Uses of Interface
org.apache.hadoop.io.WritableComparable

Packages that use WritableComparable
org.apache.hadoop.examples Hadoop example code. 
org.apache.hadoop.io Generic i/o code for use when reading and writing data to the network, to databases, and to files. 
org.apache.hadoop.mapred A system for scalable, fault-tolerant, distributed computation over large data collections. 
org.apache.hadoop.mapred.lib Library of generally useful mappers, reducers, and partitioners. 
org.apache.hadoop.util Common utilities. 
 

Uses of WritableComparable in org.apache.hadoop.examples
 

Methods in org.apache.hadoop.examples with parameters of type WritableComparable
 void RandomWriter.Map.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
          Given an output filename, write a bunch of random records to it.
 void WordCount.MapClass.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
           
 void PiBenchmark.PiMapper.map(WritableComparable key, Writable val, OutputCollector out, Reporter reporter)
          Map method.
 void RandomWriter.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
           
 void WordCount.Reduce.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
           
 void PiBenchmark.PiReducer.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
          Reduce method.
 

Uses of WritableComparable in org.apache.hadoop.io
 

Classes in org.apache.hadoop.io that implement WritableComparable
 class BooleanWritable
          A WritableComparable for booleans.
 class BytesWritable
          A byte sequence that is usable as a key or value.
 class FloatWritable
          A WritableComparable for floats.
 class IntWritable
          A WritableComparable for ints.
 class LongWritable
          A WritableComparable for longs.
 class MD5Hash
          A Writable for MD5 hash values.
 class UTF8
          A WritableComparable for strings that uses the UTF8 encoding.
 

Methods in org.apache.hadoop.io that return WritableComparable
 WritableComparable SetFile.Reader.get(WritableComparable key)
          Read the matching key from a set into key.
 WritableComparable WritableComparator.newKey()
          Construct a new WritableComparable instance.
 

Methods in org.apache.hadoop.io with parameters of type WritableComparable
 void SetFile.Writer.append(WritableComparable key)
          Append a key to a set.
 void MapFile.Writer.append(WritableComparable key, Writable val)
          Append a key/value pair to the map.
 int WritableComparator.compare(WritableComparable a, WritableComparable b)
          Compare two WritableComparables.
 int LongWritable.DecreasingComparator.compare(WritableComparable a, WritableComparable b)
           
 void MapFile.Reader.finalKey(WritableComparable key)
          Reads the final key from the file.
 WritableComparable SetFile.Reader.get(WritableComparable key)
          Read the matching key from a set into key.
 Writable MapFile.Reader.get(WritableComparable key, Writable val)
          Return the value for the named key, or null if none exists.
 boolean SetFile.Reader.next(WritableComparable key)
          Read the next key in a set into key.
 boolean MapFile.Reader.next(WritableComparable key, Writable val)
          Read the next key/value pair in the map into key and val.
 boolean SetFile.Reader.seek(WritableComparable key)
           
 boolean MapFile.Reader.seek(WritableComparable key)
          Positions the reader at the named key, or if none such exists, at the first entry after the named key.
 

Uses of WritableComparable in org.apache.hadoop.mapred
 

Methods in org.apache.hadoop.mapred with parameters of type WritableComparable
 void OutputCollector.collect(WritableComparable key, Writable value)
          Adds a key/value pair to the output.
static Writable MapFileOutputFormat.getEntry(MapFile.Reader[] readers, Partitioner partitioner, WritableComparable key, Writable value)
          Get an entry from output generated by this class.
 int Partitioner.getPartition(WritableComparable key, Writable value, int numPartitions)
          Returns the paritition number for a given entry given the total number of partitions.
 void Mapper.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
          Maps a single input key/value pair into intermediate key/value pairs.
 void Reducer.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
          Combines values for a given key.
 void RecordWriter.write(WritableComparable key, Writable value)
          Writes a key/value pair.
 

Uses of WritableComparable in org.apache.hadoop.mapred.lib
 

Methods in org.apache.hadoop.mapred.lib with parameters of type WritableComparable
 int HashPartitioner.getPartition(WritableComparable key, Writable value, int numReduceTasks)
          Use Object.hashCode() to partition.
 void TokenCountMapper.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
           
 void RegexMapper.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
           
 void InverseMapper.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
          The inverse function.
 void IdentityMapper.map(WritableComparable key, Writable val, OutputCollector output, Reporter reporter)
          The identify function.
 void LongSumReducer.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
           
 void IdentityReducer.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
          Writes all keys and values directly to output.
 

Uses of WritableComparable in org.apache.hadoop.util
 

Methods in org.apache.hadoop.util with parameters of type WritableComparable
 void CopyFiles.CopyFilesMapper.map(WritableComparable key, Writable val, OutputCollector out, Reporter reporter)
          Map method.
 void CopyFiles.CopyFilesReducer.reduce(WritableComparable key, Iterator values, OutputCollector output, Reporter reporter)
           
 



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