DocumentHelper和SAXReader解析XML字符串

﹏ヽ暗。殇╰゛Y 2022-08-21 01:04 249阅读 0赞

最近在看湖北中烟OA门户的项目，中烟门户里面解析XML文档使用的是**DocumentHelper**，之前做的智能导航项目里面解析XML使用的是**SAXReader**，很好奇它们有什么区别，于是就查资料将两者的用法简单总结了一下。

**SAXReader用法示例**

package com.eway.signature.action;
    
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.util.HashMap;
    import java.util.Iterator;
    import java.util.Map;
    import javax.servlet.ServletRequest;
    import javax.servlet.http.HttpServletRequest;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.dom4j.Document;
    import org.dom4j.DocumentException;
    import org.dom4j.DocumentHelper;
    import org.dom4j.Element;
    import org.dom4j.io.SAXReader;
    
    public class UploadFile{
        
    
        private static Log logger = LogFactory.getLog(UploadFile.class);
        //要上传的配置文件的路径
        static String uploadCfgFile = "WEB-INF/conf/uploadfile.xml";
        Document uploadDocument;//文档对象实体
        Map uploadMap = new HashMap();
    
        /**
         * 获取配置文件的绝对路径
         * @param request
         * @return
         */
        private String getUploadCfgFilePath(ServletRequest request){
            return ((HttpServletRequest) request).getSession().getServletContext().getRealPath("uploadCfgFile");
        }
    
        /**
         * 初始化配置文件
         * @param request
         * @return
         */
        private Document initUploadCfgDocument(ServletRequest request){
            SAXReader saxReader = new SAXReader();
            try {
                //得到指定文件，以流的形式对文件进行序列化
                FileInputStream fis = new FileInputStream(getUploadCfgFilePath(request));
                uploadDocument = (Document) saxReader.read(fis);
            } catch (FileNotFoundException e) {
                logger.debug(e);
            } catch (DocumentException e) {
                logger.debug(e);
            }
            return uploadDocument;
        }
    
        /**
         * 获取配置文件
         * @param request
         * @return
         */
        private Document getUploadCfgDocument(ServletRequest request){
            if (this.uploadDocument == null) {
                this.uploadDocument = initUploadCfgDocument(request);
            }
            return this.uploadDocument;
        }
    
        /**
         * 获取某个指定ticket节点的配置属性
         * @param request
         * @return
         */
        private Map getUploadMap(ServletRequest request){
    
            Document uploadDocument = getUploadCfgDocument(request);
            //得到XML的根节点(message)
            Element root = uploadDocument.getRootElement();
            Iterator tickets = root.element("body").element("ticketNotify").elementIterator();
            //获取ticketNotify节点下所有的ticket节点的配置属性，并将其放到Map中
            while (tickets.hasNext()) {
                Element ticket = (Element) tickets.next();
                uploadMap.put("id", ticket.attributeValue("id"));
                uploadMap.put("dealTime", ticket.attributeValue("dealTime"));
                uploadMap.put("status", ticket.attributeValue("status"));
            }
            //Element.asXML方法，获得包括该标签的所有XML数据
    //      System.out.println(root.element("body").asXML());
            return uploadMap;
        }
    }

**DocumentHelper的用法示例**

package com.eway.signature.action;
    
    import java.io.BufferedReader;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.util.HashMap;
    import java.util.Iterator;
    import java.util.Map;
    import javax.servlet.ServletRequest;
    import javax.servlet.http.HttpServletRequest;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.dom4j.Document;
    import org.dom4j.DocumentException;
    import org.dom4j.DocumentHelper;
    import org.dom4j.Element;
    
    public class UploadFile{
        
    
        private static Log logger = LogFactory.getLog(UploadFile.class);
        //要上传的配置文件的路径
        static String uploadCfgFile = "WEB-INF/conf/uploadfile.xml";
        Document uploadDocument;//文档对象实体
        Map uploadMap = new HashMap();
    
        /**
         * 获取配置文件的绝对路径
         * @param request
         * @return
         */
        private String getUploadCfgFilePath(ServletRequest request){
            return ((HttpServletRequest) request).getSession().getServletContext().getRealPath("uploadCfgFile");
        }
    
        /**
         * 获取配置文件
         * @param request
         * @return
         */
        private Document getUploadCfgDocument(ServletRequest request){
    
            String sText;
            StringBuffer sb = new StringBuffer();
            try {
                //得到指定文件，以流的形式对文件进行序列化
                BufferedReader br = new BufferedReader(
                        new InputStreamReader(new FileInputStream(getUploadCfgFilePath(request))));
                for (;;) {
                    sText = br.readLine();//一行一行的读取数据
                    if(sText == null){
                        break;
                    }
                    sb.append(sText);
                }
                uploadDocument = DocumentHelper.parseText(sb.toString());
            } catch (FileNotFoundException e) {
                logger.debug(e);
            } catch (DocumentException e) {
                logger.debug(e);
            } catch (IOException e) {
                logger.debug(e);
            }
            return uploadDocument;
        }
    
        /**
         * 获取某个指定ticket节点的配置属性
         * @param request
         * @return
         */
        private Map getUploadMap(ServletRequest request){
    
            Document document = getUploadCfgDocument(request);
            //获取根节点
            Element root = document.getRootElement();
            Iterator tickets = root.element("body").element("ticketNotify").elementIterator();
            //获取ticketNotify节点下所有的ticket节点的配置属性，并将其放到Map中
            while (tickets.hasNext()) {
                Element ticket = (Element) tickets.next();
                uploadMap.put("id", ticket.attributeValue("id"));
                uploadMap.put("dealTime", ticket.attributeValue("dealTime"));
                uploadMap.put("status", ticket.attributeValue("status"));
            }
            //Element.asXML方法，获得包括该标签的所有XML数据
    //      System.out.println(root.element("body").asXML());
            return uploadMap;
        }
    
    }

更多使用请参看DocumentHelper的在线API：

[http://dom4j.sourceforge.net/dom4j-1.6.1/apidocs/org/dom4j/DocumentHelper.html\#createAttribute%28org.dom4j.Element,%20org.dom4j.QName,%20java.lang.String%29][http_dom4j.sourceforge.net_dom4j-1.6.1_apidocs_org_dom4j_DocumentHelper.html_createAttribute_28org.dom4j.Element_20org.dom4j.QName_20java.lang.String_29]

SAXReader可以直接使用read()方法将一个文件输入流转换成Document对象；而DocumentHelper不能直接操作文件输入流，只能使用parseText()方法将string字符串解析成Document对象，所以必须先将文件输入流写到String字符串中，再由DocumentHelper去解析。

更多使用继续发现中~

[http_dom4j.sourceforge.net_dom4j-1.6.1_apidocs_org_dom4j_DocumentHelper.html_createAttribute_28org.dom4j.Element_20org.dom4j.QName_20java.lang.String_29]: http://dom4j.sourceforge.net/dom4j-1.6.1/apidocs/org/dom4j/DocumentHelper.html#createAttribute%28org.dom4j.Element,%20org.dom4j.QName,%20java.lang.String%29