org.kuali.common.util

Class CollectionUtils

java.lang.Object

org.kuali.common.util.CollectionUtils

public class CollectionUtils
extends Object

Constructor Summary

Constructors

Constructor and Description
CollectionUtils()

Method Summary

Methods

Modifier and Type	Method and Description
static String	asCSV(List<String> strings)
static List<Class<?>>	asList(Class<?>... classes) Null safe method for converting an untyped array of classes into a list.
static List<Object>	asList(Object... objects) Null safe method for converting an array of objects into a list.
static <T> List<T>	combine(List<T> list1, List<T> list2) Return a new list containing all of the elements from the lists passed in
static <T> List<T>	combine(List<T> list1, List<T> list2, List<T> list3)
static <K,V> void	combine(Map<K,V> map, List<K> keys, List<V> values) Add keys and values to map.
static <T> List<T>	combine(T element, List<T> list) Return a combined list where required is always the first element in the list
static <T> List<T>	combineLists(List<List<T>> listOfLists) Combine the list of lists into a single list
static <K,V> Map<K,V>	combineMaps(List<Map<K,V>> listOfMaps) Combine the list of maps into a single map
static List<String>	combineStrings(List<String>... lists) Return a new list containing all of the strings from both lists
static List<String>	combineStrings(List<String> list1, List<String> list2) Return a new list containing all of the strings from both lists
static List<String>	combineStrings(List<String> list1, List<String> list2, List<String> list3)
static List<String>	combineStrings(List<String> list1, String string, List<String> list2) Return a new list containing all of the strings from both lists with string added in between the strings from both lists
static List<String>	combineStringsUniquely(List<String> list1, List<String> list2) Return a new list containing the unique set of strings contained in both lists
static boolean	containsAny(String s, List<String> strings) Return true if s contains any of the strings from strings
static List<String>	filter(Collection<String> strings, StringFilter filter) Deprecated.
static List<String>	filterAndSort(List<String> strings, StringFilter filter) Deprecated.
static List<String>	filterAndSortStrings(List<String> strings, StringFilter filter) Remove any Strings from the list that do not match the filter and then sort the ones that remain
static List<String>	filterStrings(Collection<String> strings, StringFilter filter) Remove any Strings from the collection that do not match the filter
static Collection<String>	getBlanks(Collection<String> collection)
static String	getCSV(List<String> strings)
static int[]	getDivideEvenly(int number, int howManyWays) Return an array of int's that represents as even of a split as possible For example: passing in 100,7 returns 15, 15, 14, 14, 14, 14, 14
static List<String>	getLines(String s)
static <T> List<T>	getList(List<Boolean> includes, List<T> list) Return a list containing only the elements where the corresponding index in the includes list is true.
protected static <T> T	getNewInstance(Class<T> c)
static <T> List<T>	getNewList(Class<T> c, int size) Create a new list containing new instances of c
static List<String>	getNoneSensitiveListFromCSV(String csv) If the CSV is whitespace, the empty string, null, "null", or "none", return an empty list.
static <T> List<T>	getPreFilledList(int size, T value)
static List<String>	getSequencedStrings(List<String> strings) Prefix the strings passed in with their position in the list (left padded with zero's).
static List<String>	getSequencedStrings(List<String> strings, int initialSequenceNumber) Prefix the strings passed in with their position in the list (left padded with zero's).
static String	getSpaceSeparatedCSV(List<String> strings)
static String	getSpaceSeparatedString(List<?> list)
static String	getStringWithSeparator(List<?> list, String separator)
static List<String>	getTrimmedListFromCSV(String csv)
static List<File>	getUniqueFiles(List<File> files)
static List<String>	getUniqueStrings(List<String> strings) Return a new List containing the unique set of strings from strings
static boolean	hasBlanks(Collection<String> collection)
static boolean	isEmpty(Collection<?> c)
static boolean	isEmpty(Map<?,?> m)
static <T> void	nullSafeAdd(List<T> list1, List<T> list2)
static <T> List<T>	nullSafeCombine(List<T> list1, List<T> list2)
static <T> List<T>	singletonList(T o) Returns an immutable list containing only the specified object.
static List<String>	sortedMerge(List<String> list, String csv)
static <T> List<List<T>>	splitEvenly(List<T> elements, int howManyWays) Split elements evenly into separate lists divided up howManyWays
static String	toCSV(List<Integer> integers)
static <T> List<T>	toEmptyList(List<T> list) If list==null return an empty list otherwise return list
static <T> List<T>	toEmptyList(T o) If o==null return Collections.<T> emptyList() otherwise return Collections.singletonList(o)
static <K,V> Map<K,V>	toEmptyMap(K key, V value) If key==null OR value==null return an empty map otherwise return a singleton map.
static <K,V> Map<K,V>	toEmptyMap(Map<K,V> map) If map==null return emptyMap(), otherwise return map
static <K,V> Map<K,V>	toModifiableEmptyMap(K key, V value) If key==null OR value==null return new HashMap() otherwise return new HashMap(Collections.singletonMap(key, value))
static <K,V> Map<K,V>	toModifiableEmptyMap(Map<K,V> map) If map==null return new HashMap(), otherwise return map
static <T> Collection<T>	toNullIfEmpty(Collection<T> c)
static <T> List<T>	toNullIfEmpty(List<T> list)
static Object[]	toObjectArray(List<Object> objects)
static String[]	toStringArray(List<String> strings)
static <T> List<T>	unmodifiableCopy(List<T> list) Deprecated. See ListUtils.newArrayList() instead
static <T> List<T>	unmodifiableList(T... elements) Deprecated. Use ImmutableList.copyOf(elements) instead
static <T> List<T>	unmodifiableList(T element) Deprecated. Use CollectionUtils.singletonList() instead

