为什么我无法运行 hadoop jar 文件，每次我运行它时都会说它说类未找到异常 itemclick.itemclic

Question

我使用了下面的代码，并使用以下命令运行了hadoopjar文件hadoop jar '/home/manthanjain/Hadoop-click-analysis/Itemclick.jar' itemclick.itemclick.ItemClick '/Hadoop-click-analysis/Input' '/Hadoop-click-analysis/Output'这里的输入和输出文件是加载在Hadoop中的hdfs文件

package itemclick.itemclick;
import java.io.IOException;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
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.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;
public class ItemClick {
public static class ItemClickMapper extends Mapper<Object, Text, Text, IntWritable>{
public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
Text itemID = new Text();
IntWritable one = new IntWritable(1);
String[] tokens = value.toString().split(",");
String[] timestamp = tokens[1].split("-");
if(timestamp[1].equals("04")) {
itemID.set(tokens[2]);
context.write(itemID, one);
}
}
}
public static class SumReducer extends Reducer<Text, IntWritable, Text, IntWritable>{
public void reduce(Text itemID, Iterable<IntWritable> ones, Context context) throws IOException, InterruptedException {
int count = 0;
Iterator<IntWritable> iterator = ones.iterator();
while(iterator.hasNext()) {
count++;
iterator.next();
}
IntWritable clicks = new IntWritable(count);
context.write(itemID, clicks);
}
}
public static class ItemClickMapper2 extends Mapper<Object, Text, IntWritable, Text>{
public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
String[] tokens = value.toString().split("t");
Text itemId = new Text(tokens[0]);
int clicks = Integer.parseInt(tokens[1]);
IntWritable clicksFinal = new IntWritable(clicks);
context.write(clicksFinal, itemId);
}
}
public static class SumReducer2 extends Reducer<IntWritable, Text, Text, IntWritable>{
private Map<String, Integer> countMap = new HashMap<String, Integer>();
@Override
public void reduce(IntWritable key, Iterable<Text> values, Context context) throws IOException, InterruptedException {
for (Text value: values) {
countMap.put(value.toString(), key.get());
}
}
public void cleanup(Context context) throws IOException, InterruptedException {
Map<String, Integer> sortedMap = sort(countMap);
int counter = 0;
for (String key: sortedMap.keySet()) {
if (counter ++ == 10) {
break;
}
context.write(new Text(key),new IntWritable(sortedMap.get(key)));
}
}
public static Map<String, Integer> sort(Map<String, Integer> unsortMap) {
List<Map.Entry<String, Integer>> list =
new LinkedList<Map.Entry<String, Integer>>(unsortMap.entrySet());
//          for (Map.Entry<String, Integer> entry : list) {
//              System.out.println("-----IN COMPARATOR METHOD------"+entry.getKey()+"  "+entry.getValue());
//          }
Collections.sort(list, new Comparator<Map.Entry<String, Integer>>() {
public int compare(Map.Entry<String, Integer> o1,
Map.Entry<String, Integer> o2) {
if(!o2.getValue().equals(o1.getValue()))
return (o2.getValue()).compareTo(o1.getValue());
else
return (o1.getKey().compareTo(o2.getKey()));
}
});
Map<String, Integer> sortedMap = new LinkedHashMap<String, Integer>();
for (Map.Entry<String, Integer> entry : list) {
sortedMap.put(entry.getKey(), entry.getValue());
}
return sortedMap;
}
//context.write(itemId, key);
}

public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
Configuration conf1 = new Configuration();
String[] otherArgs = new GenericOptionsParser(conf1, args).getRemainingArgs();
if (otherArgs.length !=2) {
System.err.println("Usage: input_file output_file");
System.exit(2);
}
Job job1 = Job.getInstance(conf1, "Item Click");
job1.setJarByClass(ItemClick.class);
job1.setMapperClass(ItemClickMapper.class);
job1.setReducerClass(SumReducer.class);
job1.setNumReduceTasks(10);
job1.setOutputKeyClass(Text.class);
job1.setMapOutputValueClass(IntWritable.class);
FileInputFormat.addInputPath(job1, new Path(otherArgs[0]));
FileOutputFormat.setOutputPath(job1, new Path(otherArgs[1]+"/temp"));
if (!job1.waitForCompletion(true)) {
System.exit(1);
}
Job job2 = Job.getInstance(conf1);
job2.setJarByClass(ItemClick.class);
job2.setJobName("sort");
job2.setNumReduceTasks(1);
FileInputFormat.setInputPaths(job2, new Path(otherArgs[1] + "/temp"));
FileOutputFormat.setOutputPath(job2, new Path(otherArgs[1] + "/final"));
job2.setMapperClass(ItemClickMapper2.class);
job2.setReducerClass(SumReducer2.class);
job2.setMapOutputKeyClass(IntWritable.class);
job2.setMapOutputValueClass(Text.class);
job2.setOutputKeyClass(Text.class);
job2.setOutputValueClass(IntWritable.class);
if (!job2.waitForCompletion(true)) {
System.exit(1);
}
}
}```

Answer 1

我希望这对你有帮助

java -cp Itemclick.jar:./conf/:./lib:$HADOOP_CLASSPATH itemclick.itemclick.ItemClick  /Hadoop-click-analysis/Input  /Hadoop-click-analysis/Output