DOC HOME SITE MAP MAN PAGES GNU INFO SEARCH PRINT BOOK
 
Berkeley DB
version 4.4.20

com.sleepycat.bind.tuple
Class TupleTupleKeyCreator

java.lang.Object
  extended bycom.sleepycat.bind.tuple.TupleBase
      extended bycom.sleepycat.bind.tuple.TupleTupleKeyCreator
All Implemented Interfaces:
SecondaryKeyCreator
Direct Known Subclasses:
TupleTupleMarshalledKeyCreator

public abstract class TupleTupleKeyCreator
extends TupleBase
implements SecondaryKeyCreator

An abstract key creator that uses a tuple key and a tuple data entry. This class takes care of converting the key and data entry to/from TupleInput and TupleOutput objects.


Constructor Summary
TupleTupleKeyCreator()
          Creates a tuple-tuple key creator.
 
Method Summary
 boolean createSecondaryKey(SecondaryDatabase db, DatabaseEntry primaryKeyEntry, DatabaseEntry dataEntry, DatabaseEntry indexKeyEntry)
          Creates a secondary key entry, given a primary key and data entry.
abstract  boolean createSecondaryKey(TupleInput primaryKeyInput, TupleInput dataInput, TupleOutput indexKeyOutput)
          Creates the index key from primary key tuple and data tuple.
 boolean nullifyForeignKey(SecondaryDatabase db, DatabaseEntry dataEntry)
           
 boolean nullifyForeignKey(TupleInput dataInput, TupleOutput dataOutput)
          Clears the index key in the tuple data entry.
 
Methods inherited from class com.sleepycat.bind.tuple.TupleBase
entryToInput, getTupleBufferSize, getTupleOutput, inputToEntry, newOutput, newOutput, outputToEntry, setTupleBufferSize
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

TupleTupleKeyCreator

public TupleTupleKeyCreator()
Creates a tuple-tuple key creator.

Method Detail

createSecondaryKey

public boolean createSecondaryKey(SecondaryDatabase db,
                                  DatabaseEntry primaryKeyEntry,
                                  DatabaseEntry dataEntry,
                                  DatabaseEntry indexKeyEntry)
                           throws DatabaseException
Description copied from interface: SecondaryKeyCreator
Creates a secondary key entry, given a primary key and data entry.

Specified by:
createSecondaryKey in interface SecondaryKeyCreator
Parameters:
db - the database to which the secondary key will be added.

primaryKeyEntry - the primary key entry. This parameter must not be modified by this method.

dataEntry - the primary data entry. This parameter must not be modified by this method.

indexKeyEntry - the secondary key created by this method.

Returns:
true if a key was created, or false to indicate that the key is not present.

Throws:
DatabaseException - if an error occurs attempting to create the secondary key.

nullifyForeignKey

public boolean nullifyForeignKey(SecondaryDatabase db,
                                 DatabaseEntry dataEntry)
                          throws DatabaseException
Throws:
DatabaseException

createSecondaryKey

public abstract boolean createSecondaryKey(TupleInput primaryKeyInput,
                                           TupleInput dataInput,
                                           TupleOutput indexKeyOutput)
Creates the index key from primary key tuple and data tuple.

Parameters:
primaryKeyInput - is the TupleInput for the primary key entry.
dataInput - is the TupleInput for the data entry.
indexKeyOutput - is the destination index key tuple.
Returns:
true if a key was created, or false to indicate that the key is not present.

nullifyForeignKey

public boolean nullifyForeignKey(TupleInput dataInput,
                                 TupleOutput dataOutput)
Clears the index key in the tuple data entry. The dataInput should be read and then written to the dataOutput, clearing the index key in the process.

The secondary key should be output or removed by this method such that createSecondaryKey(com.sleepycat.db.SecondaryDatabase, com.sleepycat.db.DatabaseEntry, com.sleepycat.db.DatabaseEntry, com.sleepycat.db.DatabaseEntry) will return false. Other fields in the data object should remain unchanged.

Parameters:
dataInput - is the TupleInput for the data entry.
dataOutput - is the destination TupleOutput.
Returns:
true if the key was cleared, or false to indicate that the key is not present and no change is necessary.

Berkeley DB
version 4.4.20

Copyright (c) 1996-2005 Sleepycat Software, Inc. - All rights reserved.