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionUtils

public CollectionUtils()

Method Detail

hasBlanks

public static boolean hasBlanks(Collection<String> collection)

getBlanks

public static Collection<String> getBlanks(Collection<String> collection)

unmodifiableCopy

@Deprecated
public static <T> List<T> unmodifiableCopy(List<T> list)

Deprecated. See ListUtils.newArrayList() instead

Returns a new unmodifiable list containing the elements from list

unmodifiableList

@Deprecated
public static <T> List<T> unmodifiableList(T element)

Deprecated. Use CollectionUtils.singletonList() instead

Get an unmodifiable list from the single element. Return emptyList() if element is null.

unmodifiableList

@Deprecated
@SafeVarargs
public static <T> List<T> unmodifiableList(T... elements)

Deprecated. Use ImmutableList.copyOf(elements) instead

Get an unmodifiable list from elements

getNoneSensitiveListFromCSV

public static List<String> getNoneSensitiveListFromCSV(String csv)

If the CSV is whitespace, the empty string, null, "null", or "none", return an empty list.

filterAndSort

@Deprecated
public static List<String> filterAndSort(List<String> strings,
                                    StringFilter filter)

Deprecated.

Remove any Strings from the list that do not match the filter and then sort the ones that remain

Returns:

The list of strings that were filtered out.

filterAndSortStrings

public static List<String> filterAndSortStrings(List<String> strings,
                                StringFilter filter)

Remove any Strings from the list that do not match the filter and then sort the ones that remain

Returns:

The list of strings that were filtered out.

filterStrings

public static List<String> filterStrings(Collection<String> strings,
                         StringFilter filter)

Remove any Strings from the collection that do not match the filter

filter

@Deprecated
public static List<String> filter(Collection<String> strings,
                             StringFilter filter)

Deprecated.

Remove any Strings from the collection that do not match the filter

asList

public static List<Object> asList(Object... objects)

Null safe method for converting an array of objects into a list. Never returns null.

asList

public static List<Class<?>> asList(Class<?>... classes)

Null safe method for converting an untyped array of classes into a list. Never returns null.

getDivideEvenly

public static int[] getDivideEvenly(int number,
                    int howManyWays)

Return an array of int's that represents as even of a split as possible For example: passing in 100,7 returns 15, 15, 14, 14, 14, 14, 14

Parameters:

numerator -

denominator -

Returns:

splitEvenly

public static final <T> List<List<T>> splitEvenly(List<T> elements,
                            int howManyWays)

Split elements evenly into separate lists divided up howManyWays

getSequencedStrings

public static final List<String> getSequencedStrings(List<String> strings,
                               int initialSequenceNumber)

Prefix the strings passed in with their position in the list (left padded with zero's). The padding is the number of digits in the size of the list. A list with 100 elements will return strings prefixed with 000, 001, etc.

getSequencedStrings

public static final List<String> getSequencedStrings(List<String> strings)

Prefix the strings passed in with their position in the list (left padded with zero's). The padding is the number of digits in the size of the list. A list with 100 elements will return strings prefixed with 000, 001, etc.

getUniqueStrings

public static final List<String> getUniqueStrings(List<String> strings)

Return a new List containing the unique set of strings from strings

getUniqueFiles

public static final List<File> getUniqueFiles(List<File> files)

getLines

public static final List<String> getLines(String s)

combineStringsUniquely

public static final List<String> combineStringsUniquely(List<String> list1,
                                  List<String> list2)

