Package org.esa.snap.core.util

Class CollectionHelper

java.lang.Object

org.esa.snap.core.util.CollectionHelper

public final class CollectionHelper
extends Object

Helper class for simplifying lambda expression usage on collections and arrays.

Constructor Summary

Constructors

Constructor	Description
CollectionHelper()

Method Summary

Modifier and Type	Method	Description
static <T> T	firstOrDefault(Collection<T> collection, Predicate<T> condition)	Returns the first element of the collection that satisfies the given condition, or null if no such element exists.
static <T> T	firstOrDefault(T[] array, Predicate<T> condition)	Returns the first element of the array that satisfies the given condition, or null if no such element exists.
static <T> List<T>	where(Collection<T> collection, Predicate<T> filter)	Selects the list of collection elements that satisfy the given filter.
static <T> List<T>	where(T[] array, Predicate<T> filter)	Selects the list of array elements that satisfy the given filter.

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionHelper

public CollectionHelper()

Method Detail

firstOrDefault

public static <T> T firstOrDefault(Collection<T> collection,
                                   Predicate<T> condition)

Returns the first element of the collection that satisfies the given condition, or null if no such element exists. If the condition is null, the first element of the collection is returned.

Type Parameters:

T - The type of the collection elements

Parameters:

collection - The collection to be searched

condition - The condition to be applied

Returns:

The first element of the collection matching the condition, or null

firstOrDefault

public static <T> T firstOrDefault(T[] array,
                                   Predicate<T> condition)

Returns the first element of the array that satisfies the given condition, or null if no such element exists. If the condition is null, the first element of the array is returned.

Type Parameters:

T - The type of the array elements

Parameters:

array - The array to be searched

condition - The condition to be applied

Returns:

The first element of the array matching the condition, or null

where

public static <T> List<T> where(Collection<T> collection,
                                Predicate<T> filter)

Selects the list of collection elements that satisfy the given filter. If the filter is null, all the collection elements are returned.

Type Parameters:

T - The type of collection elements

Parameters:

collection - The collection to be filtered

filter - The filter to be applied

Returns:

A list of elements satisfying the filter

where

public static <T> List<T> where(T[] array,
                                Predicate<T> filter)

Selects the list of array elements that satisfy the given filter. If the filter is null, all the array elements are returned.

Type Parameters:

T - The type of array elements

Parameters:

array - The array to be filtered

filter - The filter to be applied

Returns:

A list of elements satisfying the filter