大数据体系与技术实验-MapRecuce初级编程实践

大数据体系与技术

实验报告

实验题目：MapRecuce初级编程实践

一、实验目的

(1)通过实验掌握基本的MapReduce编程方法；

(2)掌握用MapReduce解决一些常见的数据处理问题，包括数据去重、数据排序和数

据挖掘等。

二、实验内容

1

社交网站上百万注册用户，网站服务器保留了用户登录

网站的日志记录，即登录一次网站，日志文件就记录一次用

户邮件地址，现有某一天的原始数据文件共800万行记录。

运营商要求定期货的用户在某天登录次数信息，作为用

户行为分析基础数据，以制定有效的运营计划。

数据清洗后提供用户名称和访问日期。

⑴编程实现按日期统计访问次数，要求获取每个自然日为

单位的所有用户访问次数。

⑵在⑴的基础上编程实现按访问次数排序。

⑶编程实现按月输出保存数据，要求最终的输出结果根据

月份分别保存到两个不同的文件中(2016年1月和2016年

2月)。同时要求输出1、2月份的记录数。

Heather,2016-02-09

Jakeem,2016~02-09

Patience,2016-02-09

Price,2016-02-09

Bell,2016-02-09

Nolan,2016-02-09

Davis,2016-02-09

Patience,2016-02-09

Patience,2016-02-09

♦・•

2.编程实现学生各科平均成绩计算。

zhangsan88

lisi99

wangwu66

zhaoliu77

zhangsan78

lisi89

wangwu96

zhaoliu67

zhangsan80

lisi82

wangwu84

zhaoliu86

实验3.统计拨打公共服务号码的电话信息

13718855152112

18610117315110

89451849112

13718855153110

13718855154112

18610117315114

18910117315114

三、实验步骤

1

社交网站上百万注册用户，网站服务器保留了用户登录

网站的日志记录，即登录一次网站，日志文件就记录一次用

户邮件地址，现有某一天的原始数据文件共800万行记录。

运营商要求定期货的用户在某天登录次数信息，作为用

户行为分析基础数据，以制定有效的运营计划。

数据清洗后提供用户名称和访问日期。

⑴编程实现按日期统计访问次数，要求获取每个自然日为

单位的所有用户访问次数。

代码如下：

packagemapreduce.util;

importjava.io.lOException;

importorg.apache.hadoop.conf.Configuration；

importorg.apache.hadoop.fs.Path；

importorg.apache.hadoop.io.IntWritable；

importorg.apache.hadoop.io.Text;

importorg.apache.hadoop.mapreduce.Job;

importorg.apache.hadoop.mapreduce.Mapper；

importorg.apache.hadoop.mapreduce.Reducer；

importorg.apache.hadoop.mapreduce.lib.input.FileinputFormat;

importorg.apache.hadoop.mapreduce.lib.output.FileOutputFormat；

importorg.apache.hadoop.util.GenericOptionsParser；

publicclassdailyAccessCount{

publicstaticclassMyMapper

extendsMapper<Object,Text,Text,IntWritable>{

privatefinalstaticIntWritableone=newIntWritable(1);

publicvoidmap(Objectkey,Textvalue,Contextcontext)

privatefinalstaticIntWritableone=newIntWritable(1);

publicvoidmap(ObjectkeyrTextvalue,Contextcontext)

throwslOException,InterruptedException{

Stringline=value.toString()；

〃指定逗号为分隔符，组成数组

Stringarray[]=line.split(",**);

//提取数组中的访问日期作为Key

StringkeyOutput=array[l];

〃组成键值对

context.write(newText(keyOutput),one)；

)

)

publicstaticclassMyReducer

extendsReducer<Text,IntWritable,Text,IntWritable>{

privateIntWritableresult=newIntWritable();

publicvoidreduce(Textkey,Iterable<IntWritable>values,Contextcontext)

publicvoidreduce(Textkey,Iterable<IntWritable>values,Contextcontext)

throwslOException,InterruptedException{

〃定义累加器，初始值为。

intsum=0;

for(IntWritableval:values){

〃将相同诞的所有值进行累加

sum+=val.get()；

}

result.set(sum)；

context.write(key,result);

)

)

publicstaticvoidmain(String[]args)throwsException{

Configurationconf=newConfiguration()；

Jobjob=Job.getlnstance(conf,"DailyAccessCount**)；

ichval*1s>r*Ruf*1auvfdai1uAruavvrciini*「lavvl•

publicstaticvoidmain(String[]args)throwsException{

Configurationconf=newConfiguration();

