de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.rdknn
Class RdKNNTreeHeader

java.lang.Object
  de.lmu.ifi.dbs.elki.persistent.DefaultPageHeader
      de.lmu.ifi.dbs.elki.index.tree.TreeIndexHeader
          de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.rdknn.RdKNNTreeHeader

All Implemented Interfaces:

PageHeader

 class RdKNNTreeHeader
extends TreeIndexHeader

Encapsulates the header information of a RDkNN-Tree. This information is needed for persistent storage.

Author:

Elke Achtert

Field Summary

(package private) int	k_max The maximum number k of reverse kNN queries to be supported.
private static int	SIZE The size of this header in Bytes, which is 4 Bytes (for k_max).

Constructor Summary

RdKNNTreeHeader()
Empty constructor for serialization.

RdKNNTreeHeader(int pageSize, int dirCapacity, int leafCapacity, int dirMinimum, int leafMinimum, int k_max)
Creates a new header with the specified parameters.

Method Summary

void	readHeader(RandomAccessFile file) Initializes this header from the specified file.
int	size() Returns TreeIndexHeader.size() plus the value of SIZE).
void	writeHeader(RandomAccessFile file) Writes this header to the specified file.

Methods inherited from class de.lmu.ifi.dbs.elki.index.tree.TreeIndexHeader

getDirCapacity, getDirMinimum, getLeafCapacity, getLeafMinimum

Methods inherited from class de.lmu.ifi.dbs.elki.persistent.DefaultPageHeader

asByteArray, getPageSize, readHeader

Methods inherited from class java.lang.Object

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

Field Detail

SIZE

private static int SIZE

The size of this header in Bytes, which is 4 Bytes (for k_max).

k_max

int k_max

The maximum number k of reverse kNN queries to be supported.

Constructor Detail

RdKNNTreeHeader

public RdKNNTreeHeader()

Empty constructor for serialization.

RdKNNTreeHeader

public RdKNNTreeHeader(int pageSize,
                       int dirCapacity,
                       int leafCapacity,
                       int dirMinimum,
                       int leafMinimum,
                       int k_max)

Creates a new header with the specified parameters.

Parameters:

pageSize - the size of a page in bytes

dirCapacity - the maximum number of entries in a directory node

leafCapacity - the maximum number of entries in a leaf node

dirMinimum - the minimum number of entries in a directory node

leafMinimum - the minimum number of entries in a leaf node

k_max - the maximum number k of reverse kNN queries to be supported

Method Detail

readHeader

public void readHeader(RandomAccessFile file)
                throws IOException

Initializes this header from the specified file. Calls TreeIndexHeader#readHeader(file) and reads additionally the integer value of k_max from the file.

Specified by:

readHeader in interface PageHeader

Overrides:

readHeader in class TreeIndexHeader

Parameters:

file - the file to which this header belongs

Throws:

IOException - if an I/O-error occurs during reading

writeHeader

public void writeHeader(RandomAccessFile file)
                 throws IOException

Writes this header to the specified file. Calls TreeIndexHeader.writeHeader(java.io.RandomAccessFile) and writes additionally the integer value of k_max to the file.

Specified by:

writeHeader in interface PageHeader

Overrides:

writeHeader in class TreeIndexHeader

Parameters:

file - the file to which this header belongs

Throws:

IOException - IOException if an I/O-error occurs during writing

size

public int size()

Returns TreeIndexHeader.size() plus the value of SIZE).

Specified by:

size in interface PageHeader

Overrides:

size in class TreeIndexHeader

Returns:

the size of this header in Bytes