public Person(String name, int age, boolean sex)
    {
        this.name = name;
        this.age = age;
        this.sex=sex;
    }
    @Override
    public String toString()
    {
        return "Person [name=" + name + ", age=" + age + ", sex=" + sex + "]";
    }
}

5.Xstream自定義的轉(zhuǎn)換器

(1)Xstream自帶的轉(zhuǎn)換器

Xstream內(nèi)部有許多轉(zhuǎn)換器，用于JavaBean對象到XML或Json之間的轉(zhuǎn)換。

這些轉(zhuǎn)換器的詳細信息網(wǎng)址：http://xstream.codehaus.org/converters.html

(2)使用自定義的轉(zhuǎn)換器

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//定義轉(zhuǎn)換器能轉(zhuǎn)換的JavaBean類型
    public boolean canConvert(Class type)
    {
        return type.equals(Person.class);
    }
    @Override//把對象序列化成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("年齡");
        writer.setValue(person.getAge()+"");
        writer.endNode();
        writer.startNode("轉(zhuǎn)換器");
        writer.setValue("自定義的轉(zhuǎn)換器");
        writer.endNode();
    }
    @Override//把XML或Json反序列化成對象
    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("張三",19);
        XStream xstream = new XStream();
        xstream.registerConverter(new PersonConverter());//注冊轉(zhuǎn)換器
        //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);
    }
}
}
}

(3)常用的轉(zhuǎn)換器接口與抽象類

SingleValueConverter：單值轉(zhuǎn)換接口
AbstractSingleValueConverter：單值轉(zhuǎn)換抽象類
Converter：常規(guī)轉(zhuǎn)換器接口

6.Xstream對象流的使用

(1)Xstream對象輸出流

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("張三",12));
        out.writeObject(new Person("李四",19));
        out.writeObject("Hello");
        out.writeInt(12345);
        out.close();
    }
}

注意： XStream對象流是通過標(biāo)準java.io.ObjectOutputStream和java.io.ObjectInputStream對象。因為XML文檔只能有一個根節(jié)點,必須包裝在一個序列化的所有元素額外的根節(jié)點。這個根節(jié)點默認 < object-stream >上面的例子所示。

(2)Xstream對象輸出流

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>張三</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());
    }
}
}

7.Xstream持久化API

(1)保存JavaBean對象

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("張三",13));//保存數(shù)據(jù)
        list.add(new Person("李四",21));
        list.add(new Person("王五",17));
    }
}

程序運行結(jié)果：如果我們檢查D:\tmp目錄,有三個文件:int@0.xml、int@1.xml、int@2.xml；每個對象都被序列化到XML文件里。

(2)讀取并刪除JavaBean對象

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();//刪除對象序列化文件
        }
    }
}

8.Xstream操作Json

(1)Xstream序列化Json的重命名

@XStreamAlias("人")
class Person
{
    @XStreamAlias("姓名")
    private String name;
    @XStreamAlias("年齡")
    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("張三",19);
        XStream xstream = new XStream(new JettisonMappedXmlDriver());//設(shè)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);
    }
}

注意： Xstream序列化Json的重命名的方式與其序列化成XML的方式一樣！

(2)去掉序列化Json的根節(jié)點

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("張三",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);
    }
}
}

注意： 去掉根節(jié)點后的Json串是不能反序列化的，因為XStream 不知道它的類型。