有大佬会做这个吗 急!!在集群服务器master的本地目录上有日志文件rotinstall.log,要求对文件中的单词进行统计,求单词的平均长度。
写一个java代码打包成jar包不就好了,示例代码如下
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.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.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import java.io.IOException;
public class WordCountJob extends Configured implements Tool {
public static void main(String[] args) throws Exception {
ToolRunner.run(new WordCountJob(),args);
}
@Override
public int run(String[] strings) throws Exception {
//1.创建配置累对象,设置参数
Configuration conf=new Configuration();
conf.set("fs.defaultFS","hdfs://hadoop10:9000");
//2.创建Job对象
Job job= Job.getInstance(conf);
job.setJarByClass(WordCountJob.class);
//3.设置读取文件和输出形式
job.setInputFormatClass(TextInputFormat.class);
job.setOutputFormatClass(TextOutputFormat.class);
//设置读取(必须存在)和输出(必须不存在)路径
TextInputFormat.addInputPath(job,new Path("/bai/wordcount.txt"));
TextOutputFormat.setOutputPath(job,new Path("/bai/demo"));
job.setMapperClass(WordCountMapper.class);
job.setReducerClass(WordCountReducer.class);
//4.设置程序员自定义的mapper reducer
job.setMapOutputKeyClass(Text.class);
job.setMapOutputValueClass(IntWritable.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
boolean b=job.waitForCompletion(true);//打印日志信息
//waitForCompletion等待job运行结果,如果为真代表运行成功
return b?1:0;
}
public static class WordCountMapper extends Mapper<LongWritable,Text,Text,IntWritable> {
@Override
protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
//1.key value 师Mapper输入的key-value ,分别代表偏移量和一行数据
// 2.对value进行拆分,然后对拆分的数组进行遍历
String [] names=value.toString().split(" ");
for(String name:names){
//3.使用context对象输出key-value
context.write(new Text(name),new IntWritable(1));
}
}
}
public static class WordCountReducer extends Reducer<Text,IntWritable,Text,IntWritable>{
@Override
protected void reduce(Text key, Iterable<IntWritable> values, Context context)
throws IOException, InterruptedException {
// 1.对集合遍历
// 对values集合遍历,获取里面的元素进行相加
int sum=0;
for(IntWritable v:values){
sum+=v.get();
}
//3.输出reduce计算结果,key-value
context.write(key,new IntWritable(sum));
}
}
}
如果对你有帮助,记得采纳一下哦,谢谢~
实现思路及步骤:
(1)上传otinstall.log 到HDFS目录useroov
(2)使用Hadoop官方的示例程序包
hadoop-mapreduce eamples-2 6.4.jar,以hadoop jar命令提交MapReduce任务。