IndexService.IColumnRecordReader.java Source code

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Here is the source code for IndexService.IColumnRecordReader.java

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/**
* Tencent is pleased to support the open source community by making TDW available.
* Copyright (C) 2014 THL A29 Limited, a Tencent company. All rights reserved.
* 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 IndexService;

import java.io.IOException;
import java.util.ArrayList;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapred.RecordReader;

import Comm.ConstVar;
import FormatStorage1.IColumnDataFile;
import FormatStorage1.IRecord;

public class IColumnRecordReader<K, V> implements RecordReader<IndexKey, IndexValue> {
    public static final Log LOG = LogFactory.getLog(IColumnRecordReader.class);

    Configuration conf;

    int currentline = -1;

    int beginLine = 0;
    int endLine = 0;

    IColumnDataFile icdf = null;

    IRecord record;
    ArrayList<Integer> indexkeys;
    int fileindex;

    IColumnRecordReader(Configuration conf, IColumnInputSplit split) throws IOException {

        this.conf = conf;

        String[] indexfilemap = conf.getStrings(ConstVar.HD_index_filemap);
        String splitfilename = split.getPath().toString();
        for (int i = 0; i < indexfilemap.length; i++) {
            if (splitfilename.endsWith(indexfilemap[i])) {
                this.fileindex = i;
                break;
            }
        }

        indexkeys = new ArrayList<Integer>();
        String idss = conf.get("index.ids");

        String[] strs = idss.split(",");
        for (int i = 0; i < strs.length; i++) {
            indexkeys.add(Integer.parseInt(strs[i]));
        }

        icdf = new IColumnDataFile(conf);

        icdf.open(split.getPath().toString());

        if (split.wholefileASasplit) {
            this.beginLine = 0;
            this.endLine = icdf.recnum() - 1;
        } else {
            beginLine = split.beginline;
            endLine = split.beginline + split.recnum - 1;
        }

        currentline = beginLine;
        icdf.seek(currentline);
        record = icdf.getIRecordObj();

    }

    @Override
    public boolean next(IndexKey key, IndexValue value) throws IOException {

        if (currentline > endLine) {
            return false;
        }

        label: while (true) {
            key.reset();
            icdf.next(record);

            for (Integer idx : indexkeys) {
                IRecord.IFValue fv = record.getByIdx(idx);
                if (fv == null) {
                    currentline++;
                    continue label;
                }
                key.addfv(fv);
            }

            value.setFileindex(this.fileindex);
            value.setRowid(currentline);

            currentline++;
            return true;
        }
    }

    @Override
    public void close() throws IOException {
        icdf.close();
    }

    @Override
    public IndexKey createKey() {
        return new IndexKey();
    }

    @Override
    public IndexValue createValue() {
        return new IndexValue();
    }

    @Override
    public long getPos() throws IOException {
        return currentline;
    }

    @Override
    public float getProgress() throws IOException {
        return (float) (currentline - this.beginLine) / (float) (this.endLine - this.beginLine + 1);
    }
}