org.apache.hadoop.mapreduce.lib.join

クラス TupleWritable

java.lang.Object

org.apache.hadoop.mapreduce.lib.join.TupleWritable

すべての実装されたインタフェース:

Iterable<Writable>, Writable

直系の既知のサブクラス:

TupleWritable

@InterfaceAudience.Public
 @InterfaceStability.Stable
public class TupleWritable
extends Object
implements Writable, Iterable<Writable>

Writable type storing multiple Writables. This is *not* a general-purpose tuple type. In almost all cases, users are encouraged to implement their own serializable types, which can perform better validation and provide more efficient encodings than this class is capable. TupleWritable relies on the join framework for type safety and assumes its instances will rarely be persisted, assumptions not only incompatible with, but contrary to the general case.

関連項目:

Writable

フィールドのサマリー

フィールド

修飾子とタイプ	フィールドと説明
protected BitSet	written

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
TupleWritable() Create an empty tuple with no allocated storage for writables.
TupleWritable(Writable[] vals) Initialize tuple with storage; unknown whether any of them contain "written" values.

メソッドのサマリー

修飾子とタイプ	メソッドと説明
boolean	equals(Object other)
Writable	get(int i) Get ith Writable from Tuple.
boolean	has(int i) Return true if tuple has an element at the position provided.
int	hashCode()
Iterator<Writable>	iterator() Return an iterator over the elements in this tuple.
void	readFields(DataInput in) Deserialize the fields of this object from in.
int	size() The number of children in this Tuple.
String	toString() Convert Tuple to String as in the following.
void	write(DataOutput out) Writes each Writable to out.

クラスから継承されたメソッド java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

インタフェースから継承されたメソッド java.lang.Iterable

forEach, spliterator

フィールドの詳細

written

protected BitSet written

コンストラクタの詳細

TupleWritable

public TupleWritable()

Create an empty tuple with no allocated storage for writables.

TupleWritable

public TupleWritable(Writable[] vals)

Initialize tuple with storage; unknown whether any of them contain "written" values.

メソッドの詳細

has

public boolean has(int i)

Return true if tuple has an element at the position provided.

get

public Writable get(int i)

Get ith Writable from Tuple.

size

public int size()

The number of children in this Tuple.

equals

public boolean equals(Object other)

オーバーライド:

equals クラス内 Object

hashCode

public int hashCode()

オーバーライド:

hashCode クラス内 Object

iterator

public Iterator<Writable> iterator()

Return an iterator over the elements in this tuple. Note that this doesn't flatten the tuple; one may receive tuples from this iterator.

定義:

iterator インタフェース内 Iterable<Writable>

toString

public String toString()

Convert Tuple to String as in the following. [<child1>,<child2>,...,<childn>]

オーバーライド:

toString クラス内 Object

write

public void write(DataOutput out)
           throws IOException

Writes each Writable to out. TupleWritable format: <count><type1><type2>...<typen><obj1><obj2>...<objn>

定義:

write インタフェース内 Writable

パラメータ:

out - DataOuput to serialize this object into.

例外:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

定義:

readFields インタフェース内 Writable

パラメータ:

in - DataInput to deseriablize this object from.

例外:

IOException