如何在hadoop中使用JobControl
我想把两个文件合并成一个。 我做了两个绘图器来阅读,一个减速器来连接如何在hadoop中使用JobControl,hadoop,Hadoop,我想把两个文件合并成一个。 我做了两个绘图器来阅读,一个减速器来连接 JobConf classifiedConf = new JobConf(new Configuration()); classifiedConf.setJarByClass(myjob.class); classifiedConf.setJobName("classifiedjob"); FileInputFormat.setInputPaths(classifiedC
JobConf classifiedConf = new JobConf(new Configuration());
classifiedConf.setJarByClass(myjob.class);
classifiedConf.setJobName("classifiedjob");
FileInputFormat.setInputPaths(classifiedConf,classifiedInputPath );
classifiedConf.setMapperClass(ClassifiedMapper.class);
classifiedConf.setMapOutputKeyClass(TextPair.class);
classifiedConf.setMapOutputValueClass(Text.class);
Job classifiedJob = new Job(classifiedConf);
//first mapper config
JobConf featureConf = new JobConf(new Configuration());
featureConf.setJobName("featureJob");
featureConf.setJarByClass(myjob.class);
FileInputFormat.setInputPaths(featureConf, featuresInputPath);
featureConf.setMapperClass(FeatureMapper.class);
featureConf.setMapOutputKeyClass(TextPair.class);
featureConf.setMapOutputValueClass(Text.class);
Job featureJob = new Job(featureConf);
//second mapper config
JobConf joinConf = new JobConf(new Configuration());
joinConf.setJobName("joinJob");
joinConf.setJarByClass(myjob.class);
joinConf.setReducerClass(JoinReducer.class);
joinConf.setOutputKeyClass(Text.class);
joinConf.setOutputValueClass(Text.class);
Job joinJob = new Job(joinConf);
//reducer config
//JobControl config
joinJob.addDependingJob(featureJob);
joinJob.addDependingJob(classifiedJob);
secondJob.addDependingJob(joinJob);
JobControl jobControl = new JobControl("jobControl");
jobControl.addJob(classifiedJob);
jobControl.addJob(featureJob);
jobControl.addJob(secondJob);
Thread thread = new Thread(jobControl);
thread.start();
while(jobControl.allFinished()){
jobControl.stop();
}
但是,我得到了这个信息:
WARN mapred.JobClient:
Use GenericOptionsParser for parsing the arguments. Applications should implement Tool for the same.
WARN mapred.JobClient: No job jar file set. User classes may not be found. See JobConf(Class) or JobConf#setJar(String).
任何人都可以帮助您…………您使用的是哪个版本的Hadoop 您收到的警告将停止程序 您不需要使用setJarByClass()。您可以看到我的代码段,我可以不使用setJarByClass()方法运行它
您应该以以下方式执行您的工作:
public class MyApp extends Configured implements Tool {
public int run(String[] args) throws Exception {
// Configuration processed by ToolRunner
Configuration conf = getConf();
// Create a JobConf using the processed conf
JobConf job = new JobConf(conf, MyApp.class);
// Process custom command-line options
Path in = new Path(args[1]);
Path out = new Path(args[2]);
// Specify various job-specific parameters
job.setJobName("my-app");
job.setInputPath(in);
job.setOutputPath(out);
job.setMapperClass(MyMapper.class);
job.setReducerClass(MyReducer.class);
// Submit the job, then poll for progress until the job is complete
JobClient.runJob(job);
return 0;
}
public static void main(String[] args) throws Exception {
// Let ToolRunner handle generic command-line options
int res = ToolRunner.run(new Configuration(), new MyApp(), args);
System.exit(res);
}
}
这直接来自Hadoop的文档
因此,基本上您的作业需要继承自
配置的
并实现工具
。这将迫使您实现run()
。然后使用Toolrunner.run(,)
从主类启动作业,警告将消失。您需要在驱动程序job.setJarByClass(MapperClassName.class)中包含此代码;
public class MyApp extends Configured implements Tool {
public int run(String[] args) throws Exception {
// Configuration processed by ToolRunner
Configuration conf = getConf();
// Create a JobConf using the processed conf
JobConf job = new JobConf(conf, MyApp.class);
// Process custom command-line options
Path in = new Path(args[1]);
Path out = new Path(args[2]);
// Specify various job-specific parameters
job.setJobName("my-app");
job.setInputPath(in);
job.setOutputPath(out);
job.setMapperClass(MyMapper.class);
job.setReducerClass(MyReducer.class);
// Submit the job, then poll for progress until the job is complete
JobClient.runJob(job);
return 0;
}
public static void main(String[] args) throws Exception {
// Let ToolRunner handle generic command-line options
int res = ToolRunner.run(new Configuration(), new MyApp(), args);
System.exit(res);
}
}