public
class
CollectionUtil
extends Object| java.lang.Object | |
| ↳ | com.pnfsoftware.jeb.util.collect.CollectionUtil |
Class Overview
Convenience methods for Java Collection collections, in particular, List lists.
Summary
| Public Constructors | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| CollectionUtil() | |||||||||||
| Public Methods | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| static <T> Collection<T> | addNonNulls(Collection<T> dst, T... elts) | ||||||||||
| static <T> Collection<T> | addNonNulls(Collection<T> dst, Collection<? extends T> src) | ||||||||||
| static <T, K extends Comparable<K>> T |
binarySearch(List<T> list, K key, IExtractor<T, K> extractor)
Perform a binary search in an ordered list.
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| static <T, K extends Comparable<K>> int |
binarySearchEx(List<? extends T> list, K key, IExtractor<T, ? extends K> extractor, Comparator<K> cc)
Perform a binary search in an ordered list.
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| static <T> boolean | compare(Collection<? extends T> c1, Collection<? extends T> c2, boolean sorted) | ||||||||||
| static <T> boolean | compareByReference(Collection<? extends T> c1, Collection<? extends T> c2, boolean sorted) | ||||||||||
| static boolean |
contains(Collection<?> c, Object v)
Safely check if an object is present within a collection.
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| static boolean |
containsNonNull(Iterable<?> c)
Determine if the given iterable contains one or more non-null elements.
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| static boolean |
containsNull(Iterable<?> c)
Determine if the given iterable contains one or more null elements.
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| static <T> boolean |
containsReference(Collection<? extends T> c, T o)
Determine if the collection contains the object reference (differs from
contains(Object) by checking reference equality == instead
of equals(Object) equality) | ||||||||||
| static <T> int |
count(Collection<T> coll, T item)
Count elements using
equals(Object). | ||||||||||
| static <T> boolean | hasIntersection(Collection<? extends T> c1, Collection<? extends T> c2) | ||||||||||
| static <T> int |
identityCount(Collection<T> coll, T item)
Count elements using
==. | ||||||||||
| static <T> Set<T> |
intersect(Collection<? extends T> c1, Collection<? extends T> c2)
Return the intersection of 2 collections (order of collection parameters does not matter).
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| static <T> List<T> |
intersection(List<? extends T> c1, List<? extends T> c2)
This method is deprecated.
Use
intersect(Collection, Collection) | ||||||||||
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[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
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Public Constructors
public CollectionUtil ()
Public Methods
public static Collection<T> addNonNulls (Collection<T> dst, T... elts)
public static Collection<T> addNonNulls (Collection<T> dst, Collection<? extends T> src)
public static T binarySearch (List<T> list, K key, IExtractor<T, K> extractor)
Perform a binary search in an ordered list.
Parameters
| list | a list of ordered items |
|---|---|
| key | the ordering key for the items. |
| extractor | key extractor |
Returns
- the element, null if not found
public static int binarySearchEx (List<? extends T> list, K key, IExtractor<T, ? extends K> extractor, Comparator<K> cc)
Perform a binary search in an ordered list.
Parameters
| list | a list of ordered items |
|---|---|
| key | the ordering key for the items. |
| extractor | key extractor |
Returns
- the zero+ index of the found element; else, the negative insertion index of the ghost element
public static boolean compare (Collection<? extends T> c1, Collection<? extends T> c2, boolean sorted)
public static boolean compareByReference (Collection<? extends T> c1, Collection<? extends T> c2, boolean sorted)
public static boolean contains (Collection<?> c, Object v)
Safely check if an object is present within a collection.
Parameters
| c | collection, potentially null |
|---|---|
| v | object, potentially null |
Returns
- true IFF the object is contained in the collection
public static boolean containsNonNull (Iterable<?> c)
Determine if the given iterable contains one or more non-null elements.
public static boolean containsNull (Iterable<?> c)
Determine if the given iterable contains one or more null elements.
public static boolean containsReference (Collection<? extends T> c, T o)
Determine if the collection contains the object reference (differs from
contains(Object) by checking reference equality == instead
of equals(Object) equality)
Parameters
| c | collection to loop into |
|---|---|
| o | element whose presence in this collection is to be tested |
Returns
- true if the collection contains the specified element
public static boolean hasIntersection (Collection<? extends T> c1, Collection<? extends T> c2)
public static int identityCount (Collection<T> coll, T item)
Count elements using ==.
public static Set<T> intersect (Collection<? extends T> c1, Collection<? extends T> c2)
Return the intersection of 2 collections (order of collection parameters does not matter).
Parameters
| c1 | first collection |
|---|---|
| c2 | second collection |
Returns
- a set of intersection
public static List<T> intersection (List<? extends T> c1, List<? extends T> c2)
This method is deprecated.
Use intersect(Collection, Collection)
Return the intersection of 2 lists. May contain duplicated elements.