java - 如何解析URL中的xml文件

我尝试从此URL http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml获取货币。但是我的解析不起作用。这是我的代码。

http://www.ecb.europa.eu/stats/exchange/eurofxref/html/index.en.html

AndroidXMLParsingActivit.java

package com.androidhive.xmlparsing;

    import java.util.ArrayList;
    import java.util.HashMap;

    import org.w3c.dom.Document;
    import org.w3c.dom.Element;
    import org.w3c.dom.NodeList;

    import android.app.ListActivity;
    import android.content.Intent;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.AdapterView;
    import android.widget.AdapterView.OnItemClickListener;
    import android.widget.ListAdapter;
    import android.widget.ListView;
    import android.widget.SimpleAdapter;
    import android.widget.TextView;

    public class AndroidXMLParsingActivity extends ListActivity {

        // All static variables
        //static final String URL = "http://api.androidhive.info/pizza/?format=xml";
        static final String URL = "http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml";


        // XML node keys
        //static final String KEY_ITEM = "item"; // parent node
        static final String KEY_ITEM = "Cube"; // parent node

        static final String KEY_ID = "currency";
        static final String KEY_NAME = "rate";
        /*static final String KEY_ID = "id";
        static final String KEY_NAME = "name";
        static final String KEY_COST = "cost";
        static final String KEY_DESC = "description";*/

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

            ArrayList<HashMap<String, String>> menuItems = new ArrayList<HashMap<String, String>>();

            XMLParser parser = new XMLParser();
            String xml = parser.getXmlFromUrl(URL); // getting XML
            Document doc = parser.getDomElement(xml); // getting DOM element

            NodeList nl = doc.getElementsByTagName(KEY_ITEM);
            // looping through all item nodes <item>
            for (int i = 0; i < nl.getLength(); i++) {
                // creating new HashMap
                HashMap<String, String> map = new HashMap<String, String>();
                Element e = (Element) nl.item(i);
                // adding each child node to HashMap key => value
                map.put(KEY_ID, parser.getValue(e, KEY_ID));
                map.put(KEY_NAME, parser.getValue(e, KEY_NAME));
                //map.put(KEY_COST, "Rs." + parser.getValue(e, KEY_COST));
                //map.put(KEY_DESC, parser.getValue(e, KEY_DESC));

                // adding HashList to ArrayList
                menuItems.add(map);
            }

            // Adding menuItems to ListView
            ListAdapter adapter = new SimpleAdapter(this, menuItems,
                    R.layout.list_item,
                    //new String[] { KEY_NAME, KEY_DESC, KEY_COST }, new int[] {
                    new String[] { KEY_NAME, KEY_ID, KEY_ID }, new int[] {
                            R.id.name, R.id.desciption, R.id.cost });

            setListAdapter(adapter);

            // selecting single ListView item
            ListView lv = getListView();

            lv.setOnItemClickListener(new OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View view,
                        int position, long id) {
                    // getting values from selected ListItem
                    String name = ((TextView) view.findViewById(R.id.name)).getText().toString();
                    String cost = ((TextView) view.findViewById(R.id.cost)).getText().toString();
                    String description = ((TextView) view.findViewById(R.id.desciption)).getText().toString();

                    // Starting new intent
                    Intent in = new Intent(getApplicationContext(), SingleMenuItemActivity.class);
                    in.putExtra(KEY_ID, cost);
                    in.putExtra(KEY_NAME, name);

                    //in.putExtra(KEY_COST, cost);
                    //in.putExtra(KEY_DESC, description);
                    startActivity(in);

                }
            });
        }
    }

SingleMenuItemActivity.java

package com.androidhive.xmlparsing;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;

public class SingleMenuItemActivity  extends Activity {

    // XML node keys
    static final String KEY_ID = "currency";
    static final String KEY_NAME = "rate";

    /*static final String KEY_NAME = "name";
    static final String KEY_COST = "cost";
    static final String KEY_DESC = "description";*/
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.single_list_item);

        // getting intent data
        Intent in = getIntent();

        // Get XML values from previous intent
        String name = in.getStringExtra(KEY_NAME);
        String cost = in.getStringExtra(KEY_ID);
        /*String cost = in.getStringExtra(KEY_COST);
        String description = in.getStringExtra(KEY_DESC);*/

        // Displaying all values on the screen
        TextView lblName = (TextView) findViewById(R.id.name_label);
        TextView lblCost = (TextView) findViewById(R.id.cost_label);
        TextView lblDesc = (TextView) findViewById(R.id.description_label);

        lblName.setText(name);
        lblCost.setText(cost);
        lblDesc.setText(cost);

        Log.i("name", name+"");
        Log.i("cost", cost+"");
    }
}

XMLParser.java

package com.androidhive.xmlparsing;

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.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

import android.util.Log;

public class XMLParser {

    // constructor
    public XMLParser() {

    }

    /**
     * Getting XML from URL making HTTP request
     * @param url string
     * */
    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;
    }

    /**
     * Getting XML DOM element
     * @param XML string
     * */
    public Document getDomElement(String xml){
        Document doc = null;
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        try {

            DocumentBuilder db = dbf.newDocumentBuilder();

            InputSource is = new InputSource();
                is.setCharacterStream(new StringReader(xml));//
                doc = db.parse(is);

            } 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 doc;
    }

    /** Getting node value
      * @param elem element
      */
     public final String getElementValue( Node elem ) {
         Node child;
         if( elem != null){
             if (elem.hasChildNodes()){
                 for( child = elem.getFirstChild(); child != null; child = child.getNextSibling() ){
                     if( child.getNodeType() == Node.TEXT_NODE  ){
                         return child.getNodeValue();
                     }
                 }
             }
         }
         return "";
     }

     /**
      * Getting node value
      * @param Element node
      * @param key string
      * */
     public String getValue(Element item, String str) {
            NodeList n = item.getElementsByTagName(str);
            return this.getElementValue(n.item(0));
        }
}

最佳答案

here的原始帖子。

File fXmlFile = new File("your XML file");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(fXmlFile);

doc.getDocumentElement().normalize();

System.out.println("Root element :" + doc.getDocumentElement().getNodeName());

NodeList nList = doc.getElementsByTagName("Cube");

System.out.println("----------------------------");

for (int temp = 0; temp < nList.getLength(); temp++) {

    Node nNode = nList.item(temp);

    System.out.println("\nCurrent Element :" + nNode.getNodeName());


    if (nNode.getNodeType() == Node.ELEMENT_NODE) {

        Element eElement = (Element) nNode;
        String currency = eElement.getAttribute("currency");
        String rate = eElement.getAttribute("rate");
        if(currency.isEmpty()){
            continue;
        }
        System.out.println("Ccurrency :" + currency);
        System.out.println("Rate : " + rate);
    }
}

它正在打印货币和汇率。

关于java - 如何解析URL中的xml文件，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/24045207/