1

このURLのSAXを使用してxml解析を作成したい

http://news.google.com/?output=rss

しかし、エラーが発生しました。どこで間違いを犯したか、または問題の別の解決策があるかどうかを確認して知らせてください。

この行でGoogleNewsSaxActivity.classにエラーが発生しました

for (int i = 0; i < baseParserData.getTitle().size(); i++) {

私のコードは以下の通りです。

GoogleNewsSaxActivity.class

public class GoogleNewsSaxActivity extends Activity {

BaseFeedParser baseParserData;

 ArrayList<HashMap<String, String>> items = new ArrayList<HashMap<String, String>>();
    private myAdapter rssadaptor = null;
    ListView lview;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    try {
        SAXParserFactory saxPF = SAXParserFactory.newInstance();
        SAXParser saxP = saxPF.newSAXParser();
        XMLReader xmlR = saxP.getXMLReader();


        URL url = new URL("http://news.google.com/?output=rss");                                                            

        RssHandler myXMLHandler = new RssHandler();
        xmlR.setContentHandler(myXMLHandler);

        xmlR.parse(new InputSource(url.openStream()));


    } catch (Exception e) {
        System.out.println(e);
    }

    baseParserData = RssHandler.baseParserData;

    /** 
     * Run a for loop to set All the TextViews with text until 
     * the size of the array is reached.
     * 
     **/
    for (int i = 0; i < baseParserData.getTitle().size(); i++) {

        System.out.println("value of i==============>" + i);
        HashMap<String, String> map = new HashMap<String, String>();

        map.put("title", baseParserData.getTitle().get(i));
        //map.put("Artist", baseParserData.getArtist().get(i));
        //map.put("Contry", baseParserData.getCountry().get(i));

        items.add(map);

        rssadaptor = new myAdapter(GoogleNewsSaxActivity.this, items);
    }

    lview = (ListView) findViewById(R.id.listView);

    // Getting adapter by passing xml data ArrayList
    rssadaptor = new myAdapter(this, items);
    lview.setAdapter(rssadaptor);

}
}

RssHandler.class

public class RssHandler extends DefaultHandler{

/*private List<BaseFeedParser> messages;
//private Message currentMessage;
private StringBuilder builder;*/


String elementValue = null;
Boolean elementOn = false;
public static BaseFeedParser baseParserData = null;

public static BaseFeedParser getBaseParserData() {

    return baseParserData;
}
public static void setBaseParserData(BaseFeedParser baseParserData) {

    RssHandler.baseParserData = baseParserData;
}

/*public List<BaseFeedParser> getMessages(){
    return this.messages;
}*/

@Override
public void startElement(String uri, String localName, String name,
        Attributes attributes) throws SAXException {
    elementOn = true;

    System.out.println("Hello this is startElement : =========>");

    if (localName.equals(BaseFeedParser.CHANNEL))
    {
        baseParserData = new BaseFeedParser();
    } else if (localName.equals(BaseFeedParser.ITEM)) {


    }
}

@Override
public void characters(char[] ch, int start, int length)
        throws SAXException {

    if (elementOn) {
        elementValue = new String(ch, start, length);
        elementOn = false;
    }

}


@Override
public void endElement(String uri, String localName, String qName)
        throws SAXException {

    elementOn = false;

    /** 
     * Sets the values after retrieving the values from the XML tags
     * */ 
    if (localName.equalsIgnoreCase(BaseFeedParser.TITLE))
        baseParserData.setTitle(elementValue);
    else if (localName.equalsIgnoreCase(BaseFeedParser.LINK))
        baseParserData.setLink(elementValue);
    else if (localName.equalsIgnoreCase(BaseFeedParser.PUB_DATE))
        baseParserData.setPubDate(elementValue);
    else if (localName.equalsIgnoreCase(BaseFeedParser.DESCRIPTION))
        baseParserData.setDescription(elementValue);

}


}

また、別の2つのクラスBaseFeedParser.classとmyAdapter.classがあります。BaseFeedParserクラスにはGetters / Settersメソッドが含まれ、myadapterはカスタムリストビューのアダプタークラスです。

ありがとう。

LOGCATにエラーを表示する

05-31 09:42:25.693: I/System.out(279): java.net.SocketException: Permission denied
05-31 09:42:25.713: D/AndroidRuntime(279): Shutting down VM
05-31 09:42:25.713: W/dalvikvm(279): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-31 09:42:25.752: E/AndroidRuntime(279): FATAL EXCEPTION: main
05-31 09:42:25.752: E/AndroidRuntime(279): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.rahul.android.sax/com.rahul.android.sax.GoogleNewsSaxActivity}: java.lang.NullPointerException
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread.access$2300(ActivityThread.java:125)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.os.Looper.loop(Looper.java:123)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-31 09:42:25.752: E/AndroidRuntime(279):  at java.lang.reflect.Method.invokeNative(Native Method)
05-31 09:42:25.752: E/AndroidRuntime(279):  at java.lang.reflect.Method.invoke(Method.java:521)
05-31 09:42:25.752: E/AndroidRuntime(279):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-31 09:42:25.752: E/AndroidRuntime(279):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-31 09:42:25.752: E/AndroidRuntime(279):  at dalvik.system.NativeStart.main(Native Method)
05-31 09:42:25.752: E/AndroidRuntime(279): Caused by: java.lang.NullPointerException
05-31 09:42:25.752: E/AndroidRuntime(279):  at com.rahul.android.sax.GoogleNewsSaxActivity.onCreate(GoogleNewsSaxActivity.java:61)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-31 09:42:25.752: E/AndroidRuntime(279):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
05-31 09:42:25.752: E/AndroidRuntime(279):  ... 11 more
4

