但我打包成jar檔後，在ubuntu的終端機使用指令hadoop jar來執行卻會有錯誤...就是使用者輸入的值會沒有傳回到Hadoop，造成Hadoop會使用預設值0來計算。
package wordcount;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import java.util.StringTokenizer;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
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.input.KeyValueTextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;
import org.apache.hadoop.util.Progressable;
import java.util.Scanner;
public class WordCount {
static String[] Path = new String[2];
static int count = 0;
static int a, b;
public static class TokenizerMapper extends Mapper<Text, Text, Text, Text>{
public void map(Text key, Text value, Context context)
throws IOException, InterruptedException {
String[] values = value.toString().split(",");
String result = new String();
double x = Double.valueOf(values[0]);
double y = Double.valueOf(values[1]);
double sum1 = x + y;
double z = y*a;
result = sum1 +","+ z;
context.write(key, new Text(result));
}
}
public static class IntSumReducer extends Reducer<Text,Text,Text,Text> {
public void reduce(Text key, Iterable<Text> values, Context context)
throws IOException, InterruptedException {
for (Text val : values) {
String[] revalues = val.toString().split(",");
String f_result = new String();
double m = Double.valueOf(revalues[0]);
double n = Double.valueOf(revalues[1]);
double sum2 = m + n*2;
double o = m*b;
f_result = sum2 + "," + o;
context.write(key, new Text(f_result));
}
}
}
public static void main(String[] args) throws Exception {
/*System.out.println("Hi");
for(int i=2; i<args.length; i++){
System.out.println(args[i]);
}
a = Integer.valueOf(args[2]);
b = Integer.valueOf(args[3]);*/
Scanner scanner = new Scanner(System.in);//System.in用來取得使用者的輸入
System.out.println("please input a number for a");
a = scanner.nextInt();// 將數字取出
System.out.println("please input a number for b");
b = scanner.nextInt();// 將數字取出
System.out.println("a: " + a + " b: " + b);
Configuration conf = new Configuration();
String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
/*
if (otherArgs.length != 2) {
System.err.println("Usage: wordcount <in> <out>");
System.exit(2);
}
*/
Job job = new Job(conf, "word count");
job.setJarByClass(WordCount.class);
job.setMapperClass(TokenizerMapper.class);
job.setReducerClass(IntSumReducer.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(Text.class);
job.setInputFormatClass(KeyValueTextInputFormat.class);
FileInputFormat.addInputPath(job, new Path(otherArgs[0]));
FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));
System.exit(job.waitForCompletion(true) ? 0 : 1);
}
}
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