public final class GenericUtils extends Object
Modifier and Type | Field and Description |
---|---|
static Comparator<String> |
CASE_SENSITIVE_ORDER
The complement of
String.CASE_INSENSITIVE_ORDER |
static byte[] |
EMPTY_BYTE_ARRAY |
static Object[] |
EMPTY_OBJECT_ARRAY |
static String[] |
EMPTY_STRING_ARRAY |
static Object |
NULL
A value indicating a
null value - to be used as a placeholder
where null s are not allowed |
static String |
QUOTES |
Modifier and Type | Method and Description |
---|---|
static <T extends Throwable> |
accumulateException(T current,
T extra)
Used to "accumulate" exceptions of the same type.
|
static <T> List<T> |
asList(T... values) |
static <V extends Comparable<V>> |
asSortedSet(Collection<? extends V> values) |
static <V> SortedSet<V> |
asSortedSet(Comparator<? super V> comp,
Collection<? extends V> values) |
static <V> SortedSet<V> |
asSortedSet(Comparator<? super V> comp,
V... values) |
static <V> Factory<SortedMap<String,V>> |
caseInsensitiveMap() |
static <K,V> Map<V,K> |
flipMap(Map<? extends K,? extends V> map,
Factory<? extends Map<V,K>> mapCreator,
boolean allowDuplicates) |
static boolean |
isEmpty(CharSequence cs) |
static boolean |
isEmpty(Collection<?> c) |
static <T> boolean |
isEmpty(Iterable<? extends T> iter) |
static <T> boolean |
isEmpty(Iterator<? extends T> iter) |
static boolean |
isEmpty(Map<?,?> m) |
static <T> boolean |
isEmpty(T... a) |
static <T> Iterator<T> |
iteratorOf(Iterable<T> iterable)
Resolves to an always non-
null iterator |
static <T> Iterator<T> |
iteratorOf(Iterator<T> iter)
Resolves to an always non-
null iterator |
static String |
join(Iterable<?> iter,
char ch) |
static String |
join(Iterable<?> iter,
CharSequence sep) |
static String |
join(Iterator<?> iter,
char ch) |
static String |
join(Iterator<?> iter,
CharSequence sep) |
static <T> String |
join(T[] values,
char ch) |
static <T> String |
join(T[] values,
CharSequence sep) |
static int |
length(CharSequence cs) |
static <T> int |
length(T... a) |
static <K,V> Map<K,V> |
mapValues(Transformer<? super V,? extends K> keyMapper,
Factory<? extends Map<K,V>> mapCreator,
Collection<? extends V> values)
Creates a map out of a group of values
|
static <K,V> Map<K,V> |
mapValues(Transformer<? super V,? extends K> keyMapper,
Factory<? extends Map<K,V>> mapCreator,
V... values) |
static <T> Iterable<T> |
multiIterableSuppliers(Iterable<? extends Supplier<? extends Iterable<? extends T>>> providers) |
static <V extends Comparable<V>> |
naturalComparator() |
static <E extends Enum<E>> |
of(Collection<? extends E> values) |
static <E extends Enum<E>> |
of(E... values) |
static Throwable |
peelException(Throwable t)
Attempts to get to the "effective" exception being thrown,
by taking care of some known exceptions that wrap the original thrown
one.
