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

class InFile 
{
  private boolean mIsOkay;
	private URL mInFile;
	private URLConnection mConnection;
	private DataInputStream mInData;
	private String mStrLine;

  public InFile()
	{
	  mIsOkay=false;
	}
	public InFile(URL resBase,String strHostPathFileName)throws Exception
	{
	  mIsOkay=false;
	  open(resBase,strHostPathFileName);
	}
	public InFile(String strHostPathFileName)throws Exception
	{
	  mIsOkay=false;
		open(strHostPathFileName);
	}
	public InFile(String resBase,String strHostPathFileName)throws Exception
	{
	  mIsOkay=false;
		open(resBase,strHostPathFileName);
	}
	public void open(URL resBase,String strHostPathFileName)throws Exception
	{
	  close();
		try{mInFile=new URL(resBase,strHostPathFileName);}
		catch(MalformedURLException exception){throw new Exception();}
		try{mConnection=mInFile.openConnection();}
		catch(Exception exception){throw new Exception();}
		try{mInData=new DataInputStream(mConnection.getInputStream());}
		catch(Exception exception){throw new Exception();}
		mIsOkay=true;
	}
	public void open(String resBase,String strHostPathFileName)throws Exception
	{
	  open(resBase+strHostPathFileName);
	}
	public void open(String strHostPathFileName)throws Exception
	{
	  close();
		try{mInFile=new URL(strHostPathFileName);}
		catch(MalformedURLException exception){throw new Exception();}
		try{mConnection=mInFile.openConnection();}
		catch(IOException ioException){throw new Exception();}
		try{mInData=new DataInputStream(mConnection.getInputStream());}
		catch(Exception exception){throw new Exception();}
		mIsOkay=true;
	}
	public void close()
	{
	  if(!isOkay())return;
		try{mInData.close();}
		catch(Exception exception){;}
		mIsOkay=false;
	}
	public String readLine()throws Exception
	{
	  if(!isOkay())throw new Exception();
		try{mStrLine=new String(mInData.readLine());}
		catch(IOException ioException){throw new Exception();}
		return mStrLine;
	}
	public boolean isOkay()
	{
	  return mIsOkay;
	}
};