com.metamatrix.core.util
Class ChecksumUtil

java.lang.Object
  com.metamatrix.core.util.ChecksumUtil

public class ChecksumUtil
extends java.lang.Object

This utility class provides mechanisms for computing the checksum.

Field Summary

protected static int

BUFFER_SIZE

Constructor Summary

ChecksumUtil()

Method Summary

static java.util.zip.Checksum	computeChecksum(java.io.InputStream stream) Compute and return the checksum (using the default CRC-32 algorithm) of the contents on the specified stream.
static long	computeChecksum(java.io.InputStream stream, java.util.zip.Checksum algorithm) Compute the checksum of the contents on the specified stream using the supplied Checksum algorithm, and modify that Checksum instance with the checksum value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BUFFER_SIZE

protected static final int BUFFER_SIZE

See Also:

Constant Field Values

Constructor Detail

ChecksumUtil

public ChecksumUtil()

Method Detail

computeChecksum

public static java.util.zip.Checksum computeChecksum(java.io.InputStream stream)
                                              throws java.io.IOException

Compute and return the checksum (using the default CRC-32 algorithm) of the contents on the specified stream. This method closes the stream upon completion.

Parameters:

stream - the stream containing the contents for which the checksum is to be computed; may not be null

Returns:

the Checksum for the contents

Throws:

java.lang.AssertionError - if stream is null

java.io.IOException - if there is an error reading the stream

computeChecksum

public static long computeChecksum(java.io.InputStream stream,
                                   java.util.zip.Checksum algorithm)
                            throws java.io.IOException

Compute the checksum of the contents on the specified stream using the supplied Checksum algorithm, and modify that Checksum instance with the checksum value. This method closes the stream upon completion.

Parameters:

stream - the stream containing the contents for which the checksum is to be computed; may not be null

algorithm - the checksum algorithm to be used.

Returns:

the number of bytes from stream that were processed

Throws:

java.lang.AssertionError - if stream or algorithm is null

java.io.IOException - if there is an error reading the stream