rssfeedgui.java

RssFeed阅读器,可以任意加入删除管理任何RSS FEED,采用多性程打开你所关注的新闻内容。

				return addr.substring(lastSlashIndex + 1, lastQuestionIndex);
			else
				return null;
		}
	}
	
	/**
	 * obtain file name from URL format input
	 * @param addr
	 * 		URL format string
	 * @return
	 * 		web file
	 */
	public String getFilenameFromURLFormat(String addr) {
		int lastSlashIndex = addr.lastIndexOf('/');
		if (lastSlashIndex >= 0 &&
		    lastSlashIndex < addr.length() - 1) {
			return addr.substring(lastSlashIndex + 1);
		}
		else
			return null;
	}
	
	/**
	 * Implements a ListSelectionListener for making the UI respond when a
	 * different feed is selected from the list.
	 */
	private class FeedListListener implements ListSelectionListener {
		
		/**
     	* @see javax.swing.event.ListSelectionListener#valueChanged(javax.swing.event.ListSelectionEvent)
     	*/
		public void valueChanged(ListSelectionEvent e) {
	    	if (feedNameList.getSelectedValue() != null
	        	&& !feedNameList.getSelectedValue().equals("")) {
	    		clearLinkPaneElements();
	    		getItemList((String)feedNameList.getSelectedValue());
	    	}
	    }
		
		/**
		 * obtain feed item list by feed name
		 * @param feedname
		 * 		the selected feed name
		 */
		public void getItemList( String feedname ) {
			
			RssFeedXMLDataSource getfeedXml = new RssFeedXMLDataSource();

			data.get(getfeedXml, feedname);
		}
	}


	/**
	 * Implements a ListSelectionListener for making the UI respond when a
	 * different item is selected from the list.
	 */
	private class ItemListListener implements ListSelectionListener {

		/**
     	* @see javax.swing.event.ListSelectionListener#valueChanged(javax.swing.event.ListSelectionEvent)
     	*/
		public void valueChanged(ListSelectionEvent e) {
	    	if (feedItemList.getSelectedValue() != null
	        	&& !feedItemList.getSelectedValue().equals("")) 
	    		getOneItem((String)feedItemList.getSelectedValue());
	    }
		
		/**
		 * obtain one item details by item name
		 * @param itemname
		 * 		the selected one item
		 */
		public void getOneItem( String itemname ) {
			String feedname;
			RssFeedItem feedItem;
			
			feedname = (String)feedNameList.getSelectedValue();
			RssFeedXMLDataSource getItemXml = new RssFeedXMLDataSource();

    		feedItem = data.getItem(getItemXml, feedname, itemname);
    		showItem( feedItem );
		}
	}
	
	/**
	 * show the item title, link, pubDate, description and article of the item
	 * @param feedItem
	 * 		feed item object
	 */
	public void showItem(RssFeedItem feedItem) {
		String file;
		
		feedTitleTxt.setText(feedItem.getItemTitle());
		feedLinkTxt.setText(feedItem.getItemlink());
		feedDateTxt.setText(feedItem.getItemPubDate());
		feedDescTxt.setText(feedItem.getItemDescription());

		feedDescTxt.setLineWrap(true);
		feedDescTxt.setWrapStyleWord(true);
		
		file = getFilenameFromLinkField(feedLinkTxt.getText());
		
		/**
		 * check the item is cached, if yes get the content from cache,or
		 * Start a thread to obtain item description form downloaded file
		 * and cache the content. 
		 */
		if(saveArticleMap.containsKey(feedLinkTxt.getText()))
			htmlLabel.setText(saveArticleMap.get(feedLinkTxt.getText()));
		else {
			htmlLabel.setText("");
			new Thread(new RssFeedItemReader(feedLinkTxt.getText(), file)).start();
		}
	}
	
	/**
	 * check the source string include the pattern string
	 * @param source
	 * 		the source string
	 * @param pattern
	 * 		the pattern string
	 * @return
	 * 		true/false
	 */
	public boolean patternMatch(String source, String pattern) {
		
		Pattern p = Pattern.compile(pattern);
		Matcher m = p.matcher(source);
		if(m.find())
			return true;
		else
			return false;
	}
	

	/**
	 * Rss feed file download runnable class
	 * 
	 * @author Jack
	 *
	 */
	public class RssFeedDownload implements Runnable {
		
		private String addr;
		
		/**
		 * @param addr
		 */
		public RssFeedDownload(String addr){
			this.addr = addr;
		}
		
		/* (non-Javadoc)
		 * @see java.lang.Runnable#run()
		 */
		@Override
		public void run() {
			String file;
			String xml;
			
