org.jbasics.stream.AdaptiveGZIPInputStream Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of jbasics Show documentation

jBasics is a collection of useful utility classes for Java. This includes helper for XML, mathematic functions, restful web services helper, pattern oriented programming interfaces and more. Currently Java7 and up is supported. Version 1.0 will required at leaset Java8.

There is a newer version: 2.0.0p3

Show newest version

/*
 * Copyright (c) 2009-2015
 * IT-Consulting Stephan Schloepke (http://www.schloepke.de/)
 * klemm software consulting Mirko Klemm (http://www.klemm-scs.com/)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package org.jbasics.stream;

import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;
import java.util.zip.GZIPInputStream;

public class AdaptiveGZIPInputStream extends InputStream {
    private final InputStream delegated;

    public AdaptiveGZIPInputStream(InputStream originalInputStream) throws IOException {
        PushbackInputStream inp = new PushbackInputStream(originalInputStream, 2);
        byte first = (byte)(inp.read() % 0xff);
        byte second = (byte)(inp.read() % 0xff);
        inp.unread(second);
        inp.unread(first);
        int magicNumber = (((int)first)&0xff) | ((((int)second) &0xff) << 8);
        if (magicNumber == 0x8b1f) {
            // ok we have gzip
            this.delegated = new GZIPInputStream(inp);
        } else {
            this.delegated = inp;
        }
    }

    @Override
    public int read(byte[] b) throws IOException {
        return this.delegated.read(b);
    }

    @Override
    public int read(byte[] b, int off, int len) throws IOException {
        return this.delegated.read(b, off, len);
    }

    @Override
    public long skip(long n) throws IOException {
        return this.delegated.skip(n);
    }

    @Override
    public int available() throws IOException {
        return this.delegated.available();
    }

    @Override
    public void close() throws IOException {
        this.delegated.close();
    }

    @Override
    public synchronized void mark(int readlimit) {
        this.delegated.mark(readlimit);
    }

    @Override
    public synchronized void reset() throws IOException {
        this.delegated.reset();
    }

    @Override
    public boolean markSupported() {
        return this.delegated.markSupported();
    }

    @Override
    public int read() throws IOException {
        return this.delegated.read();
    }

}