org.cloudata.examples.web.WebKeyRangePartitioner.java Source code

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Here is the source code for org.cloudata.examples.web.WebKeyRangePartitioner.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.cloudata.examples.web;

import java.io.UnsupportedEncodingException;
import java.util.SortedSet;
import java.util.TreeSet;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Partitioner;
import org.cloudata.core.client.CTable;
import org.cloudata.core.client.Row;
import org.cloudata.core.common.conf.CloudataConf;
import org.cloudata.core.parallel.hadoop.AbstractTabletInputFormat;
import org.cloudata.core.tablet.TabletInfo;

public class WebKeyRangePartitioner implements Partitioner<WritableComparable, Writable> {
    public static final Log LOG = LogFactory.getLog(WebKeyRangePartitioner.class.getName());

    private SortedSet<RowKeyItem> tabletInfoSet = new TreeSet<RowKeyItem>();
    private Exception confException;

    int count = 0;

    public int getPartition(WritableComparable key, Writable value, int numPartitions) {
        if (confException != null) {
            LOG.error(confException.getMessage(), confException);
            return -1;
        }

        if (numPartitions != tabletInfoSet.size()) {
            LOG.error(
                    "tablet count(" + tabletInfoSet.size() + ") not equals numPartitions (" + numPartitions + ")");
            return -1;
        }

        if (tabletInfoSet.size() == 0) {
            LOG.error("tablet partition size is zero");
            return -1;
        }
        int partitionNumber = 0;
        Text tKey = (Text) key;

        Row.Key rowKey;

        int keyIndex = tKey.find("\t");
        if (keyIndex < 0) {
            LOG.error("invalid value:" + tKey);
            rowKey = Row.Key.MAX_KEY;
        } else {
            rowKey = new Row.Key(tKey.getBytes(), 0, keyIndex);
        }

        SortedSet<RowKeyItem> tailSet = tabletInfoSet.tailSet(new RowKeyItem(rowKey, 0));
        RowKeyItem item = null;
        if (tailSet.size() > 0) {
            item = tailSet.first();
            partitionNumber = item.index;
        } else {
            item = tabletInfoSet.last();
            partitionNumber = item.index;
        }

        if (partitionNumber >= numPartitions) {
            LOG.info("Partition Number is : " + partitionNumber + ", numPartitions : " + numPartitions
                    + ", Row.Key : " + key.toString());
            partitionNumber = numPartitions - 1;
        }
        //LOG.info("tablet partition num:" + partitionNumber);
        count++;
        if (count % 5000 == 0) {
            try {
                System.out.println("Partitioned:" + new String(rowKey.getBytes(), "EUC-KR") + ","
                        + new String(item.rowKey.getBytes(), "EUC-KR"));
            } catch (UnsupportedEncodingException e) {

            }
        }
        return partitionNumber;
    }

    public void configure(JobConf jobConf) {
        String tableName = jobConf.get(AbstractTabletInputFormat.OUTPUT_TABLE);
        try {
            CTable ctable = CTable.openTable(new CloudataConf(), tableName);
            TabletInfo[] tabletInfos = ctable.listTabletInfos();
            if (tabletInfos == null) {
                confException = new Exception("No Tablets in table [" + tableName + "]");
                LOG.error("No Tablets in table [" + tableName + "]");
                return;
            }
            for (int i = 0; i < tabletInfos.length; i++) {
                LOG.info("Add endRowKey: " + new String(tabletInfos[i].getEndRowKey().getBytes(), "EUC-KR"));
                tabletInfoSet.add(new RowKeyItem(tabletInfos[i].getEndRowKey(), i));
            }
            if (tabletInfoSet.size() == 0) {
                confException = new Exception("No Key raneg in table [" + tableName + "]");
                LOG.error("No Key raneg in table [" + tableName + "]");
            }
        } catch (Exception e) {
            LOG.error("KeyRangePartitioner config error:" + tableName + "," + e.getMessage());
            e.printStackTrace(System.out);
            confException = e;
        }
    }

    static class RowKeyItem implements Comparable<RowKeyItem> {
        Row.Key rowKey;
        int index;

        RowKeyItem(Row.Key rowKey, int index) {
            this.rowKey = rowKey;
            this.index = index;
        }

        public int compareTo(RowKeyItem item) {
            return rowKey.compareTo(item.rowKey);
        }
    }
}