hadoop实训实验报告代码.rar

package cn.sky.hadoop; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.conf.Configured; import org.apache.hadoop.fs.Path; import org.apache.hadoop.io.LongWritable; import org.apache.hadoop.io.Text; import org.apache.hadoop.mapreduce.Job; import org.apache.hadoop.mapreduce.lib.input.TextInputFormat; import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat; import org.apache.hadoop.util.Tool; import org.apache.hadoop.util.ToolRunner; import org.junit.Test; public class JobMain extends Configured implements Tool { @Override public int run(String[] strings) throws Exception { // 创建一个任务对象 Job job = Job.getInstance(super.getConf(), "mapreduce_temperature"); // 打包放在集群运行时，需要做一个配置 job.setJarByClass(JobMain.class); // 第一步：设置读取文件的类：K1和V1 job.setInputFormatClass(TextInputFormat.class); TextInputFormat.addInputPath(job, new Path("hdfs://node01:8020/usr/hadoop/in")); // 第二步：设置Mapper类 job.setMapperClass(TemperatureMapper.class); // 设置Map阶段的输出类型：k2和v2的类型 job.setMapOutputKeyClass(Text.class); job.setMapOutputValueClass(LongWritable.class); // 第三、四、五、六步采用默认方式（分区，排序，规约，分组） // 第七步：设置Reducer类 job.setReducerClass(TemperatureReducer.class); // 设置Reduce阶段的输出类型 job.setOutputKeyClass(Text.class); job.setOutputValueClass(Temperature.class); // 第八步：设置输出类 job.setOutputFormatClass(TextOutputFormat.class); // 设置输出路径 TextOutputFormat.setOutputPath(job, new Path("hdfs://node01:8020/usr/hadoop/temperature")); boolean b = job.waitForCompletion(true); return b?0:1; } public static void main(String[] args) throws Exception { Configuration configuration = new Configuration(); // 启动一个任务 ToolRunner.run(configuration, new JobMain(), args); } }