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

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Here is the source code for org.apache.tajo.tuple.offheap.OffHeapMemory.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 com.google.common.base.Preconditions;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tajo.util.Deallocatable;
import org.apache.tajo.util.FileUtil;
import org.apache.tajo.util.UnsafeUtil;
import sun.misc.Unsafe;
import sun.nio.ch.DirectBuffer;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

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

    protected static final Unsafe UNSAFE = UnsafeUtil.unsafe;

    protected ByteBuffer buffer;
    protected int memorySize;
    protected ResizableLimitSpec limitSpec;
    protected long address;

    @VisibleForTesting
    protected OffHeapMemory(ByteBuffer buffer, ResizableLimitSpec limitSpec) {
        this.buffer = buffer;
        this.address = ((DirectBuffer) buffer).address();
        this.memorySize = buffer.limit();
        this.limitSpec = limitSpec;
    }

    public OffHeapMemory(ResizableLimitSpec limitSpec) {
        this(ByteBuffer.allocateDirect((int) limitSpec.initialSize()).order(ByteOrder.nativeOrder()), limitSpec);
    }

    public long address() {
        return address;
    }

    public long size() {
        return memorySize;
    }

    public void resize(int newSize) {
        Preconditions.checkArgument(newSize > 0, "Size must be greater than 0 bytes");

        if (newSize > limitSpec.limit()) {
            throw new RuntimeException("Resize cannot exceed the size limit");
        }

        if (newSize < memorySize) {
            LOG.warn("The size reduction is ignored.");
        }

        int newBlockSize = UnsafeUtil.alignedSize(newSize);
        ByteBuffer newByteBuf = ByteBuffer.allocateDirect(newBlockSize);
        long newAddress = ((DirectBuffer) newByteBuf).address();

        UNSAFE.copyMemory(this.address, newAddress, memorySize);

        UnsafeUtil.free(buffer);
        this.memorySize = newSize;
        this.buffer = newByteBuf;
        this.address = newAddress;
    }

    public java.nio.Buffer nioBuffer() {
        return (ByteBuffer) buffer.position(0).limit(memorySize);
    }

    @Override
    public void release() {
        UnsafeUtil.free(this.buffer);
        this.buffer = null;
        this.address = 0;
        this.memorySize = 0;
    }

    public String toString() {
        return "memory=" + FileUtil.humanReadableByteCount(memorySize, false) + "," + limitSpec;
    }
}