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 com.pinterest.terrapin.hadoop; import static org.junit.Assert.assertEquals; import com.pinterest.terrapin.Constants; import com.google.common.collect.Lists; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.hbase.HColumnDescriptor; import org.apache.hadoop.hbase.KeyValue; import org.apache.hadoop.hbase.io.hfile.CacheConfig; import org.apache.hadoop.hbase.io.hfile.HFile; import org.apache.hadoop.hbase.io.hfile.HFileScanner; import org.apache.hadoop.hbase.regionserver.StoreFile; import org.apache.hadoop.io.BytesWritable; import org.apache.hadoop.mapreduce.RecordWriter; import org.junit.After; import org.junit.Before; import org.junit.Test; import java.io.File; import java.io.IOException; import java.util.List; public class HFileRecordWriterTest { private File tempFile; @Before public void setUp() throws IOException { tempFile = File.createTempFile("hfile", Integer.toString((int) Math.random())); } @Test public void testWrite() throws Exception { Configuration conf = new Configuration(); HColumnDescriptor columnDescriptor = new HColumnDescriptor(); // Disable block cache to ensure it reads the actual file content. columnDescriptor.setBlockCacheEnabled(false); FileSystem fs = FileSystem.get(conf); int blockSize = conf.getInt(Constants.HFILE_BLOCKSIZE, 16384); final StoreFile.Writer writer = new StoreFile.WriterBuilder(conf, new CacheConfig(conf, columnDescriptor), fs, blockSize).withFilePath(new Path(tempFile.toURI())).build(); /* Create our RecordWriter */ RecordWriter<BytesWritable, BytesWritable> hfileWriter = new HFileRecordWriter(writer); List<String> keys = Lists.newArrayList(); List<String> values = Lists.newArrayList(); for (int i = 0; i < 100; ++i) { String key = String.format("%03d", i); String val = "value " + i; keys.add(key); values.add(val); hfileWriter.write(new BytesWritable(key.getBytes()), new BytesWritable(val.getBytes())); } /* This internally closes the StoreFile.Writer */ hfileWriter.close(null); HFile.Reader reader = HFile.createReader(fs, new Path(tempFile.toURI()), new CacheConfig(conf, columnDescriptor)); HFileScanner scanner = reader.getScanner(false, false, false); boolean valid = scanner.seekTo(); List<String> gotKeys = Lists.newArrayListWithCapacity(keys.size()); List<String> gotValues = Lists.newArrayListWithCapacity(values.size()); while (valid) { KeyValue keyValue = scanner.getKeyValue(); gotKeys.add(new String(keyValue.getRow())); gotValues.add(new String(keyValue.getValue())); valid = scanner.next(); } assertEquals(keys, gotKeys); assertEquals(values, gotValues); reader.close(); } @After public void cleanUp() { if (tempFile != null) { tempFile.delete(); } } }