Jobjob=Job.getlnstance(conf,"DailyAccessCount");

job.setJarByClass(dailyAccessCount.class)；

job.setMapperClass(MyMapper.class)；

job.setReducerClass(MyReducer.class);

job.setMapOutputKeyClass(Text.class);

job.setMapOutputValueClassdntWritable.class)；

job.setOutputKeyClass(Text.class);

job.setOutputValueClass(IntWritable.class)；

for(inti=0；i<args.length-1；++i)<

FilelnputFormat.addlnputPath(job,newPath(args[i]));

)

FileOutputFormat.setOutputPathijobrnewPath(args[args.length-1]))；

System.exit(job.waitForCompletion(true)?0:1);

)

}

导出jar包

RunnableJARFileExport

RunnableJARFileSpecification

SelectaJavaApplication*launchconfigurationtousetocreatearunnableJAR.«

Launchconfiguration:

dailyAccessCount-hadoop

Exportdestination:

/usr/local/hadoop/myapp/dacjar▼Browse...

Libraryhandling:

❷ExtractrequiredlibrariesintogeneratedJAR

OPackagerequiredlibrariesintogeneratedJAR

OCopyrequiredlibrariesintoasub-foldernexttothegeneratedJAR

□SaveasANTscript

ANTscriptlocation:/home/hadoop/workspace▼Browse...

<BackNext>CancelFinish

运行jar包,

hadoop@hadoop>VtrtualBox:**$cd/usr/local/hadoop

|hadoop@hadoop-Vtrtual.Box:/usr/local/hadoop$./bin/hdfsdfs-copyFromLocal~/user/hadoop/user

_login.txt/user/root/

2022-12-3161:19:01,906INFOsasl.SaslDataTransferClient:SASLencryptiontrustcheck:local

HostTrusted=false,remoteHostTrusted=false

ihadoop@hadoop-VirtualBox:/usr/local/hadoop$./bin/hadoopjar./myapp/dac.jar/user/root/user

l_login.txt/user/root/AccessCount

2022-12-3161:21:19,950INFOimpl.MetricsConfig:loadedpropertiesfromhadoop-mp

|erties

12022-12-3161:21:20,388INFOimpl.MetricsSystemlmpl:ScheduledMetricsnapshotperiodat10

jsecond(s).

^2022-12-3101:21:20,389INFOimpl.MetricsSystemlmpl:JobTrackermetricssystemstarted

!2022-12-3161:21:22,446WARNmapreduce.JobResourceUploader:Hadoopcommand-lineoptionparst

ingnotperformed.ImplementtheToolinterfaceandexecuteyourapplicationwithToolRunner

itoremedythis.

2022-12-3161:21:23,055INFOinput.FilelnputFornat:Totalinputfilestoprocess:1

12022-12-3191:21:23,299INFOmapreduce.JobSubmitter:numberofsplits:1

2022-12-3101:21:23,727INFOmapreduce.JobSubmitter:Submittingtokensforjob:job_loca1198

,93862496061

■2022-12-3101:21:23,731INFOmapreduce.JobSubmitter:Executingwithtokens:[]

2622-12-3101:21:24,063INFOmapreduce.Job:Theurltotrackthejob:http://localhost:8080/

12022-12-3161:21:24,064INFOmapreduce.Job:Runningjob:job_locall989386249_0O01

12022-12-3161:21:24,086INFOmapred.LocalJobRunner:Outputcommittersettnconfignull

■2022-12-3161:21:24,143INFOoutput.FileOutputCommitter:FileOutputCommitterAlgorithmver

istonis2

*2022-12-3101:21:24,143INFOoutput.FileOutputCommttter:FileOutputCommitterskipcleanup_t

lemporaryfoldersunderoutputdirectory:false,ignorecleanupfailures:false

2022-12-3161:21:24,184INFOmapred.LocalJobRunner:Outputcommitterisorg.apache.hadoop.map

reduce.lib.output.FileOutputCommitter

2022-12-3161:21:24,462INFOmapred.LocalJobRunner:Waitingformaptasks

2022-12-3161:21:24,466INFOmapred.LocalJobRunner:Startingtask:attempt_local.l989386249_0

eeimeeeeeee

022-12-3101:21:23,299INFOmapreduce.JobSubmitter:numberofsplits:1

022-12-3101:21:23,727INFOnapreduce.JobSubmitter:Submittingtokensforjob:job_loca1198

•3862490001

022-12-3101:21:23,731INFOmapreduce.JobSubmttter:Executingwithtokens:[]

