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

Packages that use Writable
org.apache.hadoop.dfs A distributed implementation of FileSystem
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.ipc Tools to help define network clients and servers. 
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.tools   
org.apache.hadoop.util Common utilities. 
 

Uses of Writable in org.apache.hadoop.dfs
 

Classes in org.apache.hadoop.dfs that implement Writable
 class DatanodeID
          DatanodeID is composed of the data node name (hostname:portNumber) and the data storage ID, which it currently represents.
 class DatanodeInfo
          DatanodeInfo represents the status of a DataNode.
 class DataNodeReport
          Deprecated. Use DatanodeInfo instead.
 

Uses of Writable in org.apache.hadoop.examples
 

Methods in org.apache.hadoop.examples with parameters of type Writable
 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 NNBench.Map.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
          Given a number of files to create, create and open those files.
 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.
 

Uses of Writable in org.apache.hadoop.io
 

Subinterfaces of Writable in org.apache.hadoop.io
 interface WritableComparable
          An interface which extends both Writable and Comparable.
 

Classes in org.apache.hadoop.io that implement Writable
 class ArrayWritable
          A Writable for arrays containing instances of a class.
 class BooleanWritable
          A WritableComparable for booleans.
 class BytesWritable
          A byte sequence that is usable as a key or value.
 class CompressedWritable
          A base-class for Writables which store themselves compressed and lazily inflate on field access.
 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 NullWritable
          Singleton Writable with no data.
 class ObjectWritable
          A polymorphic Writable that writes an instance with it's class name.
 class Text
          This class stores text using standard UTF8 encoding.
 class TwoDArrayWritable
          A Writable for 2D arrays containing a matrix of instances of a class.
 class UTF8
          Deprecated. replaced by Text
 class VersionedWritable
          A base class for Writables that provides version checking.
 

Methods in org.apache.hadoop.io that return Writable
static Writable WritableUtils.clone(Writable orig, JobConf conf)
          Make a copy of a writable object using serialization to a buffer.
 Writable[][] TwoDArrayWritable.get()
           
 Writable[] ArrayWritable.get()
           
 Writable ArrayFile.Reader.get(long n, Writable value)
          Return the nth value in the file.
 Writable MapFile.Reader.get(WritableComparable key, Writable val)
          Return the value for the named key, or null if none exists.
 Writable WritableFactory.newInstance()
          Return a new instance.
static Writable WritableFactories.newInstance(Class c)
          Create a new instance of a class with a defined factory.
static Writable WritableFactories.newInstance(Class c, Configuration conf)
          Create a new instance of a class with a defined factory.
 Writable ArrayFile.Reader.next(Writable value)
          Read and return the next value in the file.
 

Methods in org.apache.hadoop.io with parameters of type Writable
 void ArrayFile.Writer.append(Writable value)
          Append a value to the file.
 void MapFile.Writer.append(WritableComparable key, Writable val)
          Append a key/value pair to the map.
 void SequenceFile.Writer.append(Writable key, Writable val)
          Append a key/value pair.
static Writable WritableUtils.clone(Writable orig, JobConf conf)
          Make a copy of a writable object using serialization to a buffer.
 Writable ArrayFile.Reader.get(long n, Writable value)
          Return the nth value in the file.
 Writable MapFile.Reader.get(WritableComparable key, Writable val)
          Return the value for the named key, or null if none exists.
 void SequenceFile.Reader.getCurrentValue(Writable val)
          Get the 'value' corresponding to the last read 'key'.
 boolean SequenceFile.Reader.next(Writable key)
          Read the next key in the file into key, skipping its value.
 Writable ArrayFile.Reader.next(Writable value)
          Read and return the next value in the file.
 boolean MapFile.Reader.next(WritableComparable key, Writable val)
          Read the next key/value pair in the map into key and val.
 boolean SequenceFile.Reader.next(Writable key, Writable val)
          Read the next key/value pair in the file into key and val.
 void ArrayWritable.set(Writable[] values)
           
 void TwoDArrayWritable.set(Writable[][] values)
           
 

Constructors in org.apache.hadoop.io with parameters of type Writable
ArrayWritable(Class valueClass, Writable[] values)
           
TwoDArrayWritable(Class valueClass, Writable[][] values)
           
 

Uses of Writable in org.apache.hadoop.ipc
 

Methods in org.apache.hadoop.ipc that return Writable
 Writable RPC.Server.call(Writable param)
           
abstract  Writable Server.call(Writable param)
          Called for each call.
 Writable[] Client.call(Writable[] params, InetSocketAddress[] addresses)
          Makes a set of calls in parallel.
 Writable Client.call(Writable param, InetSocketAddress address)
          Make a call, passing param, to the IPC server running at address, returning the value.
 

Methods in org.apache.hadoop.ipc with parameters of type Writable
 Writable RPC.Server.call(Writable param)
           
abstract  Writable Server.call(Writable param)
          Called for each call.
 Writable[] Client.call(Writable[] params, InetSocketAddress[] addresses)
          Makes a set of calls in parallel.
 Writable Client.call(Writable param, InetSocketAddress address)
          Make a call, passing param, to the IPC server running at address, returning the value.
 

Uses of Writable in org.apache.hadoop.mapred
 

Classes in org.apache.hadoop.mapred that implement Writable
 class ClusterStatus
          Summarizes the size and current state of the cluster.
 class FileSplit
          A section of an input file.
 class JobStatus
          Describes the current status of a job.
 class TaskReport
          A report on the state of a task.
 

Methods in org.apache.hadoop.mapred that return Writable
 Writable TextInputFormat.LineRecordReader.createValue()
           
 Writable SequenceFileRecordReader.createValue()
           
 Writable RecordReader.createValue()
          Create an object of the appropriate type to be used as the value.
static Writable MapFileOutputFormat.getEntry(MapFile.Reader[] readers, Partitioner partitioner, WritableComparable key, Writable value)
          Get an entry from output generated by this class.
 

Methods in org.apache.hadoop.mapred with parameters of type Writable
 boolean SequenceFileInputFilter.Filter.accept(Writable key)
          filter function Decide if a record should be filtered or not
 boolean SequenceFileInputFilter.RegexFilter.accept(Writable key)
          Filtering method If key matches the regex, return true; otherwise return false
 boolean SequenceFileInputFilter.PercentFilter.accept(Writable key)
          Filtering method If record# % frequency==0, return true; otherwise return false
 boolean SequenceFileInputFilter.MD5Filter.accept(Writable key)
          Filtering method If MD5(key) % frequency==0, return true; otherwise return false
 void OutputCollector.collect(WritableComparable key, Writable value)
          Adds a key/value pair to the output.
protected  void SequenceFileRecordReader.getCurrentValue(Writable value)
           
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.
protected  boolean SequenceFileRecordReader.next(Writable key)
           
 boolean TextInputFormat.LineRecordReader.next(Writable key, Writable value)
          Read a line.
 boolean SequenceFileRecordReader.next(Writable key, Writable value)
           
 boolean RecordReader.next(Writable key, Writable value)
          Reads the next key/value pair.
 void TextOutputFormat.LineRecordWriter.write(WritableComparable key, Writable value)
           
 void RecordWriter.write(WritableComparable key, Writable value)
          Writes a key/value pair.
 

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

Methods in org.apache.hadoop.mapred.lib with parameters of type Writable
 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.
 

Uses of Writable in org.apache.hadoop.tools
 

Methods in org.apache.hadoop.tools with parameters of type Writable
 void Logalyzer.LogRegexMapper.map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
           
 

Uses of Writable in org.apache.hadoop.util
 

Methods in org.apache.hadoop.util with parameters of type Writable
 void CopyFiles.DFSCopyFilesMapper.map(WritableComparable key, Writable value, OutputCollector out, Reporter reporter)
          Map method.
 void CopyFiles.HTTPCopyFilesMapper.map(WritableComparable key, Writable val, OutputCollector out, Reporter reporter)
           
 



Copyright © 2006 The Apache Software Foundation