org.basex.util
Class TokenSet

java.lang.Object
  extended by org.basex.util.TokenSet
Direct Known Subclasses:
FNIndex, IntMap, MemValues, Names, ObjectMap, StopWords, TokenMap

public class TokenSet
extends Object

This is a simple hash set, storing keys in byte arrays. The TokenMap class extends it to a hash map.

Author:
Workgroup DBIS, University of Konstanz 2005-10, ISC License, Christian Gruen

Constructor Summary
TokenSet()
          Constructor.
TokenSet(DataInput in)
          Constructor.
 
Method Summary
 int add(byte[] key)
          Indexes the specified key and returns the offset of the added key.
 int delete(byte[] key)
          Deletes the specified key.
 int id(byte[] key)
          Returns the id of the specified key or 0 if key was not found.
 byte[] key(int i)
          Returns the specified key.
 byte[][] keys()
          Returns the hash keys.
 void read(DataInput in)
          Reads the token set from the specified input.
 int size()
          Returns number of entries.
 void write(DataOutput out)
          Writes the token set to the specified output.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

TokenSet

public TokenSet()
Constructor.


TokenSet

public TokenSet(DataInput in)
         throws IOException
Constructor.

Parameters:
in - input stream
Throws:
IOException - I/O exception
Method Detail

read

public void read(DataInput in)
          throws IOException
Reads the token set from the specified input.

Parameters:
in - input stream
Throws:
IOException - I/O exception

write

public void write(DataOutput out)
           throws IOException
Writes the token set to the specified output.

Parameters:
out - output stream
Throws:
IOException - I/O exception

add

public final int add(byte[] key)
Indexes the specified key and returns the offset of the added key. If the key exists already, a negative offset is returned.

Parameters:
key - key
Returns:
offset of added key, negative offset otherwise

delete

public final int delete(byte[] key)
Deletes the specified key.

Parameters:
key - key
Returns:
deleted key or 0

id

public final int id(byte[] key)
Returns the id of the specified key or 0 if key was not found.

Parameters:
key - key to be found
Returns:
id or 0 if nothing was found

key

public final byte[] key(int i)
Returns the specified key.

Parameters:
i - key index
Returns:
key

keys

public final byte[][] keys()
Returns the hash keys.

Returns:
keys

size

public final int size()
Returns number of entries.

Returns:
number of entries