Free "tail -f" Tool for all Platforms: Tail for Windows, Tail for Linux and Tail for Mac

/******************************************************************************
 
Copyright (C) 2006  MakeLogic

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA


Date		: 14th April 2006
Authors		: MakeLogic

Design		: Ujjwal
Developer	: Dharma

********************************************************************************/


package com.makeLogic;

import java.awt.event.ActionEvent;

import javax.swing.AbstractAction;
import javax.swing.JDialog;

import java.awt.*;
import java.net.*;
import java.io.*;

import com.makeLogic.utils.HelpDialog;
import com.makeLogic.utils.Trace;

public class HelpDocumentAction extends AbstractAction{

	TailMDI tailMDI;
	final String helpURL = "http://www.makelogic.com/tail/TailHelp.htm";
	final String localHelpFileName = Tail.INSTALL_DIR + "TailHelp.htm";
	final String helpFileInJar = "TailHelpInJar.htm";

	public HelpDocumentAction(TailMDI tailMDI){
		super("Help");

		Trace.enter("HelpDocumentAction.HelpDocumentAction");
		
		this.tailMDI = tailMDI;

		Trace.exit("HelpDocumentAction.HelpDocumentAction");
	}

	public void actionPerformed(ActionEvent ae){

		Trace.enter("HelpDocumentAction.actionPerformed");

		/*
		HelpDialog helpDialog = new HelpDialog(Tail.tailMDI);
		helpDialog.show();
		*/

		//..1. Open the help documentation from the internet
		//..2. If help document is found on the internet, copy the file and overwrite the local file
		//..3. If internet is not accessible, open the local file
		//..4. If the local file is not found, open the jar file resource and make a local copy

		//..Check if internet accessible
		try
		{
			//..Debug
			//..System.out.println("..ML.. Getting help from internet");


			//..Embed uid in the URL
			URL url = new URL(helpURL+"?uid="+CheckForNewUpdates.uid);
			Object obj = url.getContent();
			//..System.out.println("..ML.. Content : "+obj);

			//..Internet accessible
			HyperActive.openURL(helpURL+"?uid="+CheckForNewUpdates.uid);

			//..Save the document
			FileOutputStream fos = new FileOutputStream(localHelpFileName);
			InputStream is = url.openStream();

			byte[] data = new byte[1024];
			int bytesRead = 0;
			while((bytesRead = is.read(data))!=-1)
			{
				fos.write(data,0,bytesRead);
			}

			fos.flush();
			fos.close();

			//..Debug
			//System.out.println("..ML.. New help file written");

			return;
		}
		catch(IOException ioe)
		{
			//..No Trace.exception call here

			//..Debug
			//..System.out.println("..ML.. No internet connection");
			//..Could not connect to internet
			//..Open the local file
			//..Get current classloader 

			//..Try to open the local help file
			File helpFile = new File(localHelpFileName);
			//..Check if file exists
			if(helpFile.exists())
			{

				HyperActive.openURL(localHelpFileName);

				//..Debug
				//..System.out.println("..ML.. Opened the local help file");

				return;
			}
			else
			{
				//..Debug
				//..System.out.println("..ML.. Local help file not found");

				//..Open the help file from the jar file
				ClassLoader cl = this.getClass().getClassLoader();
				Toolkit toolkit = Toolkit.getDefaultToolkit();
				String html = getHTML(cl.getResourceAsStream(helpFileInJar));

				//..Debug
				//..System.out.println("..ML.. HELP\n\n"+html+"\n\n");

				try
				{
					FileWriter fw = new FileWriter(localHelpFileName);
					fw.write(html);
					fw.flush();
					fw.close();
				}
				catch(Exception excp)
				{
					Trace.exception(excp);
					//..Debug
					//..System.out.println("..ML.. Could not create a local help file from the jar file");
				}

				//..Debug
				//..System.out.println("..ML.. Created a local help file from the jar file");

				HyperActive.openURL(localHelpFileName);

				//..Debug
				//..System.out.println("..ML.. Opened the help file created from the jar file");
			}
		}

		Trace.exit("HelpDocumentAction.actionPerformed");
	}


	//..getHTML
	public String getHTML(InputStream htmlStream)
	{
		String returnHtml = "";
		String line = "";

		try
		{
			DataInputStream dis = new DataInputStream(htmlStream);

			while(true)
			{
				line = dis.readLine();

				if(line != null)
				{
					returnHtml += line;
				}
				else
				{
					break;
				}
			}

			return returnHtml;
		}
		catch(Exception ex)
		{
			//..No Trace.exception call here
			return "";
		}
	}
}