淺析如何使用xstream實現(xiàn)javaBean與xml互轉(zhuǎn)

更新時間：2025年05月04日 08:47:57 作者：xuTao667

XStream 是一個用于將 Java 對象與 XML 之間進行轉(zhuǎn)換的庫,它非常簡單易用,下面將詳細介紹如何使用 XStream 實現(xiàn) JavaBean 與 XML 之間的互轉(zhuǎn),需要的可以了解下

1. 引入依賴

首先，確保在項目中引入了 XStream 的依賴。如果使用的是 Maven 構(gòu)建工具，可以在項目的 pom.xml 文件中添加如下依賴：

<dependency>
    <groupId>com.thoughtworks.xstream</groupId>
    <artifactId>xstream</artifactId>
    <version>1.4.19</version> <!-- 檢查是否有更新版本 -->
</dependency>

2. 定義 JavaBean

假設(shè)有一個簡單的 Person 類，包含姓名、年齡和地址信息：

public class Person {
    private String name;
    private int age;
    private Address address;
 
    // Getters and Setters
 
    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", address=" + address +
                '}';
    }
 
    public static class Address {
        private String street;
        private String city;
        private String state;
 
        // Getters and Setters
 
        @Override
        public String toString() {
            return "Address{" +
                    "street='" + street + '\'' +
                    ", city='" + city + '\'' +
                    ", state='" + state + '\'' +
                    '}';
        }
    }
}

3. JavaBean 轉(zhuǎn) XML

使用 XStream 將 Person 對象轉(zhuǎn)換為 XML 字符串：

import com.thoughtworks.xstream.XStream;
 
public class JavaBeanToXmlExample {
    public static void main(String[] args) {
        // 創(chuàng)建 Person 對象
        Person.Address address = new Person.Address();
        address.setStreet("123 Main St");
        address.setCity("Anytown");
        address.setState("Anystate");
 
        Person person = new Person();
        person.setName("John Doe");
        person.setAge(30);
        person.setAddress(address);
 
        // 創(chuàng)建 XStream 實例
        XStream xstream = new XStream();
 
        // 將 JavaBean 轉(zhuǎn)換為 XML
        String xml = xstream.toXML(person);
 
        // 輸出 XML
        System.out.println(xml);
    }
}

4. XML 轉(zhuǎn) JavaBean

使用 XStream 將 XML 字符串轉(zhuǎn)換為 Person 對象：

import com.thoughtworks.xstream.XStream;
 
public class XmlToJavaBeanExample {
    public static void main(String[] args) {
        // XML 字符串
        String xml = "<person>\n" +
                     "  <name>John Doe</name>\n" +
                     "  <age>30</age>\n" +
                     "  <address>\n" +
                     "    <street>123 Main St</street>\n" +
                     "    <city>Anytown</city>\n" +
                     "    <state>Anystate</state>\n" +
                     "  </address>\n" +
                     "</person>";
 
        // 創(chuàng)建 XStream 實例
        XStream xstream = new XStream();
 
        // 將 XML 轉(zhuǎn)換為 JavaBean
        Person person = (Person) xstream.fromXML(xml);
 
        // 輸出 JavaBean
        System.out.println(person);
    }
}

5. 自定義標簽名稱

默認情況下，XStream 會使用類名和字段名作為 XML 標簽名稱。如果想自定義標簽名稱，可以使用注解或配置方法。

使用注解

import com.thoughtworks.xstream.annotations.XStreamAlias;
 
@XStreamAlias("person")
public class Person {
    @XStreamAlias("full-name")
    private String name;
    @XStreamAlias("age-in-years")
    private int age;
    @XStreamAlias("address-info")
    private Address address;
 
    // Getters and Setters
 
    @Override
    public String toString() {
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", address=" + address +
                '}';
    }
 
    @XStreamAlias("address")
    public static class Address {
        @XStreamAlias("street-address")
        private String street;
        @XStreamAlias("city-name")
        private String city;
        @XStreamAlias("state-code")
        private String state;
 
        // Getters and Setters
 
        @Override
        public String toString() {
            return "Address{" +
                    "street='" + street + '\'' +
                    ", city='" + city + '\'' +
                    ", state='" + state + '\'' +
                    '}';
        }
    }
}

使用配置方法

import com.thoughtworks.xstream.XStream;
 
public class CustomTagExample {
    public static void main(String[] args) {
        // 創(chuàng)建 Person 對象
        Person.Address address = new Person.Address();
        address.setStreet("123 Main St");
        address.setCity("Anytown");
        address.setState("Anystate");
 
        Person person = new Person();
        person.setName("John Doe");
        person.setAge(30);
        person.setAddress(address);
 
        // 創(chuàng)建 XStream 實例
        XStream xstream = new XStream();
 