022-12-3101:21:24,063INFOmapreduce.Job:Theurltotrackthejob:http://localhost:8086/

022-12-3101:21:24,064INFOmapreduce.Job:Runningjob:job_locall989386249_0001

022-12-3101:21:24,086INFOmapred.LocalJobRunner:OutputCommittersettnconfignull

022-12-3101:21:24,143INFOoutput.FileOutputCommitter:FileOutputCommitterAlgorithmver

tonis2

022-12-3101:21:24,143INFOoutput.FileOutputCommitter:FileOutputCommitterskipcleanup_t

■mporaryfoldersunderoutputdtrectory:false,ignorecleanupfailures:false

022-12-3101:21:24,184INFOmapred.LocalJobRunner:OutputCommttterisorg.apache.hadoop.map

educe.lib.output.FileOutputCommitter

©22-12-3101:21:24,462INFOmapred.LocalJobRunner:Waitingformaptasks

022-12-3101:21:24,466INFOmapred.LocalJobRunner:Startingtask:attempt_locall989386249_0

i01_m_00Oe00_e

022-12-3101:21:24,583INFOoutput.FileOutputCommitter:FileOutputCommitterAlgorithmver

tonis2

022-12-3101:21:24,587INFOoutput.FileOutputCommitter:FileOutputCommitterskipcleanup_t

mporaryfoldersunderoutputdirectory:false,ignorecleanupfailures:false

022-12-3101:21:25,108INFOmapreduce.Job:Jobjob<_locall989386249_0061runninginubermod

■:false

022-12-3101:21:25,109INFOmapreduce.Job:map0%reduce0%

022-12-3101:21:25,922INFOmapred.Task:UsingResourceCalculatorProcessTree:[]

022-12-3101:21:25,943INFOmapred.MapTask:Processingsplit:hdfs://localhost:9000/user/ro

t/user_logtn.txt:0+24263613

022-12-3101:21:26,167INFOmapred.MapTask:(EQUATOR)0kvi26214396(104857584)

022-12-3101:21:26,167INFOmapred.MapTask:mapreduce.task.io.sort.mb:106

022-12-3101:21:26,167INFOmapred.MapTask:softlimitat83886080

022-12-3101:21:26,168INFOmapred.MapTask:bufstart=0;bufvoid=164857600

022-12-3101:21:26,168INFOmapred.MapTask:kvstart=26214396;length6553600

022-12-3101:21:26.191INFOmaDred.MaDTask:Maooutoutcollectorclassora.aDache.hadooD.

(82986880);length=5467677/6553600

2022-12-3101:21:31,592INFOmapred.MapTask:Finishedspill0

2022-12-3161:21:31,654INFOmapred.Task:Task:attempt_locall989386249_O001_m_0OOO6O_0isdo

|ne.Andisintheprocessofcommitting

12022-12-3161:21:31,691INFOmapred.LocalJobRunner:map

2022-12-3161:21:31,691INFOmapred.Task:Task'attempt_locaI1989386249_0OOl>_m_OO00O0_6*don

e.

2022-12-3101:21:31,759INFOmapred.Task:FinalCountersforattempt_locall989386249_e001_m_

00O0Oe_0:Counters:22

FileSystemCounters

FILE:Numberofbytesread=62941358

FILE:Numberofbyteswritten=87174082

FILE:Numberofreadoperations=0

FILE:Numberoflargereadoperations=0

FILE:Numberofwriteoperations=0

HDFS:Numberofbytesread=24263613

HDFS:Numberofbyteswritten=0

HDFS:Numberofreadoperattons=5

HDFS：Numberoflargereadoperations=0

HDFS：Numberofwriteoperations=l

Map-ReduceFramework

Mapinputrecords=1366920

Mapoutputrecords=1366920

Mapoutputbytes=2050386O

Mapoutputmaterializedbytes=23237646

Inputsplitbytes=lll

Combineinputrecords=0

SpilledRecords=1366920

FailedShuffles=6

MergedMapoutputs=0

GCtimeelapsed(ms)=172

HDFS:Numberofreadoperations=10

HDFS:Numberoflargereadoperations=0

HDFS:Numberofwriteoperattons=3

Map-ReduceFramework

Combineinputrecords=6

Combineoutputrecords=0

Reduceinputgroups=366

Reduceshufflebytes=23237646

Reduceinputrecords=1366920

Reduceoutputrecords=366

SpilledRecords=1366920

ShuffledMaps=1

FailedShuffles：。

MergedMapoutputs=l

GCtimeelapsed(ms)=3

Totalcommittedheapusage(bytes)=161746944

ShuffleErrors

BAD_ID=0

CONNECTION=O

IO_ERROR=0

WR0NG_LENGTH=0

WRONG_MAP=0

WRONG二REDUCE=。

FileOutputFormatCounters

BytesWrttten=5856

2022-12-3101:21:37,167INFOmapred.LocalJobRunner:Finishingtask:attempt_locall989386249

OOGIr0000000

2022-12-3101:21:37,212INFOmapred.LocalJobRunner:reducetaskexecutorcomplete.

