Java tutorial
/* * Copyright 2010-2011 the original author or authors. * * 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 cn.lhfei.hadoop.ch04; import java.io.IOException; import java.net.URI; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IOUtils; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.MapFile; import org.apache.hadoop.io.SequenceFile.Writer; import org.apache.hadoop.io.Text; /** * @version 0.1 * * @author Hefei Li * * @since Oct 30, 2014 */ public class MapFileWriteDemo { private static final String[] DATA = { "One, two, buckle my shoe", "Three, four, shut the door", "Five, six, pick up sticks", "Seven, eight, lay them straight", "Nine, ten, a big fat hen" }; public static void main(String[] args) { String uri = args[0]; Configuration conf = new Configuration(); FileSystem fs = null; IntWritable key = new IntWritable(); Text value = new Text(); MapFile.Writer writer = null; try { fs = FileSystem.get(URI.create(uri), conf); /*writer = new MapFile.Writer(conf, fs, uri, key.getClass(), value.getClass());*/ writer = new MapFile.Writer(conf, new Path(uri), Writer.keyClass(key.getClass()), Writer.valueClass(value.getClass())); for (int i = 0; i < 1024; i++) { key.set(i + 1); value.set(DATA[i % DATA.length]); writer.append(key, value); } } catch (IOException e) { e.printStackTrace(); } finally { IOUtils.closeStream(writer); } } }