rssreader.java

基于J2ME的RSS阅读器

/*
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package pp.rss.reader.midlet;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.io.*;
import java.util.*;
import javax.microedition.rms.*;
import pp.rss.reader.ui.*;
import pp.rss.reader.model.RSSSourceEntry;
/**
 * @author Administrator
 */
public class RSSReader extends MIDlet implements CommandListener
{
    protected Display display;
    public List lsRSSSource;
    private Command cmdExit;
    private Command cmdAdd;
    private Command cmdEdit;
    private Command cmdDelete;
    public static final int MAX_RSS_SOURCE=15;
    public static final int MAX_RSS_LINK=75;
    public static final String[] DEFAULT_RSS_DESCRIPTIONS=
    {"ECommerce Times","Humorous Quotes",
     "Book Reviews","Slashdot.org","Web Developer"};
    public static final String[] DEFAULT_RSS_LINKS=
    {
        "http://www.ecommercetimes.com/perl/syndication/rssfull.pl",
        "http://www.quotationspage.com/data/qotd.rss",
        "http://p.moreover.com/cgi-local/page?index_bookreviews.rss",
        "http://slashdot.org/slashdot.rss",
        "http://headlines.internet.com/internetnews/wd-news/news.rss"
    };
    public Vector vecRSSSource;
    private RecordStore rsRSSSource;
    private static final String REC_STORE_RSS="RSSSource";
    public static final char SEPARATOR_CHAR='-';
    byte[] data=new byte[MAX_RSS_SOURCE+2+MAX_RSS_LINK];
    private AddForm fmAddRSSSource;
    private EditForm fmEditRSSSource;
    public TitleList lsShowHeadLines=null;
    private ArticleShowUI fmArticle;
    public InfoForm fmInfo;
    public RSSReader()
    {
        display=Display.getDisplay(this);
        cmdExit=new Command("退出程序",Command.EXIT,1);
        cmdAdd=new Command("添加RSS Feed源",Command.SCREEN,2);
        cmdEdit=new Command("编辑RSS Feed源",Command.SCREEN,2);
        cmdDelete=new Command("删除RSS Feed源",Command.SCREEN,2);
        vecRSSSource=new Vector();
        rsRSSSource=openRecordStore(REC_STORE_RSS);
        readRSSList();
        closeRecordStore(rsRSSSource);
        lsRSSSource=new List("RSS Feed列表",List.IMPLICIT);
        buildRSSList();
        lsRSSSource.addCommand(cmdExit);
        lsRSSSource.addCommand(cmdAdd);
        lsRSSSource.addCommand(cmdEdit);
        lsRSSSource.addCommand(cmdDelete);
        lsRSSSource.setCommandListener(this);
        
        fmAddRSSSource=new AddForm(this);
        fmEditRSSSource=new EditForm(this);
        fmArticle=new ArticleShowUI(this);
        fmInfo=new InfoForm(this);
    }
    public void startApp() 
    {
        showSourceForm();
    }

