org.mycore.datamodel.ifs
Class MCRContentInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          org.mycore.datamodel.ifs.MCRContentInputStream

All Implemented Interfaces:

Closeable

public class MCRContentInputStream
extends FilterInputStream

This input stream is used by the MyCoRe filesystem classes to read the content of a file and import it into the System. MCRContentInputStream provides the header of the file that is read (the first 64k) for content type detection purposes, counts the number of bytes read and builds an MD5 checksum String while content goes through this input stream.

Version:

$Revision: 13085 $ $Date: 2008-02-06 18:27:24 +0100 (Mi, 06 Feb 2008) $

Author:

Frank Lützenkirchen

Field Summary

protected MessageDigest	digest The MD5 checksum of all bytes read through this stream
protected byte[]	header The header of the file read
protected static int	headerSize The number of bytes that will be read for content type detection
protected long	length The total number of bytes read so far

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

MCRContentInputStream(InputStream in)
Constructs a new MCRContentInputStream

Method Summary

static MessageDigest	buildMD5Digest() Builds a MessageDigest instance for MD5 checksum computation.
byte[]	getHeader() Returns the first 64 k of the underlying input stream.
long	getLength() Returns the number of bytes read so far
byte[]	getMD5() Returns the MD5 message digest that has been built during reading of the underlying input stream.
String	getMD5String() Returns the MD5 checksum as a String
static String	getMD5String(MessageDigest digest) Given an MD5 message digest, returns the MD5 checksum as a String
int	read()
int	read(byte[] buf, int off, int len)

Methods inherited from class java.io.FilterInputStream

available, close, mark, markSupported, read, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

headerSize

protected static final int headerSize

The number of bytes that will be read for content type detection

See Also:

Constant Field Values

digest

protected MessageDigest digest

The MD5 checksum of all bytes read through this stream

length

protected long length

The total number of bytes read so far

header

protected byte[] header

The header of the file read

Constructor Detail

MCRContentInputStream

public MCRContentInputStream(InputStream in)
                      throws MCRException

Constructs a new MCRContentInputStream

Parameters:

in - the InputStream to read from

Throws:

MCRConfigurationException - if java classes supporting MD5 checksums are not found

MCRException

Method Detail

read

public int read()
         throws IOException

Overrides:

read in class FilterInputStream

Throws:

IOException

read

public int read(byte[] buf,
                int off,
                int len)
         throws IOException

Overrides:

read in class FilterInputStream

Throws:

IOException

getHeader

public byte[] getHeader()

Returns the first 64 k of the underlying input stream. This is used for content type detection during file import into MyCoRe.

Returns:

the first 64 k of the input stream

getLength

public long getLength()

Returns the number of bytes read so far

Returns:

the number of bytes read

getMD5

public byte[] getMD5()

Returns the MD5 message digest that has been built during reading of the underlying input stream.

Returns:

the MD5 message digest checksum of all bytes that have been read

getMD5String

public String getMD5String()

Returns the MD5 checksum as a String

Returns:

the MD5 checksum as a String of hex digits

getMD5String

public static String getMD5String(MessageDigest digest)

Given an MD5 message digest, returns the MD5 checksum as a String

Returns:

the MD5 checksum as a String of hex digits

buildMD5Digest

public static MessageDigest buildMD5Digest()

Builds a MessageDigest instance for MD5 checksum computation.

Throws:

MCRConfigurationException - if no java classes that support MD5 algorithm could be found