hadoop记录topk

lk@lk-virtual-machine:~$ cd hadoop-1.0.1

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin dfs -mkdir input

bash: ./bin: 是一个文件夹

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop  dfs -mkdir input

14/05/11 21:12:07 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 0 time(s).

14/05/11 21:12:08 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 1 time(s).

14/05/11 21:12:09 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 2 time(s).

14/05/11 21:12:10 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 3 time(s).

14/05/11 21:12:11 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 4 time(s).

14/05/11 21:12:12 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 5 time(s).

14/05/11 21:12:13 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 6 time(s).

14/05/11 21:12:14 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 7 time(s).

14/05/11 21:12:15 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 8 time(s).

14/05/11 21:12:16 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:9000. Already tried 9 time(s).

Bad connection to FS. command aborted. exception: Call to localhost/127.0.0.1:9000 failed on connection exception: java.net.ConnectException: Connection refused

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop namenode -format

14/05/11 21:12:48 INFO namenode.NameNode: STARTUP_MSG:

/************************************************************

STARTUP_MSG: Starting NameNode

STARTUP_MSG:   host = lk-virtual-machine/127.0.1.1

STARTUP_MSG:   args = [-format]

STARTUP_MSG:   version = 1.0.1

STARTUP_MSG:   build = https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r 1243785; compiled by 'hortonfo' on Tue Feb 14 08:15:38 UTC 2012

************************************************************/

14/05/11 21:12:48 INFO util.GSet: VM type       = 32-bit

14/05/11 21:12:48 INFO util.GSet: 2% max memory = 19.33375 MB

14/05/11 21:12:48 INFO util.GSet: capacity      = 2^22 = 4194304 entries

14/05/11 21:12:48 INFO util.GSet: recommended=4194304, actual=4194304

14/05/11 21:12:50 INFO namenode.FSNamesystem: fsOwner=lk

14/05/11 21:12:50 INFO namenode.FSNamesystem: supergroup=supergroup

14/05/11 21:12:50 INFO namenode.FSNamesystem: isPermissionEnabled=true

14/05/11 21:12:50 INFO namenode.FSNamesystem: dfs.block.invalidate.limit=100

14/05/11 21:12:50 INFO namenode.FSNamesystem: isAccessTokenEnabled=false accessKeyUpdateInterval=0 min(s), accessTokenLifetime=0 min(s)

14/05/11 21:12:50 INFO namenode.NameNode: Caching file names occuring more than 10 times

14/05/11 21:12:50 INFO common.Storage: Image file of size 108 saved in 0 seconds.

14/05/11 21:12:50 INFO common.Storage: Storage directory /tmp/hadoop-lk/dfs/name has been successfully formatted.

14/05/11 21:12:50 INFO namenode.NameNode: SHUTDOWN_MSG:

/************************************************************

SHUTDOWN_MSG: Shutting down NameNode at lk-virtual-machine/127.0.1.1

************************************************************/

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop namenode -format

14/05/11 21:13:12 INFO namenode.NameNode: STARTUP_MSG:

/************************************************************

STARTUP_MSG: Starting NameNode

STARTUP_MSG:   host = lk-virtual-machine/127.0.1.1

STARTUP_MSG:   args = [-format]

STARTUP_MSG:   version = 1.0.1

STARTUP_MSG:   build = https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.0 -r 1243785; compiled by 'hortonfo' on Tue Feb 14 08:15:38 UTC 2012

************************************************************/

Re-format filesystem in /tmp/hadoop-lk/dfs/name ? (Y or N) n

Format aborted in /tmp/hadoop-lk/dfs/name

14/05/11 21:13:21 INFO namenode.NameNode: SHUTDOWN_MSG:

/************************************************************

SHUTDOWN_MSG: Shutting down NameNode at lk-virtual-machine/127.0.1.1

************************************************************/

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/start-all.sh

starting namenode, logging to /home/lk/hadoop-1.0.1/libexec/../logs/hadoop-lk-namenode-lk-virtual-machine.out

localhost: starting datanode, logging to /home/lk/hadoop-1.0.1/libexec/../logs/hadoop-lk-datanode-lk-virtual-machine.out

localhost: starting secondarynamenode, logging to /home/lk/hadoop-1.0.1/libexec/../logs/hadoop-lk-secondarynamenode-lk-virtual-machine.out

starting jobtracker, logging to /home/lk/hadoop-1.0.1/libexec/../logs/hadoop-lk-jobtracker-lk-virtual-machine.out

localhost: starting tasktracker, logging to /home/lk/hadoop-1.0.1/libexec/../logs/hadoop-lk-tasktracker-lk-virtual-machine.out

