Zlib compression Using Deflate and Inflate classes in Java

Question

I want trying to use the Deflate and Inflate classes in java.util.zip for zlib compression.

I am able to compress the code using Deflate, but while decompressing, I

Answer 1

Paŭlo Ebermann's code can be further improved by using try-with-resources:

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

public class ZLibCompression
{
    public static void compress(File raw, File compressed) throws IOException
    {
        try (InputStream inputStream = new FileInputStream(raw);
             OutputStream outputStream = new DeflaterOutputStream(new FileOutputStream(compressed)))
        {
            copy(inputStream, outputStream);
        }
    }

    public static void decompress(File compressed, File raw)
            throws IOException
    {
        try (InputStream inputStream = new InflaterInputStream(new FileInputStream(compressed));
             OutputStream outputStream = new FileOutputStream(raw))
        {
            copy(inputStream, outputStream);
        }
    }

    public static String decompress(File compressed) throws IOException
    {
        try (InputStream inputStream = new InflaterInputStream(new FileInputStream(compressed)))
        {
            return toString(inputStream);
        }
    }

    private static String toString(InputStream inputStream)
    {
        try (Scanner scanner = new Scanner(inputStream).useDelimiter("\\A"))
        {
            return scanner.hasNext() ? scanner.next() : "";
        }
    }

    private static void copy(InputStream inputStream, OutputStream outputStream)
            throws IOException
    {
        byte[] buffer = new byte[1000];
        int length;

        while ((length = inputStream.read(buffer)) > 0)
        {
            outputStream.write(buffer, 0, length);
        }
    }
}