org.swblocks.jbl.collections

Class CollectionUtils

java.lang.Object

org.swblocks.jbl.collections.CollectionUtils

public class CollectionUtils
extends java.lang.Object

Collection Utilities.

Lightweight utility class for Collections.

Method Summary

Modifier and Type	Method and Description
static boolean	isNotEmpty(java.util.Collection<?> collection) Utility method to check for a not empty Collection including a null check.
static <K,V> boolean	isNotEmpty(java.util.Map<K,V> map) Utility method to check for a not empty Map including a null check.
static <V> java.util.List<V>	unmodifiableList(java.util.List<V> list) Wraps a List with the Collections.unmodifiableList, but only once.
static <K,V> java.util.Map<K,V>	unmodifiableMap(java.util.Map<K,V> map) Wraps a Map with the Collections.unmodifiableMap, but only once.

Methods inherited from class java.lang.Object

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

Method Detail

isNotEmpty

public static boolean isNotEmpty(java.util.Collection<?> collection)

Utility method to check for a not empty Collection including a null check.

Parameters:

collection - Collection to test for non empty

Returns:

true if collection is not null and has at least one entry.

isNotEmpty

public static <K,V> boolean isNotEmpty(java.util.Map<K,V> map)

Utility method to check for a not empty Map including a null check.

Type Parameters:

K - Type of Key in Map

V - Type of Value in Map

Parameters:

map - Map to test for non empty

Returns:

true if map is not null and has at least one entry.

unmodifiableMap

public static <K,V> java.util.Map<K,V> unmodifiableMap(java.util.Map<K,V> map)

Wraps a Map with the Collections.unmodifiableMap, but only once.

Checks the Map passed to ensure that it is not already a Collections.unmodifiableMap. If the parameter is a null or empty, then it returns Collections.emptyMap.

Type Parameters:

K - Key type

V - Value type

Parameters:

map - Map to wrap with Collections.unmodifiableMap

Returns:

An unmodifiable Map

unmodifiableList

public static <V> java.util.List<V> unmodifiableList(java.util.List<V> list)

Wraps a List with the Collections.unmodifiableList, but only once.

Checks the List passed to ensure that it is not already a Collections.unmodifiableLisy. If the parameter is a null or empty, then it returns Collections.emptyList.

Type Parameters:

V - Value type

Parameters:

list - List to wrap with Collections.unmodifiableList

Returns:

An unmodifiable List.