org.basex.index

Class Names

java.lang.Object

org.basex.util.hash.TokenSet

org.basex.index.Names

All Implemented Interfaces:

java.lang.Iterable<byte[]>, Index

public final class Names
extends TokenSet
implements Index

This class indexes and organizes the tags or attribute names, used in an XML document.

Author:

BaseX Team 2005-12, BSD License, Christian Gruen, Lukas Kircher

Field Summary

Fields

Modifier and Type	Field and Description
protected Stats[]	stats Statistical information.

Fields inherited from class org.basex.util.hash.TokenSet

CAP, keys, size

Constructor Summary

Constructors

Constructor and Description
Names(DataInput in, MetaData md) Constructor, specifying an input file.
Names(MetaData md) Default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Closes the index.
int	count(IndexToken token) Returns the (approximate/estimated) number of hits for the specified token.
EntryIterator	entries(byte[] prefix) Returns all entries that start with the specified prefix.
int	index(byte[] n, byte[] v, boolean st) Indexes a name and returns its unique id.
void	index(int n, byte[] v) Adds a value to the statistics of the specified key.
byte[]	info() Returns information on the index structure.
void	init() Initializes the statistics.
IndexIterator	iter(IndexToken token) Returns an iterator for the index results.
protected void	rehash() Resizes the hash table.
Stats	stat(int id) Returns the statistics for the specified key id.
void	write(DataOutput out) Writes the token set to the specified output.

Methods inherited from class org.basex.util.hash.TokenSet

add, delete, id, iterator, key, keys, read, size, toString

Methods inherited from class java.lang.Object

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

Field Detail

stats

protected Stats[] stats

Statistical information.

Constructor Detail

Names

public Names(MetaData md)

Default constructor.

Parameters:

md - meta data

Names

public Names(DataInput in,
     MetaData md)
      throws java.io.IOException

Constructor, specifying an input file.

Parameters:

in - input stream

md - meta data

Throws:

java.io.IOException - I/O exception

Method Detail

init

public void init()

Initializes the statistics.

index

public int index(byte[] n,
        byte[] v,
        boolean st)

Indexes a name and returns its unique id.

Parameters:

n - name to be added

v - value, added to statistics

st - statistics flag

Returns:

name id

index

public void index(int n,
         byte[] v)

Adds a value to the statistics of the specified key. Evaluates the value for the specified key id.

Parameters:

n - name id

v - value, added to statistics

write

public void write(DataOutput out)
           throws java.io.IOException

Description copied from class: TokenSet

Writes the token set to the specified output.

Overrides:

write in class TokenSet

Parameters:

out - output stream

Throws:

java.io.IOException - I/O exception

stat

public Stats stat(int id)

Returns the statistics for the specified key id.

Parameters:

id - id

Returns:

statistics

info

public byte[] info()

Description copied from interface: Index

Returns information on the index structure.

Specified by:

info in interface Index

Returns:

info

entries

public EntryIterator entries(byte[] prefix)

Description copied from interface: Index

Returns all entries that start with the specified prefix.

Specified by:

entries in interface Index

Parameters:

prefix - prefix

Returns:

entries

rehash

protected void rehash()

Description copied from class: TokenSet

Resizes the hash table.

Overrides:

rehash in class TokenSet

close

public void close()

Description copied from interface: Index

Closes the index.

Specified by:

close in interface Index

iter

public IndexIterator iter(IndexToken token)

Description copied from interface: Index

Returns an iterator for the index results.

Specified by:

iter in interface Index

Parameters:

token - token to be found

Returns:

sorted pre values for the token

count

public int count(IndexToken token)

Description copied from interface: Index

Returns the (approximate/estimated) number of hits for the specified token.

Specified by:

count in interface Index

Parameters:

token - token to be found

Returns:

number of hits