Dom4J XStream 解析Xml

image

一、XStream的用途

     XStream是一个Java对象和XML相互转换的工具，很好很强大。提供了所有的基础类型、数组、集合等类型直接转换的支持。 

     因此XML常用于数据交换、对象序列化（这种序列化和Java对象的序列化技术有着本质的区别）。

    Stream对象相当Java对象和XML之间的转换器，转换过程是双向的。创建XSteam对象的方式很简单，只需要new XStream()即

     可。 
     Java到xml，用toXML()方法。 
     Xml到Java，用fromXML()方法。

废话不多说直接上例子

     <!--XStream依赖-->
        <dependency>
            <groupId>com.thoughtworks.xstream</groupId>
            <artifactId>xstream</artifactId>
            <version>1.4.9</version>
        </dependency>
        <!--dom4J依赖-->
        <dependency>
            <groupId>dom4j</groupId>
            <artifactId>dom4j</artifactId>
            <version>1.6.1</version>
        </dependency>

package test.com.wanggs.course.util;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.xml.DomDriver;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper;
import org.dom4j.Element;
import org.junit.Test;

import java.util.List;

/**
 * Created by wanggs on 2017/6/30.
 */
public class Dom4jAndXStreamTest {

    @Test
    // dom4j先热热身
    public void dom4j() throws DocumentException {
        //构造XML字符串
        StringBuffer stringBuffer = new StringBuffer();
        stringBuffer.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
        stringBuffer.append("<person>");
        stringBuffer.append("<name>ton</name>");
        stringBuffer.append("<sex>男</sex>");
        stringBuffer.append("<address>郑州市</address>");
        stringBuffer.append("</person>");

        System.out.println(stringBuffer.toString());

        //通过解析xml创建document对象
        Document document = DocumentHelper.parseText(stringBuffer.toString());
        //得到xml的根元素即(person)
        Element root = document.getRootElement();
        //得到根元素的所有子节点
        List<Element> elementList = root.elements();
        //遍历所有子节点
        for (Element element : elementList) {
            System.out.println(element.getName() + "=>>" + element.getText());
        }
    }

    /**
     * 输出结果：
     * name=>>ton
     * sex=>>男
     * address=>>郑州市
     */


    /**
     * java 对象装xml
     */
    @Test
    public void xStreamTest() {

        //构建Person对象
        Person person = new Person();
        person.setName("tom");
        person.setSex("男");
        person.setAddress("河南");

        /**
         * 对象转xml
         */
        XStream xStream = new XStream(new DomDriver());
        // 给Person定义别名
        xStream.alias("person", person.getClass());
        System.out.println(xStream.toXML(person));
        /**
         * 输出:
         * <person>
             <name>tom</name>
             <sex>男</sex>
             <address>河南</address>
             <outer-class/>
         </person>

         */
    }

    /**
     * xml装java对象
     */
    @Test
    public void xml2Java() {
        String xml = "<person><name>ton</name><sex>男</sex><address>河南</address></person>";
        XStream stream = new XStream(new DomDriver());
        stream.alias("person", Person.class);
        Person person = (Person) stream.fromXML(xml);
        System.out.println(person);

       //输出: Person{name='ton', sex='男', address='河南'}
    }

    //实体类,便于观看写在了一个类中
    class Person {
        private String name;
        private String sex;
        private String address;

        public String getName() {
            return name;
        }

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

        public String getSex() {
            return sex;
        }

        public void setSex(String sex) {
            this.sex = sex;
        }

        public String getAddress() {
            return address;
        }

        public void setAddress(String address) {
            this.address = address;
        }

        @Override
        public String toString() {
            return "Person{" +
                    "name='" + name + '\'' +
                    ", sex='" + sex + '\'' +
                    ", address='" + address + '\'' +
                    '}';
        }
    }
}

注解

package com.wanggs.xstream;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.annotations.XStreamAlias;
import com.thoughtworks.xstream.io.xml.DomDriver;

/**
 * Created by wanggs on 2017/7/28.
 */
@XStreamAlias("message")
public class RendezvousMessage {
    @XStreamAlias("type")
    private int messageType;

    public RendezvousMessage(int messageType) {
        this.messageType = messageType;
    }
}

class Tutorial {
    public static void main(String[] args) {
        XStream xStream = new XStream(new DomDriver());
        // 默认情况下XStream是不会扫描Annotations的
        xStream.processAnnotations(RendezvousMessage.class);
        
        RendezvousMessage rendezvousMessage = new RendezvousMessage(15);
        System.out.println(xStream.toXML(rendezvousMessage));

