com.github.mjeanroy.junit.servers.commons

Class CollectionUtils

java.lang.Object

com.github.mjeanroy.junit.servers.commons.CollectionUtils

public final class CollectionUtils
extends Object

Static collection utilities.

Internal API: these methods are part of the internal API and may be removed, have their signature change, or have their access level decreased from public to protected, package, or private in future versions without notice.

Method Summary

Modifier and Type	Method and Description
static <T> List<T>	concat(List<T> inputs, T newValue) Concat new value to existing inputs and returns new outputs.
static boolean	isEmpty(Collection<?> collection) Check if a collection is null or empty.
static <T> String	join(Iterable<T> values, String separator) Join elements of a collection to a final string using a given separator.
static <T,U> List<U>	map(Collection<T> inputs, Mapper<T,U> mapper) Map input values to output values.

Methods inherited from class java.lang.Object

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

Method Detail

isEmpty

public static boolean isEmpty(Collection<?> collection)

Check if a collection is null or empty.

Parameters:

collection - Collection to check.

Returns:

True if collection is null or empty, false otherwise.

join

public static <T> String join(Iterable<T> values,
                              String separator)

Join elements of a collection to a final string using a given separator. Note that:

• If values is null, null will be returned.
• If separator is null, an empty string is used instead.

Type Parameters:

T - Type of elements in the collection.

Parameters:

values - The values to join.

separator - Value separator.

Returns:

The joined elements.

map

public static <T,U> List<U> map(Collection<T> inputs,
                                Mapper<T,U> mapper)

Map input values to output values.

Type Parameters:

T - Type of input values.

U - Type of output values.

Parameters:

inputs - Input values.

mapper - Mapper function.

Returns:

Output values.

concat

public static <T> List<T> concat(List<T> inputs,
                                 T newValue)

Concat new value to existing inputs and returns new outputs. Note that input is not modified.

Type Parameters:

T - The type of object.

Parameters:

inputs - Input list.

newValue - The new value to add.

Returns:

The outputs.