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

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Here is the source code for org.cloudata.core.parallel.hadoop.TableScanCellReader.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.ScanCell;
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 TableScanCellReader implements RecordReader<Row.Key, Writable> {
    static final Logger LOG = Logger.getLogger(TableScanCellReader.class.getName());
    private TableScanner scanner;
    private int readRowCount;
    private int TOTAL_ROW = 1000000;
    private boolean end = false;
    private ScanCell scanCell;
    private long totalScanTime;
    private JobConf jobConf;

    private boolean skipError = false;

    private Reporter reporter;

    public TableScanCellReader(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();
        Row.Key startRowKey = rowFilter.getStartRowKey();

        reporter.setStatus(inputTableInfo.getTableName() + ":" + rowFilter.getStartRowKey() + " ~ "
                + rowFilter.getEndRowKey());

        CTable ctable = CTable.openTable(conf, inputTableInfo.getTableName());
        long startTime = System.currentTimeMillis();
        try {
            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 + "," + e.getMessage());
            if (skipError) {
                reporter.setStatus(
                        "Error while scanner open:startRowKey=" + startRowKey + ", endRowKey=" + e.getMessage());
                reporter.incrCounter("cloudata", "error", 1);
                return;
            } else {
                throw e;
            }
        }

        try {
            // Tablet?  ?  row .
            scanCell = scanner.next();
            if (scanCell == null) {
                end = true;
                scanner.close();
                scanner = null;
                return;
            }
            if (!startRowKey.equals(Row.Key.MIN_KEY)) {
                Row.Key firstRow = scanCell.getRowKey();

                while (firstRow.equals(scanCell.getRowKey())) {
                    scanCell = scanner.next();
                    if (scanCell == null) {
                        end = true;
                        scanner.close();
                        scanner = null;
                        break;
                    }
                }
            }

            totalScanTime += (System.currentTimeMillis() - startTime);
        } catch (IOException e) {
            if (scanner == null) {
                scanner.close();
                scanner = null;
            }
            LOG.error("Error while skip first row:startRowKey=" + startRowKey + "," + e.getMessage());
            if (skipError) {
                reporter.setStatus(
                        "Error while skip first row:startRowKey=" + startRowKey + ", endRowKey=" + e.getMessage());
                reporter.incrCounter("cloudata", "error", 1);
                return;
            } else {
                throw e;
            }
        }
    }

    public void close() throws IOException {
        LOG.debug("Total Scan Time:" + totalScanTime + " ms");
        if (scanner != null) {
            scanner.close();
            scanner = null;
        }
    }

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

    @Override
    public ScanCell createValue() {
        ScanCell scanCell = new ScanCell();
        return scanCell;
    }

    @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 {
        boolean hasMore = (scanCell != null);
        if (!end && hasMore) {
            Row.Key rowKey = scanCell.getRowKey();
            key.set(rowKey.getBytes());

            readRowCount++;

            ScanCell result = (ScanCell) value;
            result.setRowKey(rowKey);
            result.setColumnName(scanCell.getColumnName());
            result.setCellKey(scanCell.getCellKey());
            result.setCellValue(scanCell.getCellValue());

            try {
                long startTime = System.currentTimeMillis();
                scanCell = scanner.next();
                totalScanTime += (System.currentTimeMillis() - startTime);
            } catch (IOException e) {
                end = true;
                LOG.error("Error while scanner.next():" + e.getMessage());
                reporter.setStatus("Error while scanner.next():" + e.getMessage());
                if (skipError) {
                    reporter.incrCounter("cloudata", "error", 1);
                    return false;
                } else {
                    throw e;
                }
            }
        }
        end = !hasMore;

        if (!hasMore) {
            LOG.info("end of data");
            if (scanner != null) {
                scanner.close();
                scanner = null;
            }
        }
        return hasMore;
    }
}