I am trying to parse an XML file, but I am having some trouble fixing the errors I am receiving

Question

I have been trying to figure out how to figure out how I can solve the errors that I am receiving while trying to parse an XML file.

This is my MainActivity.java file:

package com.example.android;

import java.io.IOException;
import java.io.StringReader;
import java.io.UnsupportedEncodingException;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xmlpull.v1.XmlPullParser;

import android.R.string;
import android.app.Activity;
import android.os.Bundle;
import android.renderscript.Element;
import android.util.Log;
import android.view.Menu;
import android.view.Window;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;
import android.widget.TextView;

public class MainActivity extends Activity {

    String playerId,
           playerPd,
           playerType,
           xml;
    DefaultHttpClient httpClient;
    HttpPost httpPost;
    HttpResponse httpResponse;
    HttpEntity httpEntity;
    Document doc;
    DocumentBuilderFactory dbf;
    DocumentBuilder db;
    InputSource inputSource;
    NodeList n,
             nl;
    Node child;
    XmlPullParser parser;
    static final String URL = ".xml URL WITHELD";
    static final String PLAYERS = "Players"; //parent node
    static final String PLAYER_PD = "PlayerPD";
    static final String PLAYER_TYPE = "PlayerType";     

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //Remove title bar
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    public String getXmlFromUrl(String url){
        xml = null;
        try{
            //defaultHttpClient
            httpClient = new DefaultHttpClient();
            httpPost = new HttpPost (url);

            httpResponse = httpClient.execute(httpPost);
            httpEntity = httpResponse.getEntity();
            xml = EntityUtils.toString(httpEntity);         
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e){
            e.printStackTrace();
        }
        //return XML
        return xml; 
    }

    public Document getDomElement(String xml){
        doc = null;
        dbf = DocumentBuilderFactory.newInstance();
        try{
            db = dbf.newDocumentBuilder();

            inputSource = new InputSource();
            inputSource.setCharacterStream(new StringReader (xml)); 
            doc = db.parse(inputSource);
        } catch (ParserConfigurationException e) {
            Log.e("Error: ",e.getMessage());
            return null;
        } catch (SAXException e) {
            Log.e("Error: ",e.getMessage());
            return null;
        } catch (IOException e) {
            Log.e("Error: ",e.getMessage());
            return null;
        } 
        //return DOM
        return doc;     
    }

    public String getValue(Element item, String str){
        n = ((Document) item).getElementsByTagName(str);
        return this.getElementValue(n.item(0));     
    }

    private final String getElementValue(Node elem){
        // TODO Auto-generated method stub
        if(elem.hasChildNodes()){
            for(child = elem.getFirstChild(); child != null; child = child.getNextSibling()){
                if(child.getNodeType() == Node.TEXT_NODE){
                    return child.getNodeValue();
                }
            }
        }
        return null;        
    }


   public void parseXml(){

      xml = parser.getXmlFromUrl(URL); //Getting XML

On this line, Line 149, I receive an error that says"The method getXmlFromUrl(String) is undefined for the type XmlPullParser"

      doc = parser.getDomElement(xml); //Getting DOM element

And, on this line, Line 150, I receive an error that says, "The method getDomElement(String) is undefined for the type XmlPullParser"

      nl = doc.getElementsByTagName(PLAYERS);

      for (int i = 0; i < nl.getLength(); i++){
      playerPd = parser.getValue(e, PLAYER_PD); //PlayerPD child value

Also, on this line and the one that follows it, Lines 155 & 156, I receive an error that says, "e cannot be resolved to a variable"

      playerType = parser.getValue(e, PLAYER_TYPE); //Player Type child value
}

}
}

If this helps, the layout of the XML file I am trying to parse is like this:

-<Players>
  -<Player id="">
    <PlayerType></PlayerType>
   </Player>
 </Players>

Any help would be appreciated, and thanks in advance.

Answer 1

Remove parser.

public void parseXml(){

      xml = getXmlFromUrl(URL); //Getting XML

Or you can create a class XMLParser and add getXmlFromUrl function inside the new class

Similarly for other functions

doc = getDomElement(xml); //Getting DOM element

your lines 155 & 156 are not in the full source code so I'm not sure the context.

---

So you've mentioned the original tutorial. What the tutorial means is you need to create a new file XMLParser.java containing new class called XMLParser

public class XMLParser {
}

Then slowly you add functions to that class

public class XMLParser {
    public String getXmlFromUrl(String url) {
        String xml = null;

        try {
            // defaultHttpClient
            DefaultHttpClient httpClient = new DefaultHttpClient();
            HttpPost httpPost = new HttpPost(url);

            HttpResponse httpResponse = httpClient.execute(httpPost);
            HttpEntity httpEntity = httpResponse.getEntity();
            xml = EntityUtils.toString(httpEntity);

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        // return XML
        return xml;
    }
}

So on and so forth, adding the other functions to the class. Then you can use the class from your MainActivity class.

---

As for e cannot be resolved to a variable , there's a missing line in the web page.

NodeList nl = doc.getElementsByTagName(KEY_ITEM);

// looping through all item nodes <item>     
for (int i = 0; i < nl.getLength(); i++) {
    Element e = (Element)nl.item(i); // >>> the missing line in the sample <<<
    String name = parser.getValue(e, KEY_NAME); // name child value
    String cost = parser.getValue(e, KEY_COST); // cost child value
    String description = parser.getValue(e, KEY_DESC); // description child value
}