Java tutorial
/* * 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.apache.kylin.job.hadoop.invertedindex; import java.io.IOException; import java.util.Iterator; import org.apache.commons.io.IOUtils; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.hbase.io.ImmutableBytesWritable; import org.apache.hadoop.io.SequenceFile; import org.apache.hadoop.io.SequenceFile.Reader; import org.apache.kylin.common.KylinConfig; import org.apache.kylin.engine.mr.HadoopUtil; import org.apache.kylin.invertedindex.IIInstance; import org.apache.kylin.invertedindex.IIManager; import org.apache.kylin.invertedindex.index.RawTableRecord; import org.apache.kylin.invertedindex.index.Slice; import org.apache.kylin.invertedindex.index.TableRecord; import org.apache.kylin.invertedindex.index.TableRecordInfo; import org.apache.kylin.invertedindex.model.IIKeyValueCodec; import org.apache.kylin.invertedindex.model.IIRow; /** * @author yangli9 */ public class IICLI { public static void main(String[] args) throws IOException { Configuration hconf = HadoopUtil.getCurrentConfiguration(); IIManager mgr = IIManager.getInstance(KylinConfig.getInstanceFromEnv()); String iiName = args[0]; IIInstance ii = mgr.getII(iiName); String path = args[1]; System.out.println("Reading from " + path + " ..."); TableRecordInfo info = new TableRecordInfo(ii.getFirstSegment()); IIKeyValueCodec codec = new IIKeyValueCodec(info.getDigest()); int count = 0; for (Slice slice : codec.decodeKeyValue(readSequenceKVs(hconf, path))) { for (RawTableRecord rec : slice) { System.out.printf(new TableRecord(rec, info).toString()); count++; } } System.out.println("Total " + count + " records"); } public static Iterable<IIRow> readSequenceKVs(Configuration hconf, String path) throws IOException { final Reader reader = new Reader(hconf, SequenceFile.Reader.file(new Path(path))); return new Iterable<IIRow>() { @Override public Iterator<IIRow> iterator() { return new Iterator<IIRow>() { ImmutableBytesWritable k = new ImmutableBytesWritable(); ImmutableBytesWritable v = new ImmutableBytesWritable(); IIRow pair = new IIRow(k, v, null); @Override public boolean hasNext() { boolean hasNext = false; try { hasNext = reader.next(k, v); } catch (IOException e) { throw new RuntimeException(e); } finally { if (hasNext == false) { IOUtils.closeQuietly(reader); } } return hasNext; } @Override public IIRow next() { return pair; } @Override public void remove() { throw new UnsupportedOperationException(); } }; } }; } }