com.helger.commons.aggregate

Interface IAggregator<SRCTYPE,DSTTYPE>

Type Parameters:

SRCTYPE - The input type.

DSTTYPE - The output type.

All Superinterfaces:

Function<Collection<SRCTYPE>,DSTTYPE>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface IAggregator<SRCTYPE,DSTTYPE>
extends Function<Collection<SRCTYPE>,DSTTYPE>

Aggregate a list of input objects to an output object.

Author:

Philip Helger

Method Summary

Modifier and Type	Method and Description
default DSTTYPE	apply(SRCTYPE... aObjects) Aggregate a collection of input objects to a single output object.
static <SRCTYPE,DSTTYPE> IAggregator<SRCTYPE,DSTTYPE>	createConstant(DSTTYPE aValue)
static <SRCTYPE,DSTTYPE> IAggregator<SRCTYPE,DSTTYPE>	createNull()
static IAggregator<String,String>	createStringAll()
static IAggregator<String,String>	createStringAll(char cSep)
static IAggregator<String,String>	createStringAll(String sSep)
static IAggregator<String,String>	createStringIgnoreEmpty()
static IAggregator<String,String>	createStringIgnoreEmpty(char cSep)
static IAggregator<String,String>	createStringIgnoreEmpty(String sSep)
static <SRCTYPE> IAggregator<SRCTYPE,Collection<SRCTYPE>>	createUseAll()
static <SRCTYPE> IAggregator<SRCTYPE,SRCTYPE>	createUseFirst()
static <SRCTYPE> IAggregator<SRCTYPE,SRCTYPE>	createUseLast()

Methods inherited from interface java.util.function.Function

andThen, apply, compose, identity

Method Detail

apply

@Nullable
default DSTTYPE apply(@Nonnull
                                 SRCTYPE... aObjects)

Aggregate a collection of input objects to a single output object.

Parameters:

aObjects - Source objects. May not be null.

Returns:

The aggregated object. May be null.

createNull

@Nonnull
static <SRCTYPE,DSTTYPE> IAggregator<SRCTYPE,DSTTYPE> createNull()

createConstant

@Nonnull
static <SRCTYPE,DSTTYPE> IAggregator<SRCTYPE,DSTTYPE> createConstant(@Nullable
                                                                               DSTTYPE aValue)

createUseAll

@Nonnull
static <SRCTYPE> IAggregator<SRCTYPE,Collection<SRCTYPE>> createUseAll()

createUseFirst

@Nonnull
static <SRCTYPE> IAggregator<SRCTYPE,SRCTYPE> createUseFirst()

createUseLast

@Nonnull
static <SRCTYPE> IAggregator<SRCTYPE,SRCTYPE> createUseLast()

createStringAll

@Nonnull
static IAggregator<String,String> createStringAll()

createStringAll

@Nonnull
static IAggregator<String,String> createStringAll(char cSep)

createStringAll

@Nonnull
static IAggregator<String,String> createStringAll(@Nonnull
                                                            String sSep)

createStringIgnoreEmpty

@Nonnull
static IAggregator<String,String> createStringIgnoreEmpty()

createStringIgnoreEmpty

@Nonnull
static IAggregator<String,String> createStringIgnoreEmpty(char cSep)

createStringIgnoreEmpty

@Nonnull
static IAggregator<String,String> createStringIgnoreEmpty(@Nonnull
                                                                    String sSep)