package
mapreduce;
import
java.io.IOException;
import
java.util.StringTokenizer;
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;
public
class
WordCount1{
public
static
void
main(String[] args)
throws
IOException,ClassNotFoundException,InterruptedException {
Job job = Job.getInstance();
job.setJobName(
"WordCount1"
);
job.setJarByClass(WordCount1.
class
);
job.setMapperClass(doMapper.
class
);
job.setReducerClass(doReducer.
class
);
job.setOutputKeyClass(Text.
class
);
job.setOutputValueClass(IntWritable.
class
);
Path in =
new
Path(
"hdfs://localhost:9000/mymapreduce1/in/buyer_favorite1"
);
Path out =
new
Path(
"hdfs://localhost:9000/mymapreduce1/out"
);
FileInputFormat.addInputPath(job,in);
FileOutputFormat.setOutputPath(job,out);
System.exit(job.waitForCompletion(
true
)?
0
:
1
);
}
public
static
class
doMapper
extends
Mapper<Object,Text,Text,IntWritable>{
public
static
final
IntWritable one =
new
IntWritable(
1
);
public
static
Text word =
new
Text();
@Override
protected
void
map(Object key, Text value, Context context)
throws
IOException,InterruptedException {
StringTokenizer tokenizer =
new
StringTokenizer(value.toString(),
" "
);
word.set(tokenizer.nextToken());
context.write(word,one);
}
}
public
static
class
doReducer
extends
Reducer<Text,IntWritable,Text,IntWritable>{
private
IntWritable result =
new
IntWritable();
@Override
protected
void
reduce(Text key,Iterable<IntWritable> values,Context context)
throws
IOException,InterruptedException{
int
sum =
0
;
for
(IntWritable value : values){
sum += value.get();
}
result.set(sum);
context.write(key,result);
}
}
}
|
buyer_favorite1文件内容：
运行结果：
