小编Nip*_*ock的帖子

"键入地图中的键不匹配:期望org.apache.hadoop.io.IntWritable,收到org.apache.hadoop.io.LongWritable" - 每件事看起来都是正确的

我正在尝试编写简单的map reduce程序,以使用新的API(0.20.2)找到最大的素数.这就是我的Map和reduce类的样子......

public class PrimeNumberMap extends Mapper<LongWritable, Text, IntWritable, IntWritable> {

public void map (LongWritable key, Text Kvalue,Context context) throws IOException,InterruptedException
{
    Integer value = new Integer(Kvalue.toString());
    if(isNumberPrime(value))
    {
            context.write(new IntWritable(value), new IntWritable(new Integer(key.toString())));
    }
}

boolean isNumberPrime(Integer number)
{
    if (number == 1) return false;
     if (number == 2) return true;

     for (int counter =2; counter<(number/2);counter++)
     {
         if(number%counter ==0 )
             return false;
     }
            return true;

}
}
public class PrimeNumberReduce extends Reducer<IntWritable, IntWritable, IntWritable, IntWritable>  {

public void reduce …
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