			OutputStream out = null;
			URLConnection conn = null;
			InputStream  in = null;
			file = getFilenameFromURLFormat(addr);
			
			if(file == null) {
				JOptionPane.showMessageDialog(frameDialog,
	                 "Input format error !\n( Example: http://feeds.news.com.au/rss/news.xml )",
	                 "Add new feed",
	                 JOptionPane.ERROR_MESSAGE);
				return;
			}

			try {
				URL url = new URL(addr);
				out = new BufferedOutputStream(
						new FileOutputStream(file));

				conn = url.openConnection();
				in = conn.getInputStream();
				byte[] buffer = new byte[1024];
				int numRead;
				long numWritten = 0;
				while ((numRead = in.read(buffer)) != -1) {
					out.write(buffer, 0, numRead);
					numWritten += numRead;
				}
			} catch (Exception exception) {
				JOptionPane.showMessageDialog(frameDialog, 
						"NetWork connection error !", 
						"Add new feed", 
						JOptionPane.ERROR_MESSAGE);

				exception.printStackTrace();
				return;
			}finally {
				try {
					if (in != null) {
						in.close();
					}
					if (out != null) {
						out.close();
					}
				} catch (IOException ioe) {
				}
			}
			xml = getFilenameFromURLFormat(addr);
			if(xml != null) {
				RssFeedXMLDataSource addfeedmxl = new RssFeedXMLDataSource(xml);
				data.add(addfeedmxl);
			}
			else {
				return;
			}
			//delete temporary file
			File temFile = new File(xml);
			if(temFile.exists())
				temFile.delete();
			
	    	feedNameTxt.setText("");
		}
	}
	
	/**
	 * Rss feed item web page download and the article pick up runnable class
	 * 
	 * @author Jack
	 *
	 */
	public class RssFeedItemReader implements Runnable {

		private String urlPara;
		private String localname;
		
		public RssFeedItemReader() {
			
		}

		/**
		 * constructor for the class
		 * @param urlPara
		 * 		URL format string
		 * @param localname
		 * 		web file name
		 */
		public RssFeedItemReader(String urlPara, String localname) {
			super();
			this.urlPara = urlPara;
			this.localname = localname;
		}

		/* (non-Javadoc)
		 * @see java.lang.Runnable#run()
		 */
		@Override
		public void run() {
			String file;
			
			OutputStream out = null;
			URLConnection conn = null;
			InputStream  in = null;
			file = getFilenameFromURLFormat(urlPara);
			if(file == null) {
		   		 JOptionPane.showMessageDialog(null,
	                 "Input format error !\n( Example: http://feeds.news.com.au/rss/news.xml )",
	                 "Add new feed",
	                 JOptionPane.ERROR_MESSAGE);
			}

			try {
				URL url = new URL(urlPara);
				out = new BufferedOutputStream(new FileOutputStream(localname));
				conn = url.openConnection();
				in = conn.getInputStream();
				byte[] buffer = new byte[1024];
				int numRead;
				long numWritten = 0;
				while ((numRead = in.read(buffer)) != -1) {
					out.write(buffer, 0, numRead);
					numWritten += numRead;
				}
			} catch (Exception exception) {
				JOptionPane.showMessageDialog(null, 
						"NetWork connection error !", 
						"Add new feed", 
						JOptionPane.ERROR_MESSAGE);
					
				exception.printStackTrace();
				return;
			}finally {
				try {
					if (in != null) {
						in.close();
					}
					if (out != null) {
						out.close();
					}
				} catch (IOException ioe) {
				}
			}
			readTheFilePageContent(localname);
		}
		
		/**
		 * pick up the related content from the web file
		 * @param file
		 * 		the downloaded web file
		 */
		public void readTheFilePageContent(String file) {
		    BufferedReader reader = null;
			String patternPage = "<p";
			String patternScriptStart = "<script";
			String patternScriptEnd = "/script>";
			String patternScript = "<script />";
			String patternTableStart = "<table";
			String patternTableEnd = "/table>";
			String patternUlStart = "<ul";
			String patternUlEnd = "/ul>";
			String patternOlStart = "<ol";
			String patternOlEnd = "/ol>";
			String patternNSptStart = "<noscript";
			String patternNSptEnd = "/noscript>";
			String patternParam = "<param";
			String patternImage = "<img";
			
