org.geotools.data.shapefile.shp
Class IndexFile

java.lang.Object
  org.geotools.data.shapefile.shp.IndexFile

public class IndexFile

extends java.lang.Object

IndexFile parser for .shx files.
For now, the creation of index files is done in the ShapefileWriter. But this can be used to access the index.
For details on the index file, see
"ESRI(r) Shapefile - A Technical Description"
* 'An ESRI White Paper . May 1997'

Author:

Ian Schneider

Constructor Summary

IndexFile(java.nio.channels.ReadableByteChannel channel)
Load the index file from the given channel.

IndexFile(java.nio.channels.ReadableByteChannel channel, boolean useMemoryMappedBuffer)
Load the index file from the given channel.

Method Summary

void	close()
protected void	finalize()
int	getContentLength(int index) Get the content length of the given record in bytes, not 16 bit words.
ShapefileHeader	getHeader() Get the header of this index file.
int	getOffset(int index) Get the offset of the record (in 16-bit words).
int	getOffsetInBytes(int index) Get the offset of the record (in real bytes, not 16-bit words).
int	getRecordCount() Get the number of records in this index.

Methods inherited from class java.lang.Object

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

Constructor Detail

IndexFile

public IndexFile(java.nio.channels.ReadableByteChannel channel)
          throws java.io.IOException

Load the index file from the given channel.

Parameters:

channel - The channel to read from.

Throws:

java.io.IOException - If an error occurs.

IndexFile

public IndexFile(java.nio.channels.ReadableByteChannel channel,
                 boolean useMemoryMappedBuffer)
          throws java.io.IOException

Load the index file from the given channel.

Parameters:

channel - The channel to read from.

Throws:

java.io.IOException - If an error occurs.

Method Detail

getHeader

public ShapefileHeader getHeader()

Get the header of this index file.

Returns:

The header of the index file.

close

public void close()
           throws java.io.IOException

Throws:

java.io.IOException

finalize

protected void finalize()
                 throws java.lang.Throwable

Throws:

java.lang.Throwable

See Also:

Object.finalize()

getRecordCount

public int getRecordCount()

Get the number of records in this index.

Returns:

The number of records.

getOffset

public int getOffset(int index)
              throws java.io.IOException

Get the offset of the record (in 16-bit words).

Parameters:

index - The index, from 0 to getRecordCount - 1

Returns:

The offset in 16-bit words.

Throws:

java.io.IOException

getOffsetInBytes

public int getOffsetInBytes(int index)
                     throws java.io.IOException

Get the offset of the record (in real bytes, not 16-bit words).

Parameters:

index - The index, from 0 to getRecordCount - 1

Returns:

The offset in bytes.

Throws:

java.io.IOException

getContentLength

public int getContentLength(int index)
                     throws java.io.IOException

Get the content length of the given record in bytes, not 16 bit words.

Parameters:

index - The index, from 0 to getRecordCount - 1

Returns:

The lengh in bytes of the record.

Throws:

java.io.IOException