hadoop在eclipse当中如何添加源码?

[学习笔记]

/*org.apache.hadoop.mapreduce.Mapper.Context,java.lang.InterruptedException,想看map的源代码,按control,点击,出现Attach Source Code,点击External Location/External File,找到源代码,就在Source目录下,,D:\hadoop-2.7.4\src
 其中key为此行的开头相对于文件的起始位置,value就是此行的字符文本
  */  public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
            System.out.println("key is 马克-to-win @ 马克java社区 "+key.toString()+" value is "+value.toString());
            StringTokenizer itr = new StringTokenizer(value.toString());
            while (itr.hasMoreTokens()) {
                word.set(itr.nextToken());
                context.write(word, one);
            }
        }
    }

    public static class IntSumReducer extends Reducer<Text, IntWritable, Text, IntWritable> {
        private IntWritable result = new IntWritable();
        public void reduce(Text key, Iterable<IntWritable> values, Context context)
                throws IOException, InterruptedException {
            System.out.println("reduce key is 马克-to-win @ 马克java社区 "+key.toString());
            int sum = 0;
            for (IntWritable val : values) {
                int valValue=val.get();
                System.out.println("valValue is"+valValue);
                sum += valValue ;
            }
            result.set(sum);
            context.write(key, result);
        }
    }


    public static void main(String[] args) throws Exception {
        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);

更多内容请见原文,文章转载自原文:https://blog.csdn.net/qq_44594249/article/details/96110661

posted @ 2019-09-02 09:45  海中一神兽  阅读(238)  评论(0编辑  收藏  举报