org.cloudata.core.parallel.hadoop.TableRowRecordReader.java Source code

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Here is the source code for org.cloudata.core.parallel.hadoop.TableRowRecordReader.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.core.parallel.hadoop;

import java.io.IOException;

import org.apache.hadoop.io.Writable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.RecordReader;
import org.apache.hadoop.mapred.Reporter;
import org.apache.log4j.Logger;
import org.cloudata.core.client.CTable;
import org.cloudata.core.client.Row;
import org.cloudata.core.client.RowFilter;
import org.cloudata.core.client.scanner.ScannerFactory;
import org.cloudata.core.client.scanner.TableScanner;
import org.cloudata.core.common.conf.CloudataConf;

/**
 * @author jindolk
 *
 */
public class TableRowRecordReader implements RecordReader<Row.Key, Writable> {
    static final Logger LOG = Logger.getLogger(TableRowRecordReader.class.getName());
    private TableScanner scanner;
    private int readRowCount;
    private int TOTAL_ROW = 1000000;
    private boolean end = false;

    private Row.Key startRowKey;
    private Row.Key endRowKey;

    private JobConf jobConf;

    private boolean skipError = false;

    private Reporter reporter;

    public TableRowRecordReader(JobConf jobConf, CloudataConf conf, TableSplit tableSplit, Reporter reporter)
            throws IOException {
        this.jobConf = jobConf;
        this.reporter = reporter;
        this.skipError = jobConf.getBoolean(AbstractTabletInputFormat.SKIP_ERROR, false);

        RowFilter rowFilter = tableSplit.getRowFilter();
        InputTableInfo inputTableInfo = tableSplit.getInputTableInfo();

        this.startRowKey = rowFilter.getStartRowKey();
        this.endRowKey = rowFilter.getEndRowKey();

        LOG.info("TableSplit: " + inputTableInfo.getTableName() + ":" + startRowKey + " ~ " + endRowKey);
        if (reporter != null) {
            reporter.setStatus(inputTableInfo.getTableName() + ":" + startRowKey + " ~ " + endRowKey);
        }

        CTable ctable = CTable.openTable(conf, inputTableInfo.getTableName());
        try {
            this.scanner = ScannerFactory.openScanner(ctable, rowFilter, TableScanner.SCANNER_OPEN_TIMEOUT);
        } catch (IOException e) {
            if (this.scanner != null) {
                this.scanner.close();
            }
            end = true;
            LOG.error("Error while scanner open:startRowKey=" + startRowKey + ", endRowKey=" + endRowKey, e);
            if (skipError) {
                reporter.setStatus("Error while scanner open:startRowKey=" + startRowKey + ", endRowKey="
                        + endRowKey + "," + e.getMessage());
                reporter.incrCounter("cloudata", "error", 1);
                return;
            } else {
                throw e;
            }
        }

        //If Tablet isn't first tablet, skip first row.
        if (!startRowKey.equals(tableSplit.getJobStartRowKey())) {
            try {
                Row row = scanner.nextRow();
                if (row == null) {
                    end = true;
                    return;
                }
            } catch (IOException e) {
                end = true;
                LOG.error("Error while scanner.nextRow():startRowKey=" + startRowKey + ", endRowKey=" + endRowKey,
                        e);
                if (skipError) {
                    reporter.setStatus("Error while scanner.nextRow():startRowKey=" + startRowKey + ", endRowKey="
                            + endRowKey + "," + e.getMessage());
                    reporter.incrCounter("cloudata", "error", 1);
                    return;
                } else {
                    throw e;
                }
            }
        }
    }

    @Override
    public void close() throws IOException {
        end = true;
        if (scanner != null) {
            scanner.close();
            scanner = null;
        }
    }

    @Override
    public Row.Key createKey() {
        return new Row.Key();
    }

    @Override
    public Writable createValue() {
        Row row = new Row();
        return row;
    }

    @Override
    public long getPos() {
        return readRowCount;
    }

    @Override
    public float getProgress() {
        //  TODO tablet?  row    
        if (end) {
            return 1.0f;
        } else {
            float progress = (float) readRowCount / (float) TOTAL_ROW;
            if (progress >= 1.0) {
                return 0.98f;
            } else {
                return progress;
            }
        }
    }

    @Override
    public boolean next(Row.Key key, Writable value) throws IOException {
        if (end) {
            return false;
        }
        Row row = null;
        try {
            row = scanner.nextRow();
        } catch (IOException e) {
            end = true;
            LOG.error("nextRow error:range=" + startRowKey + "," + endRowKey + "," + e.getMessage(), e);
            if (skipError) {
                reporter.setStatus("Error while nextRow:startRowKey=" + startRowKey + ", endRowKey=" + endRowKey
                        + "," + e.getMessage());
                reporter.incrCounter("cloudata", "error", 1);
                return false;
            } else {
                throw e;
            }
        }

        boolean hasMore = (row != null);

        if (!end && hasMore) {
            readRowCount++;
            Row.Key rowKey = row.getKey();

            key.set(rowKey.getBytes());

            Row result = (Row) value;

            result.setKey(rowKey);
            result.setAllCells(row.getAllCells());
        }
        end = !hasMore;
        if (!hasMore) {
            if (scanner != null) {
                scanner.close();
                scanner = null;
            }
        }
        return hasMore;
    }

}