hu.akarnokd.reactive4java.reactive

Class GroupBy<Key,U,T>

java.lang.Object

hu.akarnokd.reactive4java.reactive.GroupBy<Key,U,T>

Type Parameters:

Key - the group key type

U - the output element type

T - the source element type

All Implemented Interfaces:

Observable<GroupedObservable<Key,U>>

public class GroupBy<Key,U,T>
extends java.lang.Object
implements Observable<GroupedObservable<Key,U>>

Group the specified source according to the keys provided by the extractor function and compute key equality by the comparer function. The resulting observable gets notified once a new group is encountered. Each previously encountered group by itself receives updates along the way. If the source finish(), all encountered group will finish().

Exception semantics: if the source sends an exception, the group observable and the individual groups' observables receive this error.

Since:

0.97

Field Summary

Fields

Modifier and Type	Field and Description
protected Func2<? super Key,? super Key,java.lang.Boolean>	keyComparer

Constructor Summary

Constructors

Constructor and Description
GroupBy(Observable<? extends T> source, Func1<? super T,? extends Key> keyExtractor, Func2<? super Key,? super Key,java.lang.Boolean> keyComparer, Func1<? super T,? extends U> valueExtractor) Constructor.

Method Summary

Modifier and Type	Method and Description
java.io.Closeable	register(Observer<? super GroupedObservable<Key,U>> observer) Registers an observer for the notification of Ts.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

keyComparer

protected final Func2<? super Key,? super Key,java.lang.Boolean> keyComparer

Constructor Detail

GroupBy

public GroupBy(Observable<? extends T> source,
               Func1<? super T,? extends Key> keyExtractor,
               Func2<? super Key,? super Key,java.lang.Boolean> keyComparer,
               Func1<? super T,? extends U> valueExtractor)

Constructor.

Parameters:

source - the source sequence

keyExtractor - the key extractor

keyComparer - the key comparator

valueExtractor - the value extractor

Method Detail

register

@Nonnull
public java.io.Closeable register(@Nonnull
                                            Observer<? super GroupedObservable<Key,U>> observer)

Description copied from interface: Observable

Registers an observer for the notification of Ts.

Specified by:

register in interface Observable<GroupedObservable<Key,U>>

Parameters:

observer - the observer of Ts or any supertype of it

Returns:

the way of deregister the observer from this provider