是GZip Stream

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 * Aduna licenses this file to you under the terms of the Aduna BSD 

 * License (the "License"); you may not use this file except in compliance 

 * with the License. See the LICENSE.txt file distributed with this work 

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 * Unless required by applicable law or agreed to in writing, software 

 * distributed under the License is distributed on an "AS IS" BASIS, 

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 * implied. See the License for the specific language governing permissions

 * and limitations under the License.

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import java.io.IOException;

import java.io.InputStream;

import java.util.Arrays;
/*来自 
 NowJava.com - 时代Java*/


public class Main{

    /**

     * GZIP header magic number bytes, like found in a gzipped files, which are

     * encoded in Intel format (i.e. little indian).

     */

    private final static byte MAGIC_NUMBER[] = { (byte) 0x1f, (byte) 0x8b };

    public static boolean isGZipStream(InputStream in)