|
static Throwable |
resolveExceptionCause(Throwable t) |
static int |
safeCompare(String s1,
String s2,
boolean caseSensitive) |
static <T> List<T> |
selectMatchingMembers(Predicate<? super T> acceptor,
Collection<? extends T> values)
Returns a list of all the values that were accepted by a predicate
|
static <T> List<T> |
selectMatchingMembers(Predicate<? super T> acceptor,
T... values)
Returns a list of all the values that were accepted by a predicate
|
static int |
size(Collection<?> c) |
static int |
size(Map<?,?> m) |
static String[] |
split(String s,
char ch) |
static CharSequence |
stripDelimiters(CharSequence s,
char delim) |
static CharSequence |
stripQuotes(CharSequence s) |
static <T> Supplier<T> |
supplierOf(T value)
Wraps a value into a
Supplier |
static String |
trimToEmpty(String s) |
public static final byte[] EMPTY_BYTE_ARRAY
public static final String[] EMPTY_STRING_ARRAY
public static final Object[] EMPTY_OBJECT_ARRAY
public static final Object NULL
null
value - to be used as a placeholder
where null
s are not allowedpublic static final Comparator<String> CASE_SENSITIVE_ORDER
String.CASE_INSENSITIVE_ORDER
public static final String QUOTES
public static int length(CharSequence cs)
public static boolean isEmpty(CharSequence cs)
public static <T> String join(T[] values, char ch)
public static <T> String join(T[] values, CharSequence sep)
public static String join(Iterable<?> iter, CharSequence sep)
public static String join(Iterator<?> iter, CharSequence sep)
public static int size(Collection<?> c)
public static boolean isEmpty(Collection<?> c)
public static int size(Map<?,?> m)
public static boolean isEmpty(Map<?,?> m)
@SafeVarargs public static <T> int length(T... a)
public static <T> boolean isEmpty(Iterable<? extends T> iter)
public static <T> boolean isEmpty(Iterator<? extends T> iter)
@SafeVarargs public static <T> boolean isEmpty(T... a)
@SafeVarargs public static <E extends Enum<E>> Set<E> of(E... values)
public static <E extends Enum<E>> Set<E> of(Collection<? extends E> values)
@SafeVarargs public static <T> List<T> asList(T... values)
public static <V extends Comparable<V>> Comparator<V> naturalComparator()
public static <V extends Comparable<V>> SortedSet<V> asSortedSet(Collection<? extends V> values)
@SafeVarargs public static <V> SortedSet<V> asSortedSet(Comparator<? super V> comp, V... values)
V
- The element typecomp
- The (non-null
) Comparator
to usevalues
- The values to be added (ignored if null
)SortedSet
containing the values (if any) sorted
using the provided comparatorpublic static <V> SortedSet<V> asSortedSet(Comparator<? super V> comp, Collection<? extends V> values)
V
- The element typecomp
- The (non-null
) Comparator
to usevalues
- The values to be added (ignored if null
/empty)SortedSet
containing the values (if any) sorted
using the provided comparatorpublic static <K,V> Map<V,K> flipMap(Map<? extends K,? extends V> map, Factory<? extends Map<V,K>> mapCreator, boolean allowDuplicates)
@SafeVarargs public static <K,V> Map<K,V> mapValues(Transformer<? super V,? extends K> keyMapper, Factory<? extends Map<K,V>> mapCreator, V... values)
public static <K,V> Map<K,V> mapValues(Transformer<? super V,? extends K> keyMapper, Factory<? extends Map<K,V>> mapCreator, Collection<? extends V> values)
keyMapper
- The Transformer
that generates a key for a given value.
If the returned key is null
then the value is not mappedmapCreator
- The Factory
used to create the result map - provided
non-empty group of valuesvalues
- The values to be mappedMap
- Note: no validation is made to ensure
that 2 (or more) values are not mapped to the same key@SafeVarargs public static <T> List<T> selectMatchingMembers(Predicate<? super T> acceptor, T... values)
public static <T> List<T> selectMatchingMembers(Predicate<? super T> acceptor, Collection<? extends T> values)
public static CharSequence stripQuotes(CharSequence s)
s
- The CharSequence
to be checkedQUOTES
on both ends, then they are stripped, otherwise
nothing is donestripDelimiters(CharSequence, char)
public static CharSequence stripDelimiters(CharSequence s, char delim)
s
- The CharSequence
to be checkeddelim
- The expected delimiterpublic static Throwable peelException(Throwable t)
t
- The original Throwable
- ignored if null
public static Throwable resolveExceptionCause(Throwable t)
t
- The original Throwable
- ignored if null
Throwable.getCause()
is non-null
then
the cause, otherwise the original exception - null
if
the original exception was null
public static <T extends Throwable> T accumulateException(T current, T extra)
null
then the new one becomes the current,
otherwise the new one is added as a suppressed exception to the
current oneT
- The exception typecurrent
- The current exceptionextra
- The extra/new exceptionThrowable.addSuppressed(Throwable)
public static <T> Supplier<T> supplierOf(T value)
Supplier
T
- Type of value being suppliedvalue
- The value to be suppliedpublic static <T> Iterator<T> iteratorOf(Iterable<T> iterable)
null
iteratoriterable
- The Iterable
instancenull
iterator which may be empty if no iterable
instance or no iterator returned from ititeratorOf(Iterator)
public static <T> Iterator<T> iteratorOf(Iterator<T> iter)
null
iteratoriter
- The Iterator
instancenull
iterator which may be empty if no iterator instanceCollections.emptyIterator()
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