        /**
         * <message>
         <type>15</type>
         </message>

         */
    }
}

package com.kaishengit.course.util;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.core.util.QuickWriter;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.io.xml.PrettyPrintWriter;
import com.thoughtworks.xstream.io.xml.XppDriver;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import com.kaishengit.course.message.resp.*;

import javax.servlet.http.HttpServletRequest;
import java.io.InputStream;
import java.io.Writer;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 消息处理工具类
 * 
 * @author liufeng
 * @date 2013-09-15
 */
public class MessageUtil {
    // 请求消息类型：文本
    public static final String REQ_MESSAGE_TYPE_TEXT = "text";
    // 请求消息类型：图片
    public static final String REQ_MESSAGE_TYPE_IMAGE = "image";
    // 请求消息类型：语音
    public static final String REQ_MESSAGE_TYPE_VOICE = "voice";
    // 请求消息类型：视频
    public static final String REQ_MESSAGE_TYPE_VIDEO = "video";
    // 请求消息类型：地理位置
    public static final String REQ_MESSAGE_TYPE_LOCATION = "location";
    // 请求消息类型：链接
    public static final String REQ_MESSAGE_TYPE_LINK = "link";

    // 请求消息类型：事件推送
    public static final String REQ_MESSAGE_TYPE_EVENT = "event";

    // 事件类型：subscribe(订阅)
    public static final String EVENT_TYPE_SUBSCRIBE = "subscribe";
    // 事件类型：unsubscribe(取消订阅)
    public static final String EVENT_TYPE_UNSUBSCRIBE = "unsubscribe";
    // 事件类型：scan(用户已关注时的扫描带参数二维码)
    public static final String EVENT_TYPE_SCAN = "scan";
    // 事件类型：LOCATION(上报地理位置)
    public static final String EVENT_TYPE_LOCATION = "LOCATION";
    // 事件类型：CLICK(自定义菜单)
    public static final String EVENT_TYPE_CLICK = "CLICK";

    // 响应消息类型：文本
    public static final String RESP_MESSAGE_TYPE_TEXT = "text";
    // 响应消息类型：图片
    public static final String RESP_MESSAGE_TYPE_IMAGE = "image";
    // 响应消息类型：语音
    public static final String RESP_MESSAGE_TYPE_VOICE = "voice";
    // 响应消息类型：视频
    public static final String RESP_MESSAGE_TYPE_VIDEO = "video";
    // 响应消息类型：音乐
    public static final String RESP_MESSAGE_TYPE_MUSIC = "music";
    // 响应消息类型：图文
    public static final String RESP_MESSAGE_TYPE_NEWS = "news";

    /**
     * 解析微信发来的请求（XML）
     * 
     * @param request
     * @return Map<String, String>
     * @throws Exception
     */
    @SuppressWarnings("unchecked")
    public static Map<String, String> parseXml(HttpServletRequest request) throws Exception {
        // 将解析结果存储在HashMap中
        Map<String, String> map = new HashMap<String, String>();

        // 从request中取得输入流
        InputStream inputStream = request.getInputStream();
        // 读取输入流
        SAXReader reader = new SAXReader();
        Document document = reader.read(inputStream);
        // 得到xml根元素
        Element root = document.getRootElement();
        // 得到根元素的所有子节点
        List<Element> elementList = root.elements();

        // 遍历所有子节点
        for (Element e : elementList)
            map.put(e.getName(), e.getText());

        // 释放资源
        inputStream.close();
        inputStream = null;

        return map;
    }

    /**
     * 扩展xstream使其支持CDATA
     */
    private static XStream xstream = new XStream(new XppDriver() {
        public HierarchicalStreamWriter createWriter(Writer out) {
            return new PrettyPrintWriter(out) {
                // 对所有xml节点的转换都增加CDATA标记
                boolean cdata = true;

                @SuppressWarnings("unchecked")
                public void startNode(String name, Class clazz) {
                    super.startNode(name, clazz);
                }

                protected void writeText(QuickWriter writer, String text) {
                    if (cdata) {
                        writer.write("<![CDATA[");
                        writer.write(text);
                        writer.write("]]>");
                    } else {
                        writer.write(text);
                    }
                }
            };
        }
    });

    /**
     * 文本消息对象转换成xml
     * 
     * @param textMessage 文本消息对象
     * @return xml
     */
    public static String messageToXml(TextMessage textMessage) {
        xstream.alias("xml", textMessage.getClass());
        return xstream.toXML(textMessage);
    }

    /**
     * 图片消息对象转换成xml
     * 
     * @param imageMessage 图片消息对象
     * @return xml
     */
    public static String messageToXml(ImageMessage imageMessage) {
        xstream.alias("xml", imageMessage.getClass());
        return xstream.toXML(imageMessage);
    }

    /**
     * 语音消息对象转换成xml
     * 
     * @param voiceMessage 语音消息对象
     * @return xml
     */
    public static String messageToXml(VoiceMessage voiceMessage) {
        xstream.alias("xml", voiceMessage.getClass());
        return xstream.toXML(voiceMessage);
    }

