public class CollectionUtil
extends java.lang.Object
Constructor and Description |
---|
CollectionUtil() |
Modifier and Type | Method and Description |
---|---|
static <T> java.util.List<T> |
add(java.util.List<T> l,
T o)
Append
o to l , returning l . |
static <T,U> boolean |
equals(java.util.Collection<T> a,
java.util.Collection<U> b)
Return true if
a and b are
pointer equal, or if iterators over both return the same
sequence of pointer equal elements. |
static <T,U extends T,V extends T> |
firstOrElse(java.util.Collection<U> l,
V alt) |
static <T> java.util.List<T> |
list()
Return an empty list.
|
static <T> java.util.List<T> |
list(T o)
Return a singleton list containing
o . |
static <T> java.util.List<T> |
list(T o1,
T o2)
Return a list containing
o1 and o2 . |
static <T> java.util.List<T> |
list(T o1,
T o2,
T o3)
Return a list containing
o1 , ..., o3 . |
static <T> java.util.List<T> |
list(T o1,
T o2,
T o3,
T o4)
Return a list containing
o1 , ..., o4 . |
static <T,U> java.util.List<U> |
map(java.util.List<T> l,
Transformation<T,U> t)
Apply
t to each element of l . |
static <T> java.util.List<T> |
nonNullList(java.util.List<T> l)
Return an empty non-null list if the argument list is null.
|
static <T> java.util.Iterator<Pair<T,T>> |
pairs(java.util.Collection<T> l) |
public static <T> java.util.List<T> add(java.util.List<T> l, T o)
o
to l
, returning l
.public static <T,U> boolean equals(java.util.Collection<T> a, java.util.Collection<U> b)
a
and b
are
pointer equal, or if iterators over both return the same
sequence of pointer equal elements.public static <T> java.util.List<T> list()
public static <T> java.util.List<T> list(T o)
o
.public static <T> java.util.List<T> list(T o1, T o2)
o1
and o2
.public static <T> java.util.List<T> list(T o1, T o2, T o3)
o1
, ..., o3
.public static <T> java.util.List<T> list(T o1, T o2, T o3, T o4)
o1
, ..., o4
.public static <T,U extends T,V extends T> T firstOrElse(java.util.Collection<U> l, V alt)
public static <T> java.util.Iterator<Pair<T,T>> pairs(java.util.Collection<T> l)
public static <T,U> java.util.List<U> map(java.util.List<T> l, Transformation<T,U> t)
t
to each element of l
.
l
is not modified.public static <T> java.util.List<T> nonNullList(java.util.List<T> l)
l
- a possibly null list