一、配置文件
1.core-site.xml
<configuration> <property> <name>fs.defaultFS</name> <value>hdfs://www.node1.com:9000</value> </property> </configuration>
2、hdfs-site.xml
<configuration> <property> <name>dfs.replication</name> <value>2</value> </property> </configuration>
3、yarn-site.xml
<property> <name>yarn.resourcemanager.hostname</name> <value>www.node1.com</value> </property> <property> <name>yarn.nodemanager.aux-services</name> <value>mapreduce_shuffle</value> </property> </configuration>
4、slaves
www.node2.com
www.node3.com
二、建立本地连接
三、创建MapReduceProject
1、File -- new - Other --MapReduceProject
2、建立测试文件
import java.io.IOException; import java.util.StringTokenizer; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.IntWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.Mapper; import org.apache.hadoop.mapreduce.Reducer; import org.apache.hadoop.mapreduce.lib.input.FileInputFormat; import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; import org.apache.hadoop.util.GenericOptionsParser; public class WordCount { public static class TokenizerMapper extends Mapper<Object, Text, Text, IntWritable>{ private final static IntWritable one = new IntWritable(1); private Text word = new Text(); public void map(Object key, Text value, Context context ) throws IOException, InterruptedException { StringTokenizer itr = new StringTokenizer(value.toString()); while (itr.hasMoreTokens()) { word.set(itr.nextToken()); context.write(word, one); } } } public static class IntSumReducer extends Reducer<Text,IntWritable,Text,IntWritable> { private IntWritable result = new IntWritable(); public void reduce(Text key, Iterable<IntWritable> values, Context context ) throws IOException, InterruptedException { int sum = 0; for (IntWritable val : values) { sum += val.get(); } result.set(sum); context.write(key, result); } } public static void main(String[] args) throws Exception { Configuration conf = new Configuration(); String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs(); if (otherArgs.length != 2) { System.err.println(otherArgs.length); System.err.println("Usage: wordcount <in> <out>"); System.exit(2); } System.out.println(otherArgs[0]); System.out.println(otherArgs[1]); Job job = new Job(conf, "word count"); job.setJarByClass(WordCount.class); job.setMapperClass(TokenizerMapper.class); job.setCombinerClass(IntSumReducer.class); job.setReducerClass(IntSumReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(IntWritable.class); FileInputFormat.addInputPath(job, new Path(otherArgs[0])); FileOutputFormat.setOutputPath(job, new Path(otherArgs[1])); System.exit(job.waitForCompletion(true) ? 0 : 1); } }
3、run configuration
hdfs://www.node1.com:9000/usr/wc hdfs://www.node1.com:9000/usr/wc/output
4、run
5、part-r-00000
apple 2 banana 1 cat 1 dog 1 hadoop 1 hadpp 1 hello 1 mapreduce 1 name 1 world 1 yarn 2
6、wc.txt
hadoop hello
hadpp world
apple dog
banana cat
mapreduce name
yarn
apple
yarn