忽略hadoop減速器

Question

Iam初學者到hadoop。我決定創建一個情感分析程序。我有一個映射器類。映射器的輸出是LongWritable和Text格式。輸入到減速器。因此，我有一個減速器類

public class sentreducer extends Reducer<LongWritable,Text,LongWritable,Text>{ 
      @Override 
      public void reduce(LongWritable key,Iterable<Text>value,Context context){ 
      } 

編譯器顯示錯誤，說該方法不能被重寫。爲什麼？

Answer 1

我認爲你必須在減少方法拋出IOException的一個和InterruptedException的即

public class sentreducer extends Reducer<LongWritable,Text,LongWritable,Text>{ 
    @Override 
    public void reduce(LongWritable key,Iterable<Text> value,Context context) throws IOException, InterruptedException { 
    } 
} 

Answer 2

方法簽名應該是

public void reduce(LongWritable key, Iterator<Text> values, 
     OutputCollector<LongWritable, Text> collector, Reporter reporter) throws IOException