import java.util.zip.GZIPInputStream;
import java.io.OutputStream;
import java.io.FileOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class JavaUncompress{
	public static void main(String args[]){
		try{
			//To Uncompress GZip File Contents we need to open the gzip file.....
			if(args.length<=0){
				System.out.println("Please enter the valid file name");
			}
			else{
				String inFilename = args[0];
				System.out.println("Opening the gzip file.......................... :  opened");
				GZIPInputStream gzipInputStream = null;
				FileInputStream fileInputStream = null;
				gzipInputStream = new GZIPInputStream(new FileInputStream(inFilename));
				System.out.println("Opening the output file............. : opened");
				String outFilename = inFilename +".pdf";
				OutputStream out = new FileOutputStream(outFilename);
				System.out.println("Trsansferring bytes from the compressed file to the output file........:  Transfer successful");
				byte[] buf = new byte[1024];  //size can be changed according to programmer's need.
				int len;
				while ((len = gzipInputStream.read(buf)) > 0) {
					out.write(buf, 0, len);
				}
				System.out.println("The file and stream is ......closing.......... : closed"); 
				gzipInputStream.close();
				out.close();
			}
		}
		catch(IOException e){
			System.out.println("Exception has been thrown" + e);
		}
	}
}