		    String line = null;
		    StringBuffer strbf = new StringBuffer();
		    
		    try{
		    	reader = new BufferedReader(new FileReader(file));
		        line = reader.readLine();
		        strbf.append("<html>\n");
		        while(line != null) {
		        	if(patternMatch(line, patternScript)) {
		        		line = reader.readLine();
		        		continue;
		        	}// this case ignoring the 'script' lines
		        	else if(patternMatch(line, patternScriptStart)) {
		        		if(!patternMatch(line, patternScriptEnd)){
		        			line = reader.readLine();
		        			while(line != null) {
				        		if(patternMatch(line, patternScriptEnd)){
				        			break;
				        		}
			        			line = reader.readLine();
		        			}
		        		}
		        	}// this case ignoring the 'table' tag lines 
		        	else if(patternMatch(line, patternTableStart)) {
		        		if(!patternMatch(line, patternTableEnd)){
		        			line = reader.readLine();
		        			while(line != null) {
				        		if(patternMatch(line, patternTableEnd)){
				        			break;
				        		}
			        			line = reader.readLine();
		        			}
		        		}
		        	}// this case ignoring the 'ul' tag lines
		        	else if(patternMatch(line, patternUlStart)) {
		        		if(!patternMatch(line, patternUlEnd)){
		        			line = reader.readLine();
		        			while(line != null) {
				        		if(patternMatch(line, patternUlEnd)){
				        			break;
				        		}
			        			line = reader.readLine();
		        			}
		        		}
		        	}// this case ignoring the 'ol' tag lines
		        	else if(patternMatch(line, patternOlStart)) {
		        		if(!patternMatch(line, patternOlEnd)){
		        			line = reader.readLine();
		        			while(line != null) {
				        		if(patternMatch(line, patternOlEnd)){
				        			break;
				        		}
			        			line = reader.readLine();
		        			}
		        		}
		        	}// this case ignoring the 'noscript' tag lines
		        	else if(patternMatch(line, patternNSptStart)){
	        			if(!patternMatch(line, patternNSptEnd)) {
	        				line = reader.readLine();
	        				while(line != null) {
				        		if(patternMatch(line, patternNSptEnd)){
				        			break;
				        		}
			        			line = reader.readLine();
	        				}
	        			}
		        	}// this case ignoring the 'param' tag lines
		        	else if(patternMatch(line, patternParam)){
	        			line = reader.readLine();
		        		continue;
		        	}// this case obtaining the 'p' tag lines without image
		        	else if(patternMatch(line, patternPage)) {
		        		if(!patternMatch(line, patternImage))
		        			strbf.append(line);
			        }// this case obtaining the page content but no tag signed lines
			        else if(isPageNoPageTag(line)){
			        	strbf.append(line);
			        }
		        	line = reader.readLine();
		        }
		    }catch(IOException ioe) {
			    ioe.printStackTrace();
		    }finally {
		    	try {
		    		if(reader != null)
				    	reader.close();
		    	}catch(IOException ioe) {
		    		
		    	}
		    }
		    
		    // delete the temp file
			File temFile = new File(file);
			if(temFile.exists()) {
				temFile.delete();
			}
			// save the content to cache
			saveArticleMap.put(urlPara, strbf.toString());
			
			// show the content on the article field
			if(feedTitleTxt.getText() == null || feedTitleTxt.getText().equals(""))
				htmlLabel.setText("");
			else
				htmlLabel.setText(strbf.toString());
		}
	}
	
	/**
	 * check the read line is page but no page tag
	 * 
	 * @param str
	 * 		the read line from web file
	 * @return
	 * 		true/false
	 */
	public boolean isPageNoPageTag(String str) {
		boolean isPage = false;
		char c;
		for(int i = 0; i < str.length(); i++) {
			c = str.charAt(i);
			if(c == '\t') {
				continue;
			}
			else if(c == ' ') {
				continue;
			}
			
			if(((c >= 'a')&&(c <= 'z'))||((c >= 'A')&&(c <= 'Z'))) {
				isPage = true;
				break;
			}
			else
				break;
		}
		return isPage;
	}
	
	/**
	 * clear the item panel's related fields
	 */
	public void clearLinkPaneElements() {
		feedTitleTxt.setText("");
		feedLinkTxt.setText("");
		feedDateTxt.setText("");
		feedDescTxt.setText("");
		htmlLabel.setText("");
	}
	
	/**
     * Implements the windowClosing method from WindowAdapter/WindowListener to
	 * persist the contents of the data/model.
	 */
	private class ExitListener extends WindowAdapter {

		/**
		 * @see java.awt.event.WindowAdapter#windowClosing(java.awt.event.WindowEvent)
		 */
		public void windowClosing(WindowEvent e) {
			data.persist();
			System.exit(0);
		}
	}
}