    /**
     * 视频消息对象转换成xml
     * 
     * @param videoMessage 视频消息对象
     * @return xml
     */
    public static String messageToXml(VideoMessage videoMessage) {
        xstream.alias("xml", videoMessage.getClass());
        return xstream.toXML(videoMessage);
    }

    /**
     * 音乐消息对象转换成xml
     * 
     * @param musicMessage 音乐消息对象
     * @return xml
     */
    public static String messageToXml(MusicMessage musicMessage) {
        xstream.alias("xml", musicMessage.getClass());
        return xstream.toXML(musicMessage);
    }

    /**
     * 图文消息对象转换成xml
     * 
     * @param newsMessage 图文消息对象
     * @return xml
     */
    public static String messageToXml(NewsMessage newsMessage) {
        xstream.alias("xml", newsMessage.getClass());
        xstream.alias("item", new Article().getClass());
        return xstream.toXML(newsMessage);
    }
}

工具类

/**
     * 输出xml和解析xml的工具类
     *@ClassName:XmlUtil
     *@author: chenyoulong  Email: chen.youlong@payeco.com
     *@date :2012-9-29 上午9:51:28
     *@Description:TODO
     */
    public class XmlUtil{
        /**
         * java 转换成xml
         * @Title: toXml 
         * @Description: TODO 
         * @param obj 对象实例
         * @return String xml字符串
         */
        public static String toXml(Object obj){
            XStream xstream=new XStream();
//          XStream xstream=new XStream(new DomDriver()); //直接用jaxp dom来解释
//          XStream xstream=new XStream(new DomDriver("utf-8")); //指定编码解析器,直接用jaxp dom来解释
             
            ////如果没有这句，xml中的根元素会是<包.类名>；或者说：注解根本就没生效，所以的元素名就是类的属性
            xstream.processAnnotations(obj.getClass()); //通过注解方式的，一定要有这句话
            return xstream.toXML(obj);
        }
         
        /**
         *  将传入xml文本转换成Java对象
         * @Title: toBean 
         * @Description: TODO 
         * @param xmlStr
         * @param cls  xml对应的class类
         * @return T   xml对应的class类的实例对象
         * 
         * 调用的方法实例：PersonBean person=XmlUtil.toBean(xmlStr, PersonBean.class);
         */
        public static <T> T  toBean(String xmlStr,Class<T> cls){
            //注意：不是new Xstream(); 否则报错：java.lang.NoClassDefFoundError: org/xmlpull/v1/XmlPullParserFactory
            XStream xstream=new XStream(new DomDriver());
            xstream.processAnnotations(cls);
            T obj=(T)xstream.fromXML(xmlStr);
            return obj;         
        } 
 
       /**
         * 写到xml文件中去
         * @Title: writeXMLFile 
         * @Description: TODO 
         * @param obj 对象
         * @param absPath 绝对路径
         * @param fileName  文件名
         * @return boolean
         */
       
        public static boolean toXMLFile(Object obj, String absPath, String fileName ){
            String strXml = toXml(obj);
            String filePath = absPath + fileName;
            File file = new File(filePath);
            if(!file.exists()){
                try {
                    file.createNewFile();
                } catch (IOException e) {
                    log.error("创建{"+ filePath +"}文件失败!!!" + Strings.getStackTrace(e));
                    return false ;
                }
            }// end if 
            OutputStream ous = null ;
            try {
                ous = new FileOutputStream(file);
                ous.write(strXml.getBytes());
                ous.flush();
            } catch (Exception e1) {
                log.error("写{"+ filePath +"}文件失败!!!" + Strings.getStackTrace(e1));
                return false;
            }finally{
                if(ous != null )
                    try {
                        ous.close();
                    } catch (IOException e) {
                        log.error("写{"+ filePath +"}文件关闭输出流异常!!!" + Strings.getStackTrace(e));
                    }
            }
            return true ;
        }
         
        /**
         * 从xml文件读取报文
         * @Title: toBeanFromFile 
         * @Description: TODO 
         * @param absPath 绝对路径
         * @param fileName 文件名
         * @param cls
         * @throws Exception 
         * @return T
         */
        public static <T> T  toBeanFromFile(String absPath, String fileName,Class<T> cls) throws Exception{
            String filePath = absPath +fileName;
            InputStream ins = null ;
            try {
                ins = new FileInputStream(new File(filePath ));
            } catch (Exception e) {
                throw new Exception("读{"+ filePath +"}文件失败！", e);
            }
             
            String encode = useEncode(cls);
            XStream xstream=new XStream(new DomDriver(encode));
            xstream.processAnnotations(cls);
            T obj =null;
            try {
                obj = (T)xstream.fromXML(ins);
            } catch (Exception e) {
                // TODO Auto-generated catch block
                throw new Exception("解析{"+ filePath +"}文件失败！",e);
            }
            if(ins != null)
                ins.close();
            return obj;         
        } 
         
    }