1 に答える 1

1

そのために以下のコードを使用してください。

サイトリスト.java

public class SitesList {

    /** Variables */
    private ArrayList<String> name = new ArrayList<String>();
    private ArrayList<String> website = new ArrayList<String>();
    private ArrayList<String> pubdate = new ArrayList<String>();
    private ArrayList<String> desc = new ArrayList<String>();

    /**
     * In Setter method default it will return arraylist change that to add
     */

    public ArrayList<String> getName() {
        return name;
    }

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

    public ArrayList<String> getWebsite() {
        return website;
    }

    public void setWebsite(String website) {
        this.website.add(website);
    }

    public ArrayList<String> getPubdate() {
        return pubdate;
    }

    public void setPubdate(String pubdate) {
        this.pubdate.add(pubdate);
    }

    public ArrayList<String> getDesc() {
        return desc;
    }

    public void setDesc(String desc) {
        this.desc.add(desc);
    }

}

MyXMLHandler.java

public class MyXMLHandler extends DefaultHandler {

    Boolean currentElement = false;
    String currentValue = null;
    public static SitesList sitesList = null;

    public static SitesList getSitesList() {
        return sitesList;
    }

    public static void setSitesList(SitesList sitesList) {
        MyXMLHandler.sitesList = sitesList;
    }

    /**
     * Called when tag starts ( ex:- <name>AndroidPeople</name> -- <name> )
     */
    @Override
    public void startElement(String uri, String localName, String qName,
            Attributes attributes) throws SAXException {

        currentElement = true;

        if (localName.equals("channel")) {
            /** Start */
            sitesList = new SitesList();
        }

    }

    /**
     * Called when tag closing ( ex:- <name>AndroidPeople</name> -- </name> )
     */
    @Override
    public void endElement(String uri, String localName, String qName)
            throws SAXException {

        currentElement = false;

        /** set value */
        if (localName.equalsIgnoreCase("title")) {
            sitesList.setName(currentValue);
        } else if (localName.equalsIgnoreCase("link")) {
            sitesList.setWebsite(currentValue);
        } else if (localName.equalsIgnoreCase("pubDate")) {
            sitesList.setPubdate(currentValue);
        } else if (localName.equalsIgnoreCase("description")) {
            sitesList.setDesc(currentValue);
        }
    }

    /**
     * Called to get tag characters ( ex:- <name>AndroidPeople</name> -- to get
     * AndroidPeople Character )
     */
    @Override
    public void characters(char[] ch, int start, int length)
            throws SAXException {

        if (currentElement) {
            currentValue = new String(ch, start, length);
            currentElement = false;
        }

    }

}

MainActivity.java

public class MainActivity extends Activity {
    SitesList sitesList = null;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        /** Create a new layout to display the view */
        LinearLayout layout = new LinearLayout(this);
        layout.setOrientation(1);

        /** Create a new textview array to display the results */
        TextView name[];
        TextView website[];
        TextView pubdate[];
        TextView desc[];

        try {

            /** Handling XML */
            SAXParserFactory spf = SAXParserFactory.newInstance();
            SAXParser sp = spf.newSAXParser();
            XMLReader xr = sp.getXMLReader();

            /** Send URL to parse XML Tags */
            URL sourceUrl = new URL(
                    "http://news.google.com/?output=rss");

            /** Create handler to handle XML Tags ( extends DefaultHandler ) */
            MyXMLHandler myXMLHandler = new MyXMLHandler();
            xr.setContentHandler(myXMLHandler);
            xr.parse(new InputSource(sourceUrl.openStream()));

        } catch (Exception e) {
            System.out.println("XML Pasing Exception = " + e);
        }

        /** Get result from MyXMLHandler SitlesList Object */
        sitesList = MyXMLHandler.sitesList;

        /** Assign textview array lenght by arraylist size */
        name = new TextView[sitesList.getName().size()];
        website = new TextView[sitesList.getWebsite().size()];
        pubdate = new TextView[sitesList.getPubdate().size()];
        desc = new TextView[sitesList.getDesc().size()];

        System.out.println("Hello Name size is:- " +sitesList.getName().size());
        System.out.println("Hello website size is:- " +sitesList.getWebsite().size());
        System.out.println("Hello pubdate size is:- " +sitesList.getPubdate().size());
        System.out.println("Hello desc size is:- " +sitesList.getDesc().size());


        /** Set the result text in textview and add it to layout */
        for (int i = 0; i < sitesList.getName().size(); i++) {
            name[i] = new TextView(this);
            name[i].setText("Name is = " + sitesList.getName().get(i));
            website[i] = new TextView(this);
            website[i].setText("Link is = " + sitesList.getWebsite().get(i));

            layout.addView(name[i]);
            layout.addView(website[i]);
        }

        /** Set the result text in textview and add it to layout */
        for (int i = 0; i < sitesList.getPubdate().size(); i++) {
            pubdate[i] = new TextView(this);
            pubdate[i].setText("Pub date is = "
                    + sitesList.getPubdate().get(i));

            desc[i] = new TextView(this);
            desc[i].setText("Desc is = "
                    + sitesList.getDesc().get(i));

            layout.addView(pubdate[i]);
            layout.addView(desc[i]);
        }

        /** Set the layout view to display */
        setContentView(layout);

    }
}
于 2012-05-31T04:51:17.887 に答える