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop dfs -mkdir input

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop dfs -put ~/input/file* input

lk@lk-virtual-machine:~/hadoop-1.0.1$ javac -classpath hadoop-core-1.0.1.jar:lib/commons-cli-1.2.jar -d WordCount WordCount.java

javac: 找不到文件： WordCount.java

使用方法: javac <options> <source files>

-help 用于列出可能的选项

lk@lk-virtual-machine:~/hadoop-1.0.1$ javac -classpath hadoop-core-1.0.1.jar:lib/commons-cli-1.2.jar -d WordCount ~/WordCount.java

lk@lk-virtual-machine:~/hadoop-1.0.1$ jar -cvf wordcount.jar -C WordCount .

标明清单(manifest)

添加：wordcount/(读入= 0) (写出= 0)(存储了 0%)

添加：wordcount/WordCount$Map.class(读入= 1765) (写出= 771)(压缩了 56%)

添加：wordcount/WordCount.class(读入= 1808) (写出= 963)(压缩了 46%)

添加：wordcount/WordCount$Reduce.class(读入= 1741) (写出= 738)(压缩了 57%)

lk@lk-virtual-machine:~/hadoop-1.0.1$ ./bin/hadoop jar wordcount.jar wordcount input output

Exception in thread "main" java.lang.ClassNotFoundException: wordcount

    at java.net.URLClassLoader$1.run(URLClassLoader.java:217)

    at java.security.AccessController.doPrivileged(Native Method)

    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)

    at java.lang.Class.forName0(Native Method)

    at java.lang.Class.forName(Class.java:266)

    at org.apache.hadoop.util.RunJar.main(RunJar.java:149)

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$

lk@lk-virtual-machine:~/hadoop-1.0.1$ jps

2598 SecondaryNameNode

2341 DataNode

2693 JobTracker

2950 TaskTracker

3247 Jps

2061 NameNode

lk@lk-virtual-machine:~/hadoop-1.0.1$ cd bin

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/Runer.jar wordcount input output

Exception in thread "main" java.lang.ClassNotFoundException: wordcount

    at java.net.URLClassLoader$1.run(URLClassLoader.java:217)

    at java.security.AccessController.doPrivileged(Native Method)

    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)

    at java.lang.Class.forName0(Native Method)

    at java.lang.Class.forName(Class.java:266)

    at org.apache.hadoop.util.RunJar.main(RunJar.java:149)

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/Runer.jar WordCount input output

Exception in thread "main" java.lang.NoClassDefFoundError: WordCount (wrong name: org/apache/hadoop/examples/WordCount)

    at java.lang.ClassLoader.defineClass1(Native Method)

    at java.lang.ClassLoader.defineClass(ClassLoader.java:634)

    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)

    at java.net.URLClassLoader.defineClass(URLClassLoader.java:277)

    at java.net.URLClassLoader.access$000(URLClassLoader.java:73)

    at java.net.URLClassLoader$1.run(URLClassLoader.java:212)

    at java.security.AccessController.doPrivileged(Native Method)

    at java.net.URLClassLoader.findClass(URLClassLoader.java:205)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:321)

    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:314)

    at java.lang.ClassLoader.loadClass(ClassLoader.java:266)

    at java.lang.Class.forName0(Native Method)

    at java.lang.Class.forName(Class.java:266)

    at org.apache.hadoop.util.RunJar.main(RunJar.java:149)

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/Run.jar wordcount.WordCount  input output

Exception in thread "main" java.net.UnknownHostException: unknown host: master01

    at org.apache.hadoop.ipc.Client$Connection.<init>(Client.java:214)

    at org.apache.hadoop.ipc.Client.getConnection(Client.java:1192)

    at org.apache.hadoop.ipc.Client.call(Client.java:1046)

    at org.apache.hadoop.ipc.RPC$Invoker.invoke(RPC.java:225)

    at sun.proxy.$Proxy1.getProtocolVersion(Unknown Source)

    at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:396)

    at org.apache.hadoop.ipc.RPC.getProxy(RPC.java:379)

    at org.apache.hadoop.hdfs.DFSClient.createRPCNamenode(DFSClient.java:119)

