Changes between Initial Version and Version 1 of Hadoop_Lab4_hello_018

Timestamp:

Mar 3, 2010, 12:14:04 PM (16 years ago)

Author:

waue

Comment:

--

Hadoop_Lab4_hello_018

@@ +1 @@
+{{{
+#!java
+import java.io.IOException;
+import java.util.Iterator;
+
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.io.LongWritable;
+import org.apache.hadoop.io.Text;
+import org.apache.hadoop.mapred.FileInputFormat;
+import org.apache.hadoop.mapred.FileOutputFormat;
+import org.apache.hadoop.mapred.JobClient;
+import org.apache.hadoop.mapred.JobConf;
+import org.apache.hadoop.mapred.MapReduceBase;
+import org.apache.hadoop.mapred.Mapper;
+import org.apache.hadoop.mapred.OutputCollector;
+import org.apache.hadoop.mapred.Reducer;
+import org.apache.hadoop.mapred.Reporter;
+import org.apache.hadoop.mapred.TextInputFormat;
+import org.apache.hadoop.mapred.TextOutputFormat;
+
+public class Hello {
+
+        public static class Map extends MapReduceBase implements
+                        Mapper<LongWritable, Text, LongWritable, Text> {
+
+                public void map(LongWritable key, Text value,
+                                OutputCollector<LongWritable, Text> output, Reporter reporter)
+                                throws IOException {
+
+                        output.collect(key, value);
+                }
+        }
+
+        public static class Reduce extends MapReduceBase implements
+                        Reducer<LongWritable, Text, LongWritable, Text> {
+                Text ret = new Text("");
+
+                public void reduce(LongWritable key, Iterator<Text> values,
+                                OutputCollector<LongWritable, Text> output, Reporter reporter)
+                                throws IOException {
+
+                        while (values.hasNext()) {
+                                ret = values.next();
+                        }
+                        output.collect(key, ret);
+                }
+        }
+
+        public static void main(String[] args) throws Exception {
+                JobConf conf = new JobConf(Hello.class);
+                conf.setJobName("Hello");
+
+                conf.setMapperClass(Map.class);
+                conf.setCombinerClass(Reduce.class);
+                conf.setReducerClass(Reduce.class);
+                conf.setMapOutputKeyClass(LongWritable.class);
+                conf.setMapOutputValueClass(Text.class);
+                conf.setOutputKeyClass(LongWritable.class);
+                conf.setOutputValueClass(Text.class);
+
+                conf.setInputFormat(TextInputFormat.class);
+                conf.setOutputFormat(TextOutputFormat.class);
+
+                FileInputFormat.setInputPaths(conf, new Path(args[0]));
+                FileOutputFormat.setOutputPath(conf, new Path(args[1]));
+
+                JobClient.runJob(conf);
+        }
+}
+
+}}}