Package org.camunda.bpm.engine.impl.util

Class CollectionUtil

java.lang.Object

org.camunda.bpm.engine.impl.util.CollectionUtil

public class CollectionUtil
extends Object

helper/convience methods for working with collections.

Author:

Joram Barrez

Method Summary

Modifier and Type	Method	Description
static <S, T> void	addCollectionToMapOfSets(Map<S,Set<T>> map, S key, Collection<T> values)
static <S, T> void	addToMapOfLists(Map<S,List<T>> map, S key, T value)
static <S, T> void	addToMapOfSets(Map<S,Set<T>> map, S key, T value)
static <T> List<T>	asArrayList(T[] values)	Arrays.asList cannot be reliably used for SQL parameters on MyBatis < 3.3.0
static <T> Set<T>	asHashSet(T... elements)
static <T> List<T>	collectInList(Iterator<T> iterator)
static boolean	isEmpty(Collection<?> collection)
static <S, T> void	mergeMapsOfLists(Map<S,List<T>> map, Map<S,List<T>> toAdd)
static <T> List<List<T>>	partition(List<T> list, int partitionSize)	Chops a list into non-view sublists of length partitionSize.
static Map<String,Object>	singletonMap(String key, Object value)	Helper method that creates a singleton map.

Methods inherited from class java.lang.Object

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

Method Details

singletonMap

public static Map<String,Object> singletonMap(String key,
 Object value)

Helper method that creates a singleton map. Alternative for Collections.singletonMap(), since that method returns a generic typed map <K,T> depending on the input type, but we often need a <String, Object> map.

asArrayList

public static <T> List<T> asArrayList(T[] values)

Arrays.asList cannot be reliably used for SQL parameters on MyBatis < 3.3.0

asHashSet

public static <T> Set<T> asHashSet(T... elements)

addToMapOfLists

public static <S,
T> void addToMapOfLists(Map<S,List<T>> map,
 S key,
 T value)

mergeMapsOfLists

public static <S,
T> void mergeMapsOfLists(Map<S,List<T>> map,
 Map<S,List<T>> toAdd)

addToMapOfSets

public static <S,
T> void addToMapOfSets(Map<S,Set<T>> map,
 S key,
 T value)

addCollectionToMapOfSets

public static <S,
T> void addCollectionToMapOfSets(Map<S,Set<T>> map,
 S key,
 Collection<T> values)

partition

public static <T> List<List<T>> partition(List<T> list,
 int partitionSize)

Chops a list into non-view sublists of length partitionSize. Note: the argument list may be included in the result.

collectInList

public static <T> List<T> collectInList(Iterator<T> iterator)

isEmpty

public static boolean isEmpty(Collection<?> collection)