    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:238)

    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:203)

    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:89)

    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:1386)

    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:66)

    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:1404)

    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:254)

    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:187)

    at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.addInputPath(FileInputFormat.java:372)

    at wordcount.WordCount.main(WordCount.java:61)

    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

    at java.lang.reflect.Method.invoke(Method.java:616)

    at org.apache.hadoop.util.RunJar.main(RunJar.java:156)

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/Ru.jar wordcount.WordCount  input output

14/05/11 22:43:50 WARN mapred.JobClient: Use GenericOptionsParser for parsing the arguments. Applications should implement Tool for the same.

****hdfs://localhost:9000/user/lk/input

14/05/11 22:43:52 INFO input.FileInputFormat: Total input paths to process : 4

14/05/11 22:43:56 INFO mapred.JobClient: Running job: job_201405112114_0001

14/05/11 22:43:57 INFO mapred.JobClient:  map 0% reduce 0%

14/05/11 22:45:45 INFO mapred.JobClient:  map 50% reduce 0%

14/05/11 22:46:59 INFO mapred.JobClient:  map 100% reduce 0%

14/05/11 22:47:02 INFO mapred.JobClient:  map 100% reduce 16%

14/05/11 22:47:05 INFO mapred.JobClient:  map 100% reduce 100%

14/05/11 22:47:33 INFO mapred.JobClient: Job complete: job_201405112114_0001

14/05/11 22:47:34 INFO mapred.JobClient: Counters: 29

14/05/11 22:47:34 INFO mapred.JobClient:   Job Counters

14/05/11 22:47:34 INFO mapred.JobClient:     Launched reduce tasks=1

14/05/11 22:47:34 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=321173

14/05/11 22:47:34 INFO mapred.JobClient:     Total time spent by all reduces waiting after reserving slots (ms)=0

14/05/11 22:47:34 INFO mapred.JobClient:     Total time spent by all maps waiting after reserving slots (ms)=0

14/05/11 22:47:34 INFO mapred.JobClient:     Launched map tasks=4

14/05/11 22:47:34 INFO mapred.JobClient:     Data-local map tasks=2

14/05/11 22:47:34 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=84371

14/05/11 22:47:34 INFO mapred.JobClient:   File Output Format Counters

14/05/11 22:47:34 INFO mapred.JobClient:     Bytes Written=41

14/05/11 22:47:34 INFO mapred.JobClient:   FileSystemCounters

14/05/11 22:47:34 INFO mapred.JobClient:     FILE_BYTES_READ=104

14/05/11 22:47:34 INFO mapred.JobClient:     HDFS_BYTES_READ=480

14/05/11 22:47:34 INFO mapred.JobClient:     FILE_BYTES_WRITTEN=106420

14/05/11 22:47:34 INFO mapred.JobClient:     HDFS_BYTES_WRITTEN=41

14/05/11 22:47:34 INFO mapred.JobClient:   File Input Format Counters

14/05/11 22:47:34 INFO mapred.JobClient:     Bytes Read=50

14/05/11 22:47:34 INFO mapred.JobClient:   Map-Reduce Framework

14/05/11 22:47:34 INFO mapred.JobClient:     Map output materialized bytes=122

14/05/11 22:47:34 INFO mapred.JobClient:     Map input records=2

14/05/11 22:47:34 INFO mapred.JobClient:     Reduce shuffle bytes=122

14/05/11 22:47:34 INFO mapred.JobClient:     Spilled Records=16

14/05/11 22:47:34 INFO mapred.JobClient:     Map output bytes=82

14/05/11 22:47:34 INFO mapred.JobClient:     CPU time spent (ms)=20800

14/05/11 22:47:34 INFO mapred.JobClient:     Total committed heap usage (bytes)=718479360

14/05/11 22:47:34 INFO mapred.JobClient:     Combine input records=0

14/05/11 22:47:34 INFO mapred.JobClient:     SPLIT_RAW_BYTES=430

14/05/11 22:47:34 INFO mapred.JobClient:     Reduce input records=8

14/05/11 22:47:34 INFO mapred.JobClient:     Reduce input groups=5

14/05/11 22:47:34 INFO mapred.JobClient:     Combine output records=0

14/05/11 22:47:34 INFO mapred.JobClient:     Physical memory (bytes) snapshot=550727680

