com.nesscomputing.hbase.spill.SpilledFile.java Source code

Introduction

Here is the source code for com.nesscomputing.hbase.spill.SpilledFile.java

Source

/**
 * Copyright (C) 2012 Ness Computing, Inc.
 *
 * Licensed 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 com.nesscomputing.hbase.spill;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import javax.annotation.Nonnull;

import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import com.google.common.io.Closeables;

import com.nesscomputing.logging.Log;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;
import org.apache.hadoop.hbase.client.Put;

public class SpilledFile {
    private static final Log LOG = Log.findLog();

    private final File file;

    private final int version;
    private final int elements;
    private final long timestamp;

    SpilledFile(@Nonnull final File file) throws IOException {
        Preconditions.checkNotNull(file, "the file must not be null!");

        this.file = file;

        InputStream is = null;

        try {
            is = new FileInputStream(file);
            version = BinaryConverter.readInt(is);
            elements = BinaryConverter.readInt(is);
            timestamp = BinaryConverter.readLong(is);

            LOG.trace("Opened spill file %s : v%d, count: %d, age: %d", file.getAbsolutePath(), version, elements,
                    timestamp);
        } finally {
            Closeables.closeQuietly(is);
        }
    }

    public String getName() {
        return file.getName();
    }

    public int getVersion() {
        return version;
    }

    public int getElements() {
        return elements;
    }

    public long getTimestamp() {
        return timestamp;
    }

    public List<Put> load() throws IOException {
        InputStream is = null;

        final ImmutableList.Builder<Put> builder = ImmutableList.builder();

        try {
            is = new BufferedInputStream(new FileInputStream(file));

            final int skippedBytes = 4 + 4 + 8; // int, int, long
            Preconditions.checkState(skippedBytes == is.skip(skippedBytes),
                    "skipped byte mismatch (you are in trouble...)");

            Put put = null;

            while ((put = BinaryConverter.PUT_READ_FUNCTION.apply(is)) != null) {
                builder.add(put);
            }

            final List<Put> result = builder.build();
            Preconditions.checkState(result.size() == elements,
                    "The preamble reported %d elements, but %d were found!", elements, result.size());
            return result;
        } finally {
            Closeables.closeQuietly(is);
        }
    }

    @Override
    public boolean equals(final Object other) {
        if (!(other instanceof SpilledFile)) {
            return false;
        }
        final SpilledFile castOther = (SpilledFile) other;
        return new EqualsBuilder().append(file, castOther.file).append(version, castOther.version)
                .append(elements, castOther.elements).append(timestamp, castOther.timestamp).isEquals();
    }

    private transient int hashCode;

    @Override
    public int hashCode() {
        if (hashCode == 0) {
            hashCode = new HashCodeBuilder().append(file).append(version).append(elements).append(timestamp)
                    .toHashCode();
        }
        return hashCode;
    }

    private transient String toString;

    @Override
    public String toString() {
        if (toString == null) {
            toString = new ToStringBuilder(this).append("file", file).append("version", version)
                    .append("elements", elements).append("timestamp", timestamp).toString();
        }
        return toString;
    }

}