Check sum for an InputStream : Zip Tar File « File Input Output « Java






Check sum for an InputStream

       
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.zip.Adler32;
import java.util.zip.CheckedInputStream;




/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


/**
 * implements checksum related utilities
 *
 * @author <a href="mailto:taylor@apache.org">David Sean Taylor </a>
 * @version $Id: ChecksumHelper.java 516448 2007-03-09 16:25:47Z ate $
 */
final class ChecksumHelper
{
    public static long getChecksum(InputStream is)
    {
        CheckedInputStream cis = null;        
        long checksum = 0;
        try 
        {
            cis = new CheckedInputStream(is, new Adler32());
            byte[] tempBuf = new byte[128];
            while (cis.read(tempBuf) >= 0) 
            {
            }
            checksum = cis.getChecksum().getValue();
        } 
        catch (IOException e) 
        {
            checksum = 0;
        }
        finally
        {
            if (cis != null)
            {
                try
                {
                    cis.close();
                }
                catch (IOException ioe)
                {                    
                }
            }
        }
        return checksum;
    }
}
        

   
    
    
    
    
    
    
  








Related examples in the same category

1.Extract contents of a zip file
2.List the contents of a zip file
3.Read entries in a zip / compressed file
4.Decompress a zip file using ZipInputStream
5.Decompress a zip file using ZipFile
6.Create checksum for a zip file
7.Read a zip file checksum value
8.Create a zip file with java.util.zip package
9.Extract file/files from a zip file
10.Read files within a zip file
11.Retrieve a compressed file from a ZIP file
12.Retrieve the contents of a ZIP file
13.Making a zip file of directory including its subdirectories recursively
14.Displaying contents of a compressed zip file
15.Compress a Byte Array
16.Decompress a Byte Array
17.Read zip file
18.Write Zip file
19.The java.util.zip package can be used to create a checksum.
20.Read the content of a zip file ZipFile
21.List the entries of a zip file
22.Compressing Streams: Zipper, Java example
23.Compressing Streams: Parity Checksum
24.Compressing Streams: File Summer
25.Create a simple ZIP File: not retain any directory path information about the files.
26.Decompress a ZIP file.
27.Decompressing a Byte Array
28.Zip unzip byte array
29.Creating a ZIP File
30.Listing the Contents of a ZIP File
31.Retrieving a Compressed File from a ZIP File
32.Calculating the Checksum of a Byte Array (Compute Adler-32 checksum)
33.Compute CRC-32 checksum
34.Calculating the Checksum of a File
35.Compress string(byte array) by Deflater
36.Use Java code to zip a folder
37.Uses Zip compression to compress any number of files given on the command line
38.Load zip file and scan zip file
39.Reading the Contents of a ZIP File
40.UnZip -- print or unzip a JAR or PKZIP file using java.util.zip
41.Tape Archive Lister: Tar file
42.Compressing a Byte Array
43.Tar file stream
44.Tar file and untar file
45.bzip source code
46.Unpack an archive from a URL
47.Compare two zip files
48.Determine whether a file is a ZIP File.
49.Zip up a directory
50.Check sum for a path
51.Extract zip file to destination folder
52.Return the first directory of this archive. This is needed to determine the plugin directory
53.Makes a zip file named xmlFileName from xmlURL at path
54.Unzipps a zip file placed at zipURL to path
55.A single checksum calculation for multiple files
56.Put file To Zip File
57.Provides both writing and reading from a file which is transparently compressed in Zip
58.TarInputStream reads a UNIX tar archive as an InputStream
59.TarOutputStream writes a UNIX tar archive as an OutputStream
60.Package files utility
61.Zip Compare
62.Unpack a segment from a zip
63.Unpack a zip file
64.Unzip file to a directory
65.Zip a list of file into one zip file.
66.Validate that an archive contains a named entry
67.A frame with a text area to show the contents of a file inside a ZIP archive
68.Compress object and decompress
69.Util for extracting *.jar, *.war and *.zip archives.