Package gov.nih.mipav.model.file

Class MetadataExtractor.ByteArrayReader

java.lang.Object

gov.nih.mipav.model.file.MetadataExtractor.RandomAccessReader

gov.nih.mipav.model.file.MetadataExtractor.ByteArrayReader

Enclosing class:

MetadataExtractor

public class MetadataExtractor.ByteArrayReader
extends MetadataExtractor.RandomAccessReader

Provides methods to read specific values from a byte array, with a consistent, checked exception structure for issues.

By default, the reader operates with Motorola byte order (big endianness). This can be changed by calling setMotorolaByteOrder(boolean).

Author:

Drew Noakes https://drewnoakes.com

Field Summary

Fields

Modifier and Type	Field	Description
private final int	_baseOffset
private final byte[]	_buffer

Constructor Summary

Constructors

Constructor	Description
ByteArrayReader(byte[] buffer)
ByteArrayReader(byte[] buffer, int baseOffset)

Method Summary

Modifier and Type	Method	Description
byte	getByte(int index)	Gets the byte value at the specified byte index.
byte[]	getBytes(int index, int count)	Returns the required number of bytes from the specified index from the underlying source.
long	getLength()	Returns the length of the data source in bytes.
protected boolean	isValidIndex(int index, int bytesRequested)
int	toUnshiftedOffset(int localOffset)
protected void	validateIndex(int index, int bytesRequested)	Ensures that the buffered bytes extend to cover the specified index.

Methods inherited from class gov.nih.mipav.model.file.MetadataExtractor.RandomAccessReader

getBit, getDouble64, getFloat32, getInt16, getInt24, getInt32, getInt64, getInt8, getNullTerminatedBytes, getNullTerminatedString, getNullTerminatedStringValue, getS15Fixed16, getString, getString, getStringValue, getUInt16, getUInt32, getUInt8, isMotorolaByteOrder, setMotorolaByteOrder

Methods inherited from class java.lang.Object

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

Field Details

_buffer

private final byte[] _buffer

_baseOffset

private final int _baseOffset

Constructor Details

ByteArrayReader

public ByteArrayReader(byte[] buffer)

ByteArrayReader

public ByteArrayReader(byte[] buffer,
 int baseOffset)

Method Details

toUnshiftedOffset

public int toUnshiftedOffset(int localOffset)

Specified by:

toUnshiftedOffset in class MetadataExtractor.RandomAccessReader

getLength

public long getLength()

Description copied from class: MetadataExtractor.RandomAccessReader

Returns the length of the data source in bytes.

This is a simple operation for implementations (such as MetadataExtractor.RandomAccessFileReader and MetadataExtractor.ByteArrayReader) that have the entire data source available.

Users of this method must be aware that sequentially accessed implementations such as MetadataExtractor.RandomAccessStreamReader will have to read and buffer the entire data source in order to determine the length.

Specified by:

getLength in class MetadataExtractor.RandomAccessReader

Returns:

the length of the data source, in bytes.

getByte

public byte getByte(int index)
             throws IOException

Description copied from class: MetadataExtractor.RandomAccessReader

Gets the byte value at the specified byte index.

Implementations should not perform any bounds checking in this method. That should be performed in validateIndex and isValidIndex.

Specified by:

getByte in class MetadataExtractor.RandomAccessReader

Parameters:

index - The index from which to read the byte

Returns:

The read byte value

Throws:

IOException - if the byte is unable to be read

validateIndex

protected void validateIndex(int index,
 int bytesRequested)
                      throws IOException

Description copied from class: MetadataExtractor.RandomAccessReader

Ensures that the buffered bytes extend to cover the specified index. If not, an attempt is made to read to that point.

If the stream ends before the point is reached, a MetadataExtractor.BufferBoundsException is raised.

Specified by:

validateIndex in class MetadataExtractor.RandomAccessReader

Parameters:

index - the index from which the required bytes start

bytesRequested - the number of bytes which are required

Throws:

IOException - if the stream ends before the required number of bytes are acquired

isValidIndex

protected boolean isValidIndex(int index,
 int bytesRequested)
                        throws IOException

Specified by:

isValidIndex in class MetadataExtractor.RandomAccessReader

Throws:

IOException

getBytes

public byte[] getBytes(int index,
 int count)
                throws IOException

Description copied from class: MetadataExtractor.RandomAccessReader

Returns the required number of bytes from the specified index from the underlying source.

Specified by:

getBytes in class MetadataExtractor.RandomAccessReader

Parameters:

index - The index from which the bytes begins in the underlying source

count - The number of bytes to be returned

Returns:

The requested bytes

Throws:

IOException - if the byte is unable to be read