        // 配置自定義標簽名稱
        xstream.alias("person", Person.class);
        xstream.alias("address", Person.Address.class);
        xstream.aliasField("full-name", Person.class, "name");
        xstream.aliasField("age-in-years", Person.class, "age");
        xstream.aliasField("address-info", Person.class, "address");
        xstream.aliasField("street-address", Person.Address.class, "street");
        xstream.aliasField("city-name", Person.Address.class, "city");
        xstream.aliasField("state-code", Person.Address.class, "state");
 
        // 將 JavaBean 轉(zhuǎn)換為 XML
        String xml = xstream.toXML(person);
 
        // 輸出 XML
        System.out.println(xml);
    }
}

知識延展

使用xstream實現(xiàn)對象與XML互相轉(zhuǎn)換

依賴

       <dependency>
            <groupId>com.thoughtworks.xstream</groupId>
            <artifactId>xstream</artifactId>
            <version>1.4.18</version>
        </dependency>

實體類

package com.itheima.util;
 
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
 
@Data
@NoArgsConstructor
@AllArgsConstructor
public class Person {
    private String name;
    private int age;
}

工具類

package com.aircas.util;
 
import com.thoughtworks.xstream.XStream;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.StringWriter;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
 
public class XmlUtils {
 
    private static final XStream xStream = new XStream();
 
    static {
        // 允許反序列化
        xStream.allowTypesByWildcard(new String[] { "**" });
    }
 
    /**
     * 將 Java 對象轉(zhuǎn)換為 XML，并寫入指定文件。
     *
     * @param <T>     要轉(zhuǎn)換的 Java 對象類型
     * @param object  要轉(zhuǎn)換的 Java 對象
     * @param filePath 輸出的 XML 文件路徑
     */
    public static <T> void objectToXml(T object, String filePath) {
        // 為對象定義 XML 別名
        xStream.alias(object.getClass().getSimpleName(), object.getClass());
 
        StringWriter stringWriter = new StringWriter();
        stringWriter.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
 
        // 將對象轉(zhuǎn)為 XML 字符串
        xStream.toXML(object, stringWriter);
 
        // 獲取文件路徑
        Path path = Paths.get(filePath);
 
        // 使用 NIO 的 BufferedWriter 將 XML 字符串寫入文件
        try (BufferedWriter writer = Files.newBufferedWriter(path, StandardCharsets.UTF_8)) {
            writer.write(stringWriter.toString());
            System.out.println("XML 內(nèi)容已成功寫入到文件：" + path.toString());
        } catch (IOException e) {
            System.err.println("寫入 XML 文件時發(fā)生錯誤: " + e.getMessage());
            e.printStackTrace();
        }
    }
 
    /**
     * 從 XML 文件中讀取數(shù)據(jù)并轉(zhuǎn)換為 Java 對象。
     *
     * @param filePath XML 文件路徑
     * @param clazz    要轉(zhuǎn)換為的 Java 類
     * @param <T>      轉(zhuǎn)換后的對象類型
     * @return 轉(zhuǎn)換后的 Java 對象，如果讀取或轉(zhuǎn)換失敗則返回 null
     */
    public static <T> T xmlToObject(String filePath, Class<T> clazz) {
        Path path = Paths.get(filePath);
 
        // 驗證文件是否存在
        if (!Files.exists(path)) {
            System.err.println("指定的文件不存在: " + filePath);
            return null;
        }
 
        try {
            String xml = new String(Files.readAllBytes(path), StandardCharsets.UTF_8);
            xStream.alias(clazz.getSimpleName(), clazz); // 為目標類定義別名
            return (T) xStream.fromXML(xml); // 直接從 XML 字符串轉(zhuǎn)換
        } catch (IOException e) {
            System.err.println("讀取 XML 文件時發(fā)生錯誤: " + e.getMessage());
            e.printStackTrace();
        } catch (ClassCastException e) {
            System.err.println("轉(zhuǎn)換 XML 數(shù)據(jù)時發(fā)生錯誤: " + e.getMessage());
            e.printStackTrace();
        }
 
        return null;
    }
}

測試

package com.itheima.one;
 
import com.itheima.one.XmlUtils;
import com.itheima.util.Person;
 
public class Main {
    public static void main(String[] args) {
        // 假設(shè)有一個對象 person，你需要將其轉(zhuǎn)換為 XML
        Person person = new Person("John", 30);
        String filePath = "D:/Desktop/person.xml";
 
        // 調(diào)用靜態(tài)方法將對象轉(zhuǎn)換為 XML 并寫入文件
        XmlUtils.objectToXml(person, filePath);
 
        // 從 XML 文件中讀取并轉(zhuǎn)換為對象
        Person readPerson = XmlUtils.xmlToObject(filePath, Person.class);
        System.out.println(readPerson);
    }
}

輸出結(jié)果：

XML 內(nèi)容已成功寫入到文件：D:\Desktop\person.xml
Person(name=John, age=30)
D:/Desktop/person.xml文件內(nèi)容：
<?xml version="1.0" encoding="UTF-8"?>
<Person>
<name>John</name>
<age>30</age>
</Person>