接口 org.apache.hadoop.mapred.join.ComposableRecordReader
的使用

使用ComposableRecordReader的程序包

程序包	说明
org.apache.hadoop.mapred.join	Given a set of sorted datasets keyed with the same class and yielding equal partitions, it is possible to effect a join of those datasets prior to the map.

org.apache.hadoop.mapred.join中ComposableRecordReader的使用

实现ComposableRecordReader的org.apache.hadoop.mapred.join中的类

限定符和类型	类和说明
class	InnerJoinRecordReader<K extends WritableComparable> Full inner join.
class	JoinRecordReader<K extends WritableComparable> Base class for Composite joins returning Tuples of arbitrary Writables.
class	MultiFilterRecordReader<K extends WritableComparable,V extends Writable> Base class for Composite join returning values derived from multiple sources, but generally not tuples.
class	OuterJoinRecordReader<K extends WritableComparable> Full outer join.
class	OverrideRecordReader<K extends WritableComparable,V extends Writable> Prefer the "rightmost" data source for this key.
class	WrappedRecordReader<K extends WritableComparable,U extends Writable> Proxy class for a RecordReader participating in the join framework.

声明为ComposableRecordReader的org.apache.hadoop.mapred.join中的字段

限定符和类型	字段和说明
protected ComposableRecordReader<K,? extends V>[]	CompositeRecordReader.kids

类型参数类型为ComposableRecordReader的org.apache.hadoop.mapred.join中的字段

限定符和类型	字段和说明
protected static Map<String,Constructor<? extends ComposableRecordReader>>	Parser.Node.rrCstrMap

返回ComposableRecordReader的org.apache.hadoop.mapred.join中的方法

限定符和类型	方法和说明
ComposableRecordReader<K,TupleWritable>	CompositeInputFormat.getRecordReader(InputSplit split, JobConf job, Reporter reporter) Construct a CompositeRecordReader for the children of this InputFormat as defined in the init expression.
ComposableRecordReader<K,V>	ComposableInputFormat.getRecordReader(InputSplit split, JobConf job, Reporter reporter)

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

限定符和类型	方法和说明
protected PriorityQueue<ComposableRecordReader<K,?>>	CompositeRecordReader.getRecordReaderQueue() Return sorted list of RecordReaders for this composite.

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

限定符和类型	方法和说明
void	CompositeRecordReader.add(ComposableRecordReader<K,? extends V> rr) Add a RecordReader to this collection.
int	WrappedRecordReader.compareTo(ComposableRecordReader<K,?> other) Implement Comparable contract (compare key at head of proxied RR with that of another).
int	CompositeRecordReader.compareTo(ComposableRecordReader<K,?> other) Implement Comparable contract (compare key of join or head of heap with that of another).

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

限定符和类型	方法和说明
protected static void	Parser.Node.addIdentifier(String ident, Class<?>[] mcstrSig, Class<? extends Parser.Node> nodetype, Class<? extends ComposableRecordReader> cl) For a given identifier, add a mapping to the nodetype for the parse tree and to the ComposableRecordReader to be created, including the formals required to invoke the constructor.