/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jena.tdb.base.recordbuffer;
import org.apache.jena.tdb.base.block.Block ;
import org.apache.jena.tdb.base.page.Page ;
import org.apache.jena.tdb.base.record.RecordFactory ;
import org.apache.jena.tdb.sys.SystemTDB ;
/**
* B+Tree records nodes and hash buckets.
* Add link field to a RecordBufferPageBase
*/
public final class RecordBufferPage extends RecordBufferPageBase
{
// Why not straight to BPlusTreeRecords?
// 1 - this may be useful in its own right as a seqeunce of records on-disk.
// 2 - BPlusTreeRecords inherits from BPlusTreePage
//
// Could combine with HashBuck and just have an unused link area in a HashBucket
// To Constants
// Offsets
// final public static int COUNT = 0 ;
final public static int LINK = 4 ;
final private static int FIELD_LENGTH = SystemTDB.SizeOfInt ; // Length of the space needed here (not count)
private int link = Page.NO_ID ;
public final int getLink() { return link ; }
public void setLink(int link)
{
this.link = link ;
getBackingBlock().getByteBuffer().putInt(LINK, link) ;
}
@Override
protected void _reset(Block block)
{
super.reset(block, this.getCount()) ;
this.link = block.getByteBuffer().getInt(LINK) ;
}
public static int calcRecordSize(RecordFactory factory, int blkSize)
{ return RecordBufferPageBase.calcRecordSize(factory, blkSize, FIELD_LENGTH) ; }
public static int calcBlockSize(RecordFactory factory, int maxRec)
{ return RecordBufferPageBase.calcBlockSize(factory, maxRec, FIELD_LENGTH) ; }
/** The construction methods */
public static RecordBufferPage createBlank(Block block,RecordFactory factory)
{
int count = 0 ;
int linkId = NO_ID ;
return new RecordBufferPage(block, factory, count, linkId) ;
}
public static RecordBufferPage format(Block block, RecordFactory factory)
{
int count = block.getByteBuffer().getInt(COUNT) ;
int linkId = block.getByteBuffer().getInt(LINK) ;
return new RecordBufferPage(block, factory, count, linkId) ;
}
private RecordBufferPage(Block block, RecordFactory factory, int count, int linkId)
{
super(block, FIELD_LENGTH, factory, count) ;
this.link = linkId ;
}
@Override
public String toString()
{ return String.format("RecordBufferPage[id=%d,link=%d]: %s", getBackingBlock().getId(), getLink(), recBuff) ; }
}