Return a new list containing the unique set of strings contained in both lists

getNewInstance

protected static final <T> T getNewInstance(Class<T> c)

getNewList

public static final <T> List<T> getNewList(Class<T> c,
                     int size)

Create a new list containing new instances of c

getList

public static final <T> List<T> getList(List<Boolean> includes,
                  List<T> list)

Return a list containing only the elements where the corresponding index in the includes list is true. includes and list must be the same size.

combineLists

public static final <T> List<T> combineLists(List<List<T>> listOfLists)

Combine the list of lists into a single list

combineMaps

public static final <K,V> Map<K,V> combineMaps(List<Map<K,V>> listOfMaps)

Combine the list of maps into a single map

combine

public static final <T> List<T> combine(T element,
                  List<T> list)

Return a combined list where required is always the first element in the list

toEmptyMap

public static final <K,V> Map<K,V> toEmptyMap(Map<K,V> map)

If map==null return emptyMap(), otherwise return map

toModifiableEmptyMap

public static final <K,V> Map<K,V> toModifiableEmptyMap(Map<K,V> map)

If map==null return new HashMap(), otherwise return map

toModifiableEmptyMap

public static final <K,V> Map<K,V> toModifiableEmptyMap(K key,
                                  V value)

If key==null OR value==null return new HashMap() otherwise return new HashMap(Collections.singletonMap(key, value))

toEmptyMap

public static final <K,V> Map<K,V> toEmptyMap(K key,
                        V value)

If key==null OR value==null return an empty map otherwise return a singleton map.

toEmptyList

public static final <T> List<T> toEmptyList(T o)

If o==null return Collections.<T> emptyList() otherwise return Collections.singletonList(o)

singletonList

public static final <T> List<T> singletonList(T o)

Returns an immutable list containing only the specified object. The returned list is serializable.

Throws:

IllegalArgumentException - if object is null

combine

public static final <K,V> void combine(Map<K,V> map,
                 List<K> keys,
                 List<V> values)

Add keys and values to map. Keys and values must be the same size (or both null). Map cannot be null.

toEmptyList

public static final <T> List<T> toEmptyList(List<T> list)

If list==null return an empty list otherwise return list

toNullIfEmpty

public static final <T> List<T> toNullIfEmpty(List<T> list)

toNullIfEmpty

public static final <T> Collection<T> toNullIfEmpty(Collection<T> c)

getPreFilledList

public static final <T> List<T> getPreFilledList(int size,
                           T value)

getSpaceSeparatedCSV

public static final String getSpaceSeparatedCSV(List<String> strings)

getStringWithSeparator

public static final String getStringWithSeparator(List<?> list,
                            String separator)

toCSV

public static final String toCSV(List<Integer> integers)

asCSV

public static final String asCSV(List<String> strings)

getCSV

public static final String getCSV(List<String> strings)

getSpaceSeparatedString

public static final String getSpaceSeparatedString(List<?> list)

toObjectArray

public static final Object[] toObjectArray(List<Object> objects)

toStringArray

public static final String[] toStringArray(List<String> strings)

isEmpty

public static final boolean isEmpty(Collection<?> c)

isEmpty

public static final boolean isEmpty(Map<?,?> m)

sortedMerge

public static final List<String> sortedMerge(List<String> list,
                       String csv)

getTrimmedListFromCSV

public static final List<String> getTrimmedListFromCSV(String csv)

nullSafeCombine

public static final <T> List<T> nullSafeCombine(List<T> list1,
                          List<T> list2)

combineStrings

public static final List<String> combineStrings(List<String> list1,
                          List<String> list2,
                          List<String> list3)

combineStrings

public static final List<String> combineStrings(List<String> list1,
                          String string,
                          List<String> list2)

Return a new list containing all of the strings from both lists with string added in between the strings from both lists

combineStrings

public static final List<String> combineStrings(List<String> list1,
                          List<String> list2)

Return a new list containing all of the strings from both lists

combineStrings

@SafeVarargs
public static final List<String> combineStrings(List<String>... lists)

Return a new list containing all of the strings from both lists

combine

public static final <T> List<T> combine(List<T> list1,
                  List<T> list2)

Return a new list containing all of the elements from the lists passed in

combine

public static final <T> List<T> combine(List<T> list1,
                  List<T> list2,
                  List<T> list3)

nullSafeAdd

public static final <T> void nullSafeAdd(List<T> list1,
                   List<T> list2)

containsAny

public static final boolean containsAny(String s,
                  List<String> strings)

Return true if s contains any of the strings from strings