mapreduce 自定义数据类型的简单的应用
本文以手机流量统计为例：
日志中包含下面字段
现在需要统计手机的上行数据包，下行数据包，上行总流量，下行总流量。
分析：可以以手机号为key 以上4个字段为value传传递数据。
这样则需要自己定义一个数据类型，用于封装要统计的4个字段，在map 与reduce之间传递和shuffle
注：作为key的自定义类型需要实现WritableComparable 里面的compareTo方法
作为value的自定义类 则只需实现Writable里面的方法
自定义代码如下：
/*** * MapReduce Module * * @author nele * */ public class MobileDataMapReduce extends Configured implements Tool { // map class /** * * @author nele * */ public static class MobileDataMapper extends Mapper<LongWritable, Text, Text, MobileDataWritable> { public Text outPutKey = new Text(); public MobileDataWritable outPutValue = new MobileDataWritable(); @Override public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { System.out.println(key+":"+value); String[] arr = value.toString().split("\t"); outPutKey.set(arr[1]); outPutValue.set(Long.valueOf(arr[6]), Long.valueOf(arr[7]), Long.valueOf(arr[8]), Long.valueOf(arr[9])); context.write(outPutKey, outPutValue); } } // reduce class /*** * * @author nele * */ public static class MobileDataReducer extends Reducer<Text, MobileDataWritable, Text, MobileDataWritable> { private Text outPutKey = new Text(); private MobileDataWritable outPutValue = new MobileDataWritable(); @Override public void reduce(Text key, Iterable<MobileDataWritable> values, Context context) throws IOException, InterruptedException { long upPackNum = 0; long downPackNum = 0; long upPayLoad = 0; long downPayLoad = 0; for (MobileDataWritable val : values) { upPackNum += val.getUpPackNum(); downPackNum += val.getDownPackNum(); upPayLoad += val.getUpPayLoad(); downPayLoad += val.getDownPayLoad(); } outPutKey.set(key); outPutValue.set(upPackNum, downPackNum, upPayLoad, downPayLoad); context.write(outPutKey, outPutValue); } } // run method public int run(String[] args) throws Exception { Configuration conf = super.getConf(); // create job Job job = Job.getInstance(conf, this.getClass().getSimpleName()); job.setJarByClass(this.getClass()); // set input path Path inPath = new Path(args[0]); FileInputFormat.addInputPath(job, inPath); // map job.setMapperClass(MobileDataMapper.class); job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(MobileDataWritable.class); // conbile job.setCombinerClass(MobileDataReducer.class); // reduce job.setReducerClass(MobileDataReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(MobileDataWritable.class); // output Path outPath = new Path(args[1]); FileOutputFormat.setOutputPath(job, outPath); // submit return job.waitForCompletion(true) ? 0 : 1; } public static void main(String[] args) throws Exception { args = new String[] { "hdfs://bigdata5:8020/user/nele/data/input/HTTP_20130313143750.data", "hdfs://bigdata5:8020/user/nele/data/output/output6" }; Configuration conf = new Configuration(); int status = ToolRunner.run(conf, new MobileDataMapReduce(), args); System.exit(status); } }
现在就可以使用自定义的类型进行手机流量的统计 代码如下：
/*** * MapReduce Module * * @author nele * */ public class MobileDataMapReduce extends Configured implements Tool { // map class /** * * @author nele * */ public static class MobileDataMapper extends Mapper<LongWritable, Text, Text, MobileDataWritable> { public Text outPutKey = new Text(); public MobileDataWritable outPutValue = new MobileDataWritable(); @Override public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException { System.out.println(key+":"+value); String[] arr = value.toString().split("\t"); outPutKey.set(arr[1]); outPutValue.set(Long.valueOf(arr[6]), Long.valueOf(arr[7]), Long.valueOf(arr[8]), Long.valueOf(arr[9])); context.write(outPutKey, outPutValue); } } // reduce class /*** * * @author nele * */ public static class MobileDataReducer extends Reducer<Text, MobileDataWritable, Text, MobileDataWritable> { private Text outPutKey = new Text(); private MobileDataWritable outPutValue = new MobileDataWritable(); @Override public void reduce(Text key, Iterable<MobileDataWritable> values, Context context) throws IOException, InterruptedException { long upPackNum = 0; long downPackNum = 0; long upPayLoad = 0; long downPayLoad = 0; for (MobileDataWritable val : values) { upPackNum += val.getUpPackNum(); downPackNum += val.getDownPackNum(); upPayLoad += val.getUpPayLoad(); downPayLoad += val.getDownPayLoad(); } outPutKey.set(key); outPutValue.set(upPackNum, downPackNum, upPayLoad, downPayLoad); context.write(outPutKey, outPutValue); } } // run method public int run(String[] args) throws Exception { Configuration conf = super.getConf(); // create job Job job = Job.getInstance(conf, this.getClass().getSimpleName()); job.setJarByClass(this.getClass()); // set input path Path inPath = new Path(args[0]); FileInputFormat.addInputPath(job, inPath); // map job.setMapperClass(MobileDataMapper.class); job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(MobileDataWritable.class); // conbile job.setCombinerClass(MobileDataReducer.class); // reduce job.setReducerClass(MobileDataReducer.class); job.setOutputKeyClass(Text.class); job.setOutputValueClass(MobileDataWritable.class); // output Path outPath = new Path(args[1]); FileOutputFormat.setOutputPath(job, outPath); // submit return job.waitForCompletion(true) ? 0 : 1; } public static void main(String[] args) throws Exception { args = new String[] { "hdfs://bigdata5:8020/user/nele/data/input/HTTP_20130313143750.data", "hdfs://bigdata5:8020/user/nele/data/output/output6" }; Configuration conf = new Configuration(); int status = ToolRunner.run(conf, new MobileDataMapReduce(), args); System.exit(status); } }
这样就可以统计 给出的数据日志中的手机各种流量的数据