14/05/11 22:47:34 INFO mapred.JobClient:     Reduce output records=5

14/05/11 22:47:34 INFO mapred.JobClient:     Virtual memory (bytes) snapshot=1881079808

14/05/11 22:47:34 INFO mapred.JobClient:     Map output records=8

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop dfs -ls output

Found 3 items

-rw-r--r--   1 lk supergroup          0 2014-05-11 22:47 /user/lk/output/_SUCCESS

drwxr-xr-x   - lk supergroup          0 2014-05-11 22:43 /user/lk/output/_logs

-rw-r--r--   1 lk supergroup         41 2014-05-11 22:47 /user/lk/output/part-r-00000

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop dfs -cat output/part-r-00000

Bye    1

Goodbye    1

Hadoop    2

Hello    2

World    2

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/topk.jar topk.TopK  input output

14/05/11 23:00:26 INFO mapred.JobClient: Cleaning up the staging area hdfs://localhost:9000/tmp/hadoop-lk/mapred/staging/lk/.staging/job_201405112114_0002

14/05/11 23:00:26 ERROR security.UserGroupInformation: PriviledgedActionException as:lk cause:org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory output already exists

Exception in thread "main" org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory output already exists

    at org.apache.hadoop.mapreduce.lib.output.FileOutputFormat.checkOutputSpecs(FileOutputFormat.java:137)

    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:889)

    at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:850)

    at java.security.AccessController.doPrivileged(Native Method)

    at javax.security.auth.Subject.doAs(Subject.java:416)

    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)

    at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:850)

    at org.apache.hadoop.mapreduce.Job.submit(Job.java:500)

    at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:530)

    at topk.TopK.run(TopK.java:86)

    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)

    at topk.TopK.main(TopK.java:90)

    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)

    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

    at java.lang.reflect.Method.invoke(Method.java:616)

    at org.apache.hadoop.util.RunJar.main(RunJar.java:156)

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop dfs -rmr output

Deleted hdfs://localhost:9000/user/lk/output

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$ ./hadoop jar ~/hadoop-1.0.1/topk.jar topk.TopK  input output

****hdfs://localhost:9000/user/lk/input

14/05/11 23:01:28 INFO input.FileInputFormat: Total input paths to process : 4

14/05/11 23:01:29 INFO mapred.JobClient: Running job: job_201405112114_0003

14/05/11 23:01:30 INFO mapred.JobClient:  map 0% reduce 0%

14/05/11 23:02:32 INFO mapred.JobClient:  map 50% reduce 0%

14/05/11 23:02:34 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000000_0, Status : FAILED

java.lang.ArrayIndexOutOfBoundsException: 8

    at topk.TopK$MapClass.map(TopK.java:43)

    at topk.TopK$MapClass.map(TopK.java:1)

    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)

    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)

    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)

    at org.apache.hadoop.mapred.Child$4.run(Child.java:255)

    at java.security.AccessController.doPrivileged(Native Method)

    at javax.security.auth.Subject.doAs(Subject.java:416)

    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)

    at org.apache.hadoop.mapred.Child.main(Child.java:249)



14/05/11 23:02:36 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000001_0, Status : FAILED

java.lang.ArrayIndexOutOfBoundsException: 8

    at topk.TopK$MapClass.map(TopK.java:43)

    at topk.TopK$MapClass.map(TopK.java:1)

    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)

    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)

    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)

    at org.apache.hadoop.mapred.Child$4.run(Child.java:255)

    at java.security.AccessController.doPrivileged(Native Method)

    at javax.security.auth.Subject.doAs(Subject.java:416)

    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)

    at org.apache.hadoop.mapred.Child.main(Child.java:249)



14/05/11 23:02:39 INFO mapred.JobClient:  map 0% reduce 0%

14/05/11 23:03:02 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000000_1, Status : FAILED

14/05/11 23:03:02 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000001_1, Status : FAILED

14/05/11 23:03:27 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000000_2, Status : FAILED

java.lang.ArrayIndexOutOfBoundsException: 8

    at topk.TopK$MapClass.map(TopK.java:43)

    at topk.TopK$MapClass.map(TopK.java:1)

    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)

    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)

    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)

    at org.apache.hadoop.mapred.Child$4.run(Child.java:255)

    at java.security.AccessController.doPrivileged(Native Method)

    at javax.security.auth.Subject.doAs(Subject.java:416)

