org.apache.hadoop.hbase.regionserver.MutableCellSetSegment.java Source code

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Here is the source code for org.apache.hadoop.hbase.regionserver.MutableCellSetSegment.java

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/**
 *
 * 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.hadoop.hbase.regionserver;

import java.util.Iterator;
import java.util.SortedSet;

import org.apache.commons.logging.Log;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellComparator;
import org.apache.hadoop.hbase.classification.InterfaceAudience;

/**
 * This mutable store segment encapsulates a mutable cell set and its respective memory allocation
 * buffers (MSLAB).
 */
@InterfaceAudience.Private
final class MutableCellSetSegment extends MutableSegment {

    private volatile CellSet cellSet;
    private final CellComparator comparator;

    // Instantiate objects only using factory
    MutableCellSetSegment(CellSet cellSet, MemStoreLAB memStoreLAB, long size, CellComparator comparator) {
        super(memStoreLAB, size);
        this.cellSet = cellSet;
        this.comparator = comparator;
    }

    @Override
    public SegmentScanner getSegmentScanner(long readPoint) {
        return new MutableCellSetSegmentScanner(this, readPoint);
    }

    @Override
    public boolean isEmpty() {
        return getCellSet().isEmpty();
    }

    @Override
    public int getCellsCount() {
        return getCellSet().size();
    }

    @Override
    public long add(Cell cell) {
        boolean succ = getCellSet().add(cell);
        long s = AbstractMemStore.heapSizeChange(cell, succ);
        updateMetaInfo(cell, s);
        // In no tags case this NoTagsKeyValue.getTagsLength() is a cheap call.
        // When we use ACL CP or Visibility CP which deals with Tags during
        // mutation, the TagRewriteCell.getTagsLength() is a cheaper call. We do not
        // parse the byte[] to identify the tags length.
        if (cell.getTagsLength() > 0) {
            tagsPresent = true;
        }
        return s;
    }

    @Override
    public long rollback(Cell cell) {
        Cell found = get(cell);
        if (found != null && found.getSequenceId() == cell.getSequenceId()) {
            long sz = AbstractMemStore.heapSizeChange(cell, true);
            remove(cell);
            incSize(-sz);
            return sz;
        }
        return 0;
    }

    @Override
    public Cell getFirstAfter(Cell cell) {
        SortedSet<Cell> snTailSet = tailSet(cell);
        if (!snTailSet.isEmpty()) {
            return snTailSet.first();
        }
        return null;
    }

    @Override
    public void dump(Log log) {
        for (Cell cell : getCellSet()) {
            log.debug(cell);
        }
    }

    @Override
    public SortedSet<Cell> tailSet(Cell firstCell) {
        return getCellSet().tailSet(firstCell);
    }

    @Override
    public CellSet getCellSet() {
        return cellSet;
    }

    @Override
    public CellComparator getComparator() {
        return comparator;
    }

    //*** Methods for MemStoreSegmentsScanner
    public Cell last() {
        return getCellSet().last();
    }

    public Iterator<Cell> iterator() {
        return getCellSet().iterator();
    }

    public SortedSet<Cell> headSet(Cell firstKeyOnRow) {
        return getCellSet().headSet(firstKeyOnRow);
    }

    public int compare(Cell left, Cell right) {
        return getComparator().compare(left, right);
    }

    public int compareRows(Cell left, Cell right) {
        return getComparator().compareRows(left, right);
    }

    private Cell get(Cell cell) {
        return getCellSet().get(cell);
    }

    private boolean remove(Cell e) {
        return getCellSet().remove(e);
    }

    // methods for tests
    @Override
    Cell first() {
        return this.getCellSet().first();
    }

}