Java Programming

Hey folks,

i'm really having a hard time with a - propably - easy to solve problem.

I want too:

-> compress a string using gzip
-> decompress the string

I've written a simple main-class to test this, but unfortunately the resulting output string doesnt equal the input string which is the good old "foo"....

Here is my simple main:

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class TestGzip {

	public static void main(String[] args) throws UnsupportedEncodingException{
	
		byte[] baFileContent = new String("foo").getBytes();	
		
		// print out
		System.out.println("original string as int: ");
		String output = "";
		for(int i = 0; i < baFileContent.length; i++) {
			output += baFileContent[i] + " ";
		}
		System.out.println(output);
		
		/*
		 * compression
		 */
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		GZIPOutputStream zos;
		try {
			zos = new GZIPOutputStream(baos);
			for(int i = 0; i < baFileContent.length; i++) {
			    zos.write(baFileContent);

			}

		zos.close();

			baos.close();

		} catch (IOException e) {

			System.out.println(e.getMessage());

		}

		byte[] baFileContentCompressed = baos.toByteArray();

		// print out

		System.out.println("string compressed as int: ");

		output = "";

		for(int i = 0; i < baFileContentCompressed.length; i++) {

			output += baFileContentCompressed[i] + " ";

		}

		System.out.println(output);



		/*

		* decompression

		*/

		ByteArrayInputStream bais = new ByteArrayInputStream(baFileContentCompressed);

		GZIPInputStream zis = null;

		byte[] buffer = new byte[ 8192 ];

		// the result

		byte[] baFileContentDecompressed = null;

		

		baos = new ByteArrayOutputStream();

		try {

			zis = new GZIPInputStream(bais);

			for(int len; (len = zis.read(buffer)) != -1; ) {

				baos.write(len);

			}	

			zis.close();

			bais.close();

			baos.close();

			baFileContentDecompressed = baos.toByteArray();

		} catch (IOException e) {

			System.out.println(e.getMessage());

		}

		//print out

		System.out.println("string decompressed as int: ");

		output = "";

		for(int i = 0; i < baFileContentDecompressed.length; i++) {

			output += baFileContentDecompressed[i] + " ";

		}

		System.out.println(output);

	}

}





The output is:


original string as int: 
102 111 111 
string compressed as int: 
31 -117 8 0 0 0 0 0 0 0 75 -53 -49 7 0 33 101 115 -116 3 0 0 0 
string decompressed as int: 
3 
As you can see:



- input is "102 111 111" 

- but the output is "3"



I'm pretty sure the error lies in the decompression code segment:


		/*
		 * decompression
		 */
		ByteArrayInputStream bais = new ByteArrayInputStream(baFileContentCompressed);
		GZIPInputStream zis = null;
		byte[] buffer = new byte[ 8192 ];
		// the result
		byte[] baFileContentDecompressedDecoded = null;
		
		baos = new ByteArrayOutputStream();
		try {
			zis = new GZIPInputStream(bais);
			for(int len; (len = zis.read(buffer)) != -1; ) {
				baos.write(len);
			}	
			zis.close();
			bais.close();
			baos.close();
			baFileContentDecompressedDecoded = baos.toByteArray();
		} catch (IOException e) {
			System.out.println(e.getMessage());
		}
but i just don't see any errors.....



Any help will be greatly appreciated!