org.apache.tajo.tuple.offheap.OffHeapRowBlock.java Source code

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Here is the source code for org.apache.tajo.tuple.offheap.OffHeapRowBlock.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.tajo.tuple.offheap;

import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tajo.catalog.Schema;
import org.apache.tajo.catalog.SchemaUtil;
import org.apache.tajo.catalog.statistics.TableStats;
import org.apache.tajo.util.Deallocatable;
import org.apache.tajo.util.FileUtil;
import org.apache.tajo.util.SizeOf;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

import static org.apache.tajo.common.TajoDataTypes.DataType;

public class OffHeapRowBlock extends OffHeapMemory implements Deallocatable {
    private static final Log LOG = LogFactory.getLog(OffHeapRowBlock.class);

    public static final int NULL_FIELD_OFFSET = -1;

    DataType[] dataTypes;

    // Basic States
    private int maxRowNum = Integer.MAX_VALUE; // optional
    private int rowNum;
    protected int position = 0;

    private OffHeapRowBlockWriter builder;

    private OffHeapRowBlock(ByteBuffer buffer, Schema schema, ResizableLimitSpec limitSpec) {
        super(buffer, limitSpec);
        initialize(schema);
    }

    public OffHeapRowBlock(Schema schema, ResizableLimitSpec limitSpec) {
        super(limitSpec);
        initialize(schema);
    }

    private void initialize(Schema schema) {
        dataTypes = SchemaUtil.toDataTypes(schema);

        this.builder = new OffHeapRowBlockWriter(this);
    }

    @VisibleForTesting
    public OffHeapRowBlock(Schema schema, int bytes) {
        this(schema, new ResizableLimitSpec(bytes));
    }

    @VisibleForTesting
    public OffHeapRowBlock(Schema schema, ByteBuffer buffer) {
        this(buffer, schema, ResizableLimitSpec.DEFAULT_LIMIT);
    }

    public void position(int pos) {
        this.position = pos;
    }

    public void clear() {
        this.position = 0;
        this.rowNum = 0;

        builder.clear();
    }

    @Override
    public ByteBuffer nioBuffer() {
        return (ByteBuffer) buffer.position(0).limit(position);
    }

    public int position() {
        return position;
    }

    public long usedMem() {
        return position;
    }

    /**
     * Ensure that this buffer has enough remaining space to add the size.
     * Creates and copies to a new buffer if necessary
     *
     * @param size Size to add
     */
    public void ensureSize(int size) {
        if (remain() - size < 0) {
            if (!limitSpec.canIncrease(memorySize)) {
                throw new RuntimeException("Cannot increase RowBlock anymore.");
            }

            int newBlockSize = limitSpec.increasedSize(memorySize);
            resize(newBlockSize);
            LOG.info("Increase DirectRowBlock to " + FileUtil.humanReadableByteCount(newBlockSize, false));
        }
    }

    public long remain() {
        return memorySize - position - builder.offset();
    }

    public int maxRowNum() {
        return maxRowNum;
    }

    public int rows() {
        return rowNum;
    }

    public void setRows(int rowNum) {
        this.rowNum = rowNum;
    }

    public boolean copyFromChannel(FileChannel channel, TableStats stats) throws IOException {
        if (channel.position() < channel.size()) {
            clear();

            buffer.clear();
            channel.read(buffer);
            memorySize = buffer.position();

            while (position < memorySize) {
                long recordPtr = address + position;

                if (remain() < SizeOf.SIZE_OF_INT) {
                    channel.position(channel.position() - remain());
                    memorySize = (int) (memorySize - remain());
                    return true;
                }

                int recordSize = UNSAFE.getInt(recordPtr);

                if (remain() < recordSize) {
                    channel.position(channel.position() - remain());
                    memorySize = (int) (memorySize - remain());
                    return true;
                }

                position += recordSize;
                rowNum++;
            }

            return true;
        } else {
            return false;
        }
    }

    public RowWriter getWriter() {
        return builder;
    }

    public OffHeapRowBlockReader getReader() {
        return new OffHeapRowBlockReader(this);
    }
}