如何解析XML文件Java

Question

I'm trying to parse this XML file to get name . For example, "2b Managing the Non-Profit Organization".

I've tried to use DOM and xpath but I failed.

I'd like to loop through this xml and extract each song name. Here is my xpath example.

 XPath xPath = XPathFactory.newInstance().newXPath();
        NodeList nList = (NodeList)xPath.evaluate("/plist/dict/dict/dict/string[@rollno='artist']", root, XPathConstants.NODESET);
        for (int i = 0; i < nList.getLength(); ++i) {
            Element e = (Element) nList.item(i);
            String value = e.getFirstChild().getNodeValue();
        //   System.out.print("string:" + value+"");
            names_and_numbers.add( value); 
               System.out.print(names_and_numbers);

        }

Thanks

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict  rollno="393">
    <key>Major Version</key><integer>1</integer>
    <key>Minor Version</key><integer>1</integer>
    <key>Application Version</key><string>8.2.1</string>
    <key>Features</key><integer>5</integer>
    <key>Show Content Ratings</key><true/>
    <key>Music Folder</key><string>file://localhost/C:/WINNT/Profiles/A062616/My%20Documents/My%20Music/iTunes/iTunes%20Music/</string>
    <key>Library Persistent ID</key><string>542CEAB7C8BAE946</string>
    <key>Tracks</key>
    <dict>
        <key>124</key>
        <dict>
            <key>Track ID</key><integer>124</integer>
            <key>Name</key><string>2b Managing the Non-Profit Organization</string>
            <key>Artist</key><string>Peter Drucker</string>
            <key>Album</key><string>Managing the Non-Profit Organization</string>
            <key>Genre</key><string>AudioBook</string>
            <key>Kind</key><string>MPEG audio file</string>
            <key>Size</key><integer>15096591</integer>
            <key>Total Time</key><integer>2680320</integer>
            <key>Date Modified</key><date>2008-12-17T18:37:02Z</date>
            <key>Date Added</key><date>2008-12-17T17:36:38Z</date>
            <key>Bit Rate</key><integer>45</integer>
            <key>Sample Rate</key><integer>22050</integer>
            <key>Persistent ID</key><string>21B422A222B952AD</string>
            <key>Track Type</key><string>File</string>
            <key>Location</key><string>file://localhost/C:/WINNT/Profiles/A062616/My%20Documents/My%20Music/iTunes/iTunes%20Music/Peter%20Drucker/Managing%20the%20Non-Profit%20Organization/2b%20Managing%20the%20Non-Profit%20Organizat.mp3</string>
            <key>File Folder Count</key><integer>4</integer>
            <key>Library Folder Count</key><integer>1</integer>
        </dict>
        <key>126</key>
        <dict>
            <key>Track ID</key><integer>126</integer>
            <key>Name</key><string>1a Managing the Non-Profit Organization</string>
            <key>Artist</key><string>Peter Drucker</string>
            <key>Album</key><string>Managing the Non-Profit Organization</string>
            <key>Genre</key><string>AudioBook</string>
            <key>Kind</key><string>MPEG audio file</string>
            <key>Size</key><integer>16393005</integer>
            <key>Total Time</key><integer>2683402</integer>
            <key>Date Modified</key><date>2008-12-17T18:37:02Z</date>
            <key>Date Added</key><date>2008-12-17T17:36:38Z</date>
            <key>Bit Rate</key><integer>48</integer>
            <key>Sample Rate</key><integer>22050</integer>
            <key>Persistent ID</key><string>21B422A222B952AF</string>
            <key>Track Type</key><string>File</string>
            <key>Location</key><string>file://localhost/C:/WINNT/Profiles/A062616/My%20Documents/My%20Music/iTunes/iTunes%20Music/Peter%20Drucker/Managing%20the%20Non-Profit%20Organization/1a%20Managing%20the%20Non-Profit%20Organizat.mp3</string>
            <key>File Folder Count</key><integer>4</integer>
            <key>Library Folder Count</key><integer>1</integer>
        </dict>
        <key>128</key>
        <dict>
            <key>Track ID</key><integer>128</integer>
            <key>Name</key><string>1b Managing the Non-Profit Organization</string>
            <key>Artist</key><string>Peter Drucker</string>
            <key>Album</key><string>Managing the Non-Profit Organization</string>
            <key>Genre</key><string>AudioBook</string>
            <key>Kind</key><string>MPEG audio file</string>
            <key>Size</key><integer>16412357</integer>
            <key>Total Time</key><integer>2672195</integer>
            <key>Date Modified</key><date>2008-12-17T18:37:02Z</date>
            <key>Date Added</key><date>2008-12-17T17:36:38Z</date>
            <key>Bit Rate</key><integer>49</integer>
            <key>Sample Rate</key><integer>22050</integer>
            <key>Persistent ID</key><string>21B422A222B952B0</string>
            <key>Track Type</key><string>File</string>
            <key>Location</key><string>file://localhost/C:/WINNT/Profiles/A062616/My%20Documents/My%20Music/iTunes/iTunes%20Music/Peter%20Drucker/Managing%20the%20Non-Profit%20Organization/1b%20Managing%20the%20Non-Profit%20Organizat.mp3</string>
            <key>File Folder Count</key><integer>4</integer>
            <key>Library Folder Count</key><integer>1</integer>
        </dict> 
      </dict>
   </dict>
</plist>

Answer 1

Try this XPath expression instead:

/plist/dict/dict/dict/key[text()='Name']/following::string[1]

This will select the first string following a key with text Name

public static void main(String[] args) {
  try {
    InputSource root = new InputSource(XMLParse.class.getResourceAsStream("/data.xml"));
      XPath xPath = XPathFactory.newInstance().newXPath();
      NodeList nList = (NodeList)xPath.evaluate("/plist/dict/dict/dict/key[text()='Name']/following::string[1]", root, XPathConstants.NODESET);
      for (int i = 0; i < nList.getLength(); ++i) {
          Element e = (Element) nList.item(i);
          String value = e.getFirstChild().getNodeValue();

          System.out.println("string:" + value+"");

      }
 }  catch (XPathExpressionException e) {

    e.printStackTrace();
 } catch (DOMException e) {

    e.printStackTrace();
 }
}