    public void pauseApp() 
    {
    }

    public void destroyApp(boolean unconditional) 
    {
        deleteRecordStore(REC_STORE_RSS);
        rsRSSSource=openRecordStore(REC_STORE_RSS);
        writeRSSList();
        closeRecordStore(rsRSSSource);
    }
    public void commandAction(Command command,Displayable displayable)
    {
        if(displayable==lsRSSSource&&command==List.SELECT_COMMAND)
        {
            if(lsShowHeadLines==null)
            {
                lsShowHeadLines=new TitleList(this);
            }
            RSSSourceEntry item=(RSSSourceEntry)vecRSSSource.elementAt(lsRSSSource.getSelectedIndex());
            lsShowHeadLines.getTitles(item.getLink());
            lsShowHeadLines.setTitle(item.getDescription());
            showHeadlines();
        }else if(command==cmdAdd)
        {
            showAddForm();
        }else if(command==cmdEdit)
        {
            if(lsRSSSource.size()>0)
            {
                int i=lsRSSSource.getSelectedIndex();
                RSSSourceEntry tmp=(RSSSourceEntry)vecRSSSource.elementAt(i);
                String desc=tmp.getDescription();
                String link=tmp.getLink();
                fmEditRSSSource.setDescription(desc);
                fmEditRSSSource.setLink(link);
                fmEditRSSSource.setIndex(i);
                showEditForm();
            }
        }else if(command==cmdDelete)
        {
            if(lsRSSSource.size()>1)
            {
                int i=lsRSSSource.getSelectedIndex();
                lsRSSSource.delete(i);
                vecRSSSource.removeElementAt(i);
            }else
            {
                fmInfo.setMessage("不能删除最后一个...");
            }
        }else if(command==cmdExit)
        {
            destroyApp(false);
            notifyDestroyed();
        }
    }
    public void add2Vector(String description,String link)
    {
        RSSSourceEntry item=new RSSSourceEntry(description,link.toLowerCase());
        vecRSSSource.insertElementAt(item, vecRSSSource.size());
    }
    public void showAddForm()
    {
        display.setCurrent(fmAddRSSSource);
    }
    public void showEditForm()
    {
        display.setCurrent(fmEditRSSSource);
    }
    public void showSourceForm()
    {
        display.setCurrent(this.lsRSSSource);
    }
    public void showInfoForm()
    {
        display.setCurrent(fmInfo);
    }
    public void showHeadlines()
    {
        display.setCurrent(lsShowHeadLines);
    }
    public void showArticleForm()
    {
        display.setCurrent(fmArticle);
    }
    public void setCurrent(Displayable displayable)
    {
        display.setCurrent(displayable);
    }
    private void deleteRecordStore(String name)
    {
        try
        {
            RecordStore.deleteRecordStore(name);
        }catch(Exception e)
        {
            debug(e.toString());
        }
    }
    private void closeRecordStore(RecordStore rs)
    {
        try
        {
            rs.closeRecordStore();
        }catch(Exception e)
        {
            debug(e.getMessage());
        }
    }
    private RecordStore openRecordStore(String name)
    {
        try
        {
            return RecordStore.openRecordStore(name, true);
        }catch(Exception e)
        {
            debug(e.toString());
            return null;
        }
    }
    public void writeRSSList()
    {
        try
        {
            ByteArrayOutputStream baos=new ByteArrayOutputStream();
            DataOutputStream dos=new DataOutputStream(baos);
            byte[] rsData;
            RSSSourceEntry item=null;
            String desc,link;
            for(int i=0;i<vecRSSSource.size();i++)
            {
                item=(RSSSourceEntry)vecRSSSource.elementAt(i);
                String tmp=item.getDescription()+SEPARATOR_CHAR+item.getLink();
                dos.writeUTF(tmp);
                dos.flush();
                rsData=baos.toByteArray();
                rsRSSSource.addRecord(rsData, 0, data.length);
                baos.reset();
            }
            baos.close();
            dos.close();
        }catch(Exception e)
        {
            debug(e.getMessage());
        }
    }
    private void readRSSList()
    {
        try
        {
            if(rsRSSSource.getNumRecords()<1)
            {
                int i=DEFAULT_RSS_DESCRIPTIONS.length;
                for(int j=0;j<i;j++)
                {
                    add2Vector(DEFAULT_RSS_DESCRIPTIONS[j],DEFAULT_RSS_LINKS[j]);
                }
                return;
            }
            ByteArrayInputStream bais=new ByteArrayInputStream(data);
            DataInputStream dis=new DataInputStream(bais);
            RSSSourceEntry item=null;
            String tmp_rms,tmp_parser;
            int offset;
            for(int i=1;i<rsRSSSource.getNumRecords();i++)
            {
                rsRSSSource.getRecord(i, data, 0);
                tmp_rms=dis.readUTF();
                offset=tmp_rms.indexOf(SEPARATOR_CHAR);
                item=new RSSSourceEntry(tmp_rms.substring(0, offset),tmp_rms.substring(offset+1, tmp_rms.length()));
                vecRSSSource.addElement(item);
                bais.reset();
            }
            bais.close();
            dis.close();
        }catch(Exception e)
        {
            debug(e.toString());
        }
    }
    private void buildRSSList()
    {
        RSSSourceEntry item=null;
        for(int i=0;i<vecRSSSource.size();i++)
        {
            item=(RSSSourceEntry)vecRSSSource.elementAt(i);
            lsRSSSource.append(item.getDescription(), null);
        }
    }
    public void debug(String message)
    {
        fmInfo.setMessage(message);
    }
    public void setArticleTitle(String title)
    {
        fmArticle.setArticleTitle(title);
    }
    public void setArticleContent(String content)
    {
        fmArticle.setArticleContent(content);
    }
}