Package java8.util

Provides some of the new java.util classes and implementations of static and default interface methods added in Java 8 and, in addition, the JEP 269: Convenience Factory Methods for Collections that were introduced in Java 9.

See: Description

Interface Summary

Interface	Description
PrimitiveIterator<T,T_CONS>	A base type for primitive specializations of Iterator.
PrimitiveIterator.OfDouble	An Iterator specialized for double values.
PrimitiveIterator.OfInt	An Iterator specialized for int values.
PrimitiveIterator.OfLong	An Iterator specialized for long values.
Spliterator<T>	An object for traversing and partitioning elements of a source.
Spliterator.OfDouble	A Spliterator specialized for double values.
Spliterator.OfInt	A Spliterator specialized for int values.
Spliterator.OfLong	A Spliterator specialized for long values.
Spliterator.OfPrimitive<T,T_CONS,T_SPLITR extends Spliterator.OfPrimitive<T,T_CONS,T_SPLITR>>	A Spliterator specialized for primitive values.

Class Summary

Class	Description
Comparators	A place for static default implementations of the new Java 8 default interface methods and static interface methods in the Comparator interface.
DoubleSummaryStatistics	A state object for collecting statistics such as count, min, max, sum, and average.
IntSummaryStatistics	A state object for collecting statistics such as count, min, max, sum, and average.
Iterators	A place for static default implementations of the new Java 8 default interface methods and static interface methods in the Iterator interface.
J8Arrays	A place for the new Arrays methods added in Java 8 and Java 9 (partially) to Java 11 (especially the new parallel and spliterator methods of Java 8).
Lists	A place for static default implementations of the new Java 8 default interface methods and static interface methods in the List interface and, in addition, the JEP 269 "Unmodifiable List Static Factory Methods" in the List interface that were introduced in Java 9.
LongSummaryStatistics	A state object for collecting statistics such as count, min, max, sum, and average.
Maps	A place for static default implementations of the new Java 8 default interface methods and static interface methods in the Map interface and, in addition, the JEP 269 "Unmodifiable Map Static Factory Methods" in the Map interface that were introduced in Java 9.
Maps.Entry	A place for the static interface methods of the Java 8 Map.Entry interface.
Objects	This class consists of static utility methods for operating on objects, or checking certain conditions before operation.
Optional<T>	A container object which may or may not contain a non-null value.
OptionalDouble	A container object which may or may not contain a double value.
OptionalInt	A container object which may or may not contain an int value.
OptionalLong	A container object which may or may not contain a long value.
Sets	A place for the new Java 9 JEP 269 "Unmodifiable Set Static Factory Methods" in the Set interface.
Spliterators	Static classes and methods for operating on or creating instances of Spliterator and its primitive specializations Spliterator.OfInt, Spliterator.OfLong, and Spliterator.OfDouble.
Spliterators.AbstractDoubleSpliterator	An abstract Spliterator.OfDouble that implements trySplit to permit limited parallelism.
Spliterators.AbstractIntSpliterator	An abstract Spliterator.OfInt that implements trySplit to permit limited parallelism.
Spliterators.AbstractLongSpliterator	An abstract Spliterator.OfLong that implements trySplit to permit limited parallelism.
Spliterators.AbstractSpliterator<T>	An abstract Spliterator that implements trySplit to permit limited parallelism.
Spliterators.OfDouble	Static default implementations for the Java 8 default methods of Spliterator.OfDouble
Spliterators.OfInt	Static default implementations for the Java 8 default methods of Spliterator.OfInt
Spliterators.OfLong	Static default implementations for the Java 8 default methods of Spliterator.OfLong
Spliterators.OfPrimitive	Static default implementations for the Java 8 default method of Spliterator.OfPrimitive
SplittableRandom	A generