类 org.apache.hadoop.io.LongWritable
的使用

使用LongWritable的程序包

程序包	说明
org.apache.hadoop.examples	Hadoop example code.
org.apache.hadoop.examples.terasort	This package consists of 3 map/reduce applications for Hadoop to compete in the annual terabyte sort competition.
org.apache.hadoop.mapred	A software framework for easily writing applications which process vast amounts of data (multi-terabyte data-sets) parallelly on large clusters (thousands of nodes) built of commodity hardware in a reliable, fault-tolerant manner.
org.apache.hadoop.mapred.lib	Library of generally useful mappers, reducers, and partitioners.
org.apache.hadoop.mapred.lib.db	org.apache.hadoop.mapred.lib.db Package This package contains a library to read records from a database as an input to a mapreduce job, and write the output records to the database.
org.apache.hadoop.mapreduce.lib.db
org.apache.hadoop.mapreduce.lib.input
org.apache.hadoop.mapreduce.lib.reduce
org.apache.hadoop.tools
org.apache.hadoop.typedbytes	Typed bytes are sequences of bytes in which the first byte is a type code.

org.apache.hadoop.examples中LongWritable的使用

参数类型为LongWritable的org.apache.hadoop.examples中的方法

限定符和类型	方法和说明
void	PiEstimator.PiMapper.map(LongWritable offset, LongWritable size, OutputCollector<BooleanWritable,LongWritable> out, Reporter reporter) Map method.
void	SecondarySort.MapClass.map(LongWritable inKey, Text inValue, Mapper.Context context)

类型变量类型为LongWritable的org.apache.hadoop.examples中的方法参数

限定符和类型	方法和说明
void	PiEstimator.PiMapper.map(LongWritable offset, LongWritable size, OutputCollector<BooleanWritable,LongWritable> out, Reporter reporter) Map method.
void	MultiFileWordCount.MapClass.map(MultiFileWordCount.WordOffset key, Text value, OutputCollector<Text,LongWritable> output, Reporter reporter)
void	PiEstimator.PiReducer.reduce(BooleanWritable isInside, Iterator<LongWritable> values, OutputCollector<WritableComparable<?>,Writable> output, Reporter reporter) Accumulate number of points inside/outside results from the mappers.

org.apache.hadoop.examples.terasort中LongWritable的使用

参数类型为LongWritable的org.apache.hadoop.examples.terasort中的方法

限定符和类型	方法和说明
void	TeraGen.SortGenMapper.map(LongWritable row, NullWritable ignored, OutputCollector<Text,Text> output, Reporter reporter)

org.apache.hadoop.mapred中LongWritable的使用

返回LongWritable的org.apache.hadoop.mapred中的方法

限定符和类型	方法和说明
LongWritable	LineRecordReader.createKey()

返回变量类型为LongWritable的类型的org.apache.hadoop.mapred中的方法

限定符和类型	方法和说明
RecordReader<LongWritable,Text>	TextInputFormat.getRecordReader(InputSplit genericSplit, JobConf job, Reporter reporter)

参数类型为LongWritable的org.apache.hadoop.mapred中的方法

限定符和类型	方法和说明
boolean	LineRecordReader.next(LongWritable key, Text value) Read a line.

org.apache.hadoop.mapred.lib中LongWritable的使用

返回变量类型为LongWritable的类型的org.apache.hadoop.mapred.lib中的方法

限定符和类型	方法和说明
RecordReader<LongWritable,Text>	NLineInputFormat.getRecordReader(InputSplit genericSplit, JobConf job, Reporter reporter)

类型变量类型为LongWritable的org.apache.hadoop.mapred.lib中的方法参数

限定符和类型	方法和说明
void	TokenCountMapper.map(K key, Text value, OutputCollector<Text,LongWritable> output, Reporter reporter)
void	RegexMapper.map(K key, Text value, OutputCollector<Text,LongWritable> output, Reporter reporter)
void	LongSumReducer.reduce(K key, Iterator<LongWritable> values, OutputCollector<K,LongWritable> output, Reporter reporter)
void	LongSumReducer.reduce(K key, Iterator<LongWritable> values, OutputCollector<K,LongWritable> output, Reporter reporter)

org.apache.hadoop.mapred.lib.db中LongWritable的使用

返回LongWritable的org.apache.hadoop.mapred.lib.db中的方法

限定符和类型	方法和说明
LongWritable	DBInputFormat.DBRecordReader.createKey() Create an object of the appropriate type to be used as a key.

返回变量类型为LongWritable的类型的org.apache.hadoop.mapred.lib.db中的方法

限定符和类型	方法和说明
RecordReader<LongWritable,T>	DBInputFormat.getRecordReader(InputSplit split, JobConf job, Reporter reporter) Get the RecordReader for the given InputSplit.

参数类型为LongWritable的org.apache.hadoop.mapred.lib.db中的方法

限定符和类型	方法和说明
boolean	DBInputFormat.DBRecordReader.next(LongWritable key, T value) Reads the next key/value pair from the input for processing.

org.apache.hadoop.mapreduce.lib.db中LongWritable的使用

返回LongWritable的org.apache.hadoop.mapreduce.lib.db中的方法

限定符和类型	方法和说明
LongWritable	DBRecordReader.getCurrentKey() Get the current key

返回变量类型为LongWritable的类型的org.apache.hadoop.mapreduce.lib.db中的方法

限定符和类型	方法和说明
protected RecordReader<LongWritable,T>	OracleDataDrivenDBInputFormat.createDBRecordReader(DBInputFormat.DBInputSplit split, Configuration conf)
protected RecordReader<LongWritable,T>	DBInputFormat.createDBRecordReader(DBInputFormat.DBInputSplit split, Configuration conf)
protected RecordReader<LongWritable,T>	DataDrivenDBInputFormat.createDBRecordReader(DBInputFormat.DBInputSplit split, Configuration conf)
RecordReader<LongWritable,T>	DBInputFormat.createRecordReader(InputSplit split, TaskAttemptContext context) Create a record reader for a given split.

参数类型为LongWritable的org.apache.hadoop.mapreduce.lib.db中的方法

限定符和类型	方法和说明
boolean	DBRecordReader.next(LongWritable key, T value) 已过时。 Use DBRecordReader.nextKeyValue()

org.apache.hadoop.mapreduce.lib.input中LongWritable的使用

返回LongWritable的org.apache.hadoop.mapreduce.lib.input中的方法

限定符和类型	方法和说明
LongWritable	LineRecordReader.getCurrentKey()

返回变量类型为LongWritable的类型的org.apache.hadoop.mapreduce.lib.input中的方法

限定符和类型	方法和说明
RecordReader<LongWritable,Text>	TextInputFormat.createRecordReader(InputSplit split, TaskAttemptContext context)
RecordReader<LongWritable,Text>	NLineInputFormat.createRecordReader(InputSplit genericSplit, TaskAttemptContext context)

org.apache.hadoop.mapreduce.lib.reduce中LongWritable的使用

类型变量类型为LongWritable的org.apache.hadoop.mapreduce.lib.reduce中的方法参数

限定符和类型	方法和说明
void	LongSumReducer.reduce(KEY key, Iterable<LongWritable> values, Reducer.Context context)

org.apache.hadoop.tools中LongWritable的使用

类型变量类型为LongWritable的org.apache.hadoop.tools中的方法参数

限定符和类型	方法和说明
void	Logalyzer.LogRegexMapper.map(K key, Text value, OutputCollector<Text,LongWritable> output, Reporter reporter)

org.apache.hadoop.typedbytes中LongWritable的使用

返回LongWritable的org.apache.hadoop.typedbytes中的方法

限定符和类型	方法和说明
LongWritable	TypedBytesWritableInput.readLong()
LongWritable	TypedBytesWritableInput.readLong(LongWritable lw)

参数类型为LongWritable的org.apache.hadoop.typedbytes中的方法

限定符和类型	方法和说明
LongWritable	TypedBytesWritableInput.readLong(LongWritable lw)
void	TypedBytesWritableOutput.writeLong(LongWritable lw)