    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)

    at org.apache.hadoop.mapred.Child.main(Child.java:249)



14/05/11 23:03:29 INFO mapred.JobClient: Task Id : attempt_201405112114_0003_m_000001_2, Status : FAILED

java.lang.ArrayIndexOutOfBoundsException: 8

    at topk.TopK$MapClass.map(TopK.java:43)

    at topk.TopK$MapClass.map(TopK.java:1)

    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:144)

    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:764)

    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:370)

    at org.apache.hadoop.mapred.Child$4.run(Child.java:255)

    at java.security.AccessController.doPrivileged(Native Method)

    at javax.security.auth.Subject.doAs(Subject.java:416)

    at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1093)

    at org.apache.hadoop.mapred.Child.main(Child.java:249)



14/05/11 23:03:59 INFO mapred.JobClient: Job complete: job_201405112114_0003

14/05/11 23:04:00 INFO mapred.JobClient: Counters: 7

14/05/11 23:04:00 INFO mapred.JobClient:   Job Counters

14/05/11 23:04:00 INFO mapred.JobClient:     SLOTS_MILLIS_MAPS=255192

14/05/11 23:04:00 INFO mapred.JobClient:     Total time spent by all reduces waiting after reserving slots (ms)=0

14/05/11 23:04:00 INFO mapred.JobClient:     Total time spent by all maps waiting after reserving slots (ms)=0

14/05/11 23:04:00 INFO mapred.JobClient:     Launched map tasks=8

14/05/11 23:04:00 INFO mapred.JobClient:     Data-local map tasks=8

14/05/11 23:04:00 INFO mapred.JobClient:     SLOTS_MILLIS_REDUCES=0

14/05/11 23:04:00 INFO mapred.JobClient:     Failed map tasks=1

lk@lk-virtual-machine:~/hadoop-1.0.1/bin$

package topk;

/**
 * Created with IntelliJ IDEA.
 * User: Isaac Li
 * Date: 12/4/12
 * Time: 5:48 PM
 * To change this template use File | Settings | File Templates.
 */

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
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.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

import java.io.IOException;
import java.util.TreeMap;

//鍒╃敤MapReduce姹傛渶澶у€兼捣閲忔暟鎹腑鐨凨涓暟
public class TopK extends Configured implements Tool {

    public static class MapClass extends Mapper<LongWritable, Text, NullWritable, Text> {
        public static final int K = 1;
        private TreeMap<Integer, Text> fatcats = new TreeMap<Integer, Text>();
        public void map(LongWritable key, Text value, Context context)
                throws IOException, InterruptedException {

            String[] str = value.toString().split(",", -2);
            int temp = Integer.parseInt(str[8]);
            fatcats.put(temp, value);
            if (fatcats.size() > K)
                fatcats.remove(fatcats.firstKey());
        }
        @Override
        protected void cleanup(Context context) throws IOException,  InterruptedException {
            for(Text text: fatcats.values()){
                context.write(NullWritable.get(), text);
            }
        }
    }

    public static class Reduce extends Reducer<NullWritable, Text, NullWritable, Text> {
        public static final int K = 1;
        private TreeMap<Integer, Text> fatcats = new TreeMap<Integer, Text>();
        public void reduce(NullWritable key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            for (Text val : values) {
                String v[] = val.toString().split("\t");
                Integer weight = Integer.parseInt(v[1]);
                fatcats.put(weight, val);
                if (fatcats.size() > K)
                    fatcats.remove(fatcats.firstKey());
            }
            for (Text text: fatcats.values())
                context.write(NullWritable.get(), text);
        }
    }

    public int run(String[] args) throws Exception {
        Configuration conf = getConf();
        Job job = new Job(conf, "TopK");
        job.setJarByClass(TopK.class);
        FileInputFormat.setInputPaths(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));
        job.setMapperClass(MapClass.class);
       // job.setCombinerClass(Reduce.class);
        job.setReducerClass(Reduce.class);
        job.setInputFormatClass(TextInputFormat.class);
        job.setOutputFormatClass(TextOutputFormat.class);
        job.setOutputKeyClass(NullWritable.class);
        job.setOutputValueClass(Text.class);
        System.exit(job.waitForCompletion(true) ? 0 : 1);
        return 0;
    }
    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(new Configuration(), new TopK(), args);
        System.exit(res);
    }

}