import java.io.*;
import java.util.zip.*;

public class CompressingFile {
	public static void doCompressFile(String inFileName){
		try{
			File file = new File(inFileName);
			System.out.println(" you are going to gzip the  : " + file + "file");
			FileOutputStream fos = new FileOutputStream(file + ".gz");
			System.out.println(" Now the name of this gzip file is  : " + file + ".gz" );
			GZIPOutputStream gzos = new GZIPOutputStream(fos);
			System.out.println(" opening the input stream");
			FileInputStream fin = new FileInputStream(file);
			BufferedInputStream in = new BufferedInputStream(fin);
			System.out.println("Transferring file from" + inFileName + " to " + file + ".gz");
			byte[] buffer = new byte[1024];
			int i;
			while ((i = in.read(buffer)) >= 0){
				gzos.write(buffer,0,i);
			}
			System.out.println(" file is in now gzip format");
			in.close();
			gzos.close();
		}
		catch(IOException e){
			System.out.println("Exception is" + e);
		}
	}		
	public static void main(String args[]){
		if(args.length!=1){
			System.err.println("Please enter the file name which needs to be compressed ");
		}
		else{
			doCompressFile(args[0]);
		}
	}
}