2022-12-3101:21:38,132INFOmapreduce.Job:Jobjob_locall989386249__0001completedsuccessfi

iiy

2022-12-3101:21:38,185INFOmapreduce.Job:Counters:35

FileSystemCounters

FILE:Numberofbvtesread=172358040

HDFS:Numberofreadoperations=15

HDFS:Numberoflargereadoperattons=0

HDFS:Numberofwriteoperattons=4

Map-ReduceFramework

Mapinputrecords=1366920

Mapoutputrecords=1366926

Mapoutputbytes=2050380O

Mapoutputmaterializedbytes=23237646

Inputsplitbytes=lll

Combineinputrecords=0

Combineoutputrecords=6

Reduceinputgroups=366

Reduceshufflebytes=23237646

Reduceinputrecords=1366920

Reduceoutputrecords=366

SpilledRecords=2733840

ShuffledMaps=1

FailedShuffles=0

MergedMapoutputs=l

CCtimeelapsed(ms)=175

Totalcommittedheapusage(bytes)=323493888

ShuffleErrors

BAD_ID=0

CONNECTION=O

IO_ERROR=0

WRONG_LENGTH=O

WR0NG_MAP=6

WRONG~REDUCE=0

FileInputFormatCounters

BytesRead=24263613

FileOutputFormatCounters

BytesWritten=5856

输出结果如下,

hadoop@hadoop-VirtualBox:/usr/local/hadoop$./btn/hdfsdfs-cat/user/root/AccessCount/part-

r-06000

2022-12-3101:32:45,267INFOsasl.SaslDataTransferClient:SASLencryptiontrustcheck:local

HostTrusted=false,remoteHostTrusted=false

2016-01-015038

2016-01-025378

2016-01-035341

2016-61-645304

2016-01-055258

2016-01-065136

2016-61-075300

2016-01-685281

2016-61-095367

2016-01-105282

2016-01-113126

2016-61-123237

2016-01-133129

2016-01-143091

2016-01-153131

2016-61-163168

A.-17OA

j2O16-01-173124

2016-01-183065

2016-01-193135

2016-01-203154

12016-01-213078

2016-01-223234

2016-01-233131

2016-01-243179

12016-01-253152

|2016-01-263124

；2016-©1-273096

•2016-01-283121

12016-01-293698

12016-01-303094

2016-01-313885

12016-02-013077

2016-02-023018

2016-02-033184

2016-02-043217

•2016-02-053102

12016-02-063018

2016-02-673691

S2O16-02-08312©

12016-02-093154

,2016-02-163157

12016-02-113104

12016-02-123106

2016-62-133050

■2016-02-143233

!2016-02-153090

|2。16-。2-163865

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；2016-02-173158

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2016-02-193083

2016-02-203131

2016-62-213125

2016-02-223024

2016-62-233109

2016-62-243693

2016-62-253162

12016-62-263160

|2016-©2-273182

[2316-62-283140

2016-62-293201

12016-63-013062

12016-63-023206

2016-63-633115

2016-03-043170

!2016-63-653128

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2016-03-973056

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(2016-03-093119

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{2016-63-193269

2016-03-193209

2016-03-203128

2016-03-213263

2016-03-223187

2016-63-233110

2016-63-243133

2016-63-253102

2016-63-263053

2016-03-273116

2016-03-283174

2016-63-293159

2016-63-303091

2016-63-313641

2016-04-012998

2016-04-023122

2016-64-633142

2016-64-043109

2016-04-053173

2016-04-663651

2016-04-673104

2016-04-083171

2016-04-093172

2016-04-103223

2016-64-112991

2016-64-123088

2016-04-133123

2016-04-143010

2016-04-153135

2016-04-163106

2016-04-173641

2016-64-183156

2016-04-193219

12816-84-2。__3695

12016-64-203095

2016-04-213019

2016-64-223084

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2016-04-243183

2016-04-253169

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2016-04-273075

2016-04-283170

'2016-04-293127

2016-04-303091

2016-05-013105

2016-05-023136

2016-65-033105

12016-05-043103

||2016-05-053010

2016-65-063167

2016-05-673171

2016-05-083162

2016-05-093090

,2016-65-103117

peie-es-ii3176

2016-05-123202

2016-65-133064

：2O16-05-143096

2016-65-153191

2016-65-163125

12016-05-173103

12016-65-183191

2016-05-193148

2016-05-203094

'2016-65-213170

12016-65-223079

12016-05-223679

2016-05-233617

2016-65-243116

,2016-05-253190

■2016-05-263117

2616-05-273242

(2016-Q5-283127

2016-65-293277

2016-05-303117

<2016-65-313187

12016-66-013189

2016-06-023110

■2016-06-033165

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12016-06-053159

2016-06-063197

2016-66-073031

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2016-66-163158

2616-86-113135

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2016-06-273098

2016-06-283078

2016-06-293122

2016-06-303108

2016-07-015485

2016-07-025185

2016-07-035366

2016-07-045327

2016-07-055329

2016-07-065372

2016-07-675352

2016-07-685182

2016-67-695334

2016-07-105213

2016-07-115360

2016-07-123139

2016-07-133116

2016-07-143159

2016-67-153122

2016-67-163263

2016-07-173098

2016-07-183164

2016-07-193082

2016-07-203211

2016-07-213095

(2016-07-233189

|2616-07-243221

2016-07-253162

2616-07-263139

2016-07-273132

12616-07-283128

2016-07-293164

2016-07-303164

2616-07-313166

2016-08-013094

2016-08-023064

,2016-08-633148

|2016-08-043149

2016-08-053164

|2616-08-063103

2016-08-073106

2016-08-683193

2616-08-093147

2016-08-163159

2016-08-113151

2016-68-123177

2016-08-133191

2016-08-143070

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|2016-09-075317

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2016-09-105205

2016-09-115250

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2016-11-127611

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2016-11-303155

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2016-12-167259

2016-12-177475

■2016-12-187468

2016-12-197354

2016-12-207478

)2016-12-217644

2016-12-228014

[2616-12-233132

(2016-12-243078

(2016-12-253181

2016-12-263636

*2016-12-273148

12016-12-283123

,2016-12-293091__

]2616-12-25

:2016-12-263036

f2016-12-273148

52016-12-283123

12016-12-293091

；2016-12-303095

’2616-12-313106

|hadoop@hadoop-VirtualBox:/usr/local/hadoop$|

⑵在⑴的基础上编程实现按访问次数排序。

代码如下，

packagemapreduce.util;

importjava.io.lOException;

importorg.apache.hadoop.conf.Configuration；

importorg.apache.hadoop.fs.Path；

importorg.apache.hadoop.io.IntWritable;

importorg.apache.hadoop.io.Text;

importorg.apache.hadoop.mapreduce.Job；

importorg.apache.hadoop.mapreduce.Mapper；

importorg.apache.hadoop.mapreduce.Reducer；

importorg.apache.hadoop.mapreduce.lib.input.FilelnputFormat;

importorg.apache.hadoop.mapreduce.lib.output.FileOutputFormat；

importorg.apache.hadoop.util.GenericOptionsParser；

publicclassaccessTimesSort{

publicstaticclassMyMapper

extendsMapper<Object,Text,IntWritable,Text>{

publicvoidmanfnhiortkav一Tpxt\/alUQ-Ccntpxtccntaxt

publicstaticclassMyMapper

extendsMapper<Object,Text,IntWritable,Text>{

publicvoidmap(Objectkey.Textvalue.Contextcontext

)throwslOException,InterruptedException{

Stringlines=value.tostring()；

//指定tab为分隔符，组成数组

Stringarray[]=lines.split("\t");

〃提取访问次数做为Key

intkeyOutput=Integer.parselnt(array[l]);

〃提取访问日期做为Values

StringvalueOutput-array[0]；

context.write(newIntWritable(keyOutput),newText(valueoutput)

)

)

publicstaticclassMyReducer

extendsReducer<IntWritable,Text,Text,IntWritable>{

publicstaticclassMyReducer

extendsReducer<IntWritable,Text,Text,IntWritablo{

publicvoidreduce(IntWritablekey,Iterable<Text>values,

Contextcontext)

throwslOException,InterruptedException{

for(Textvalue:values){

context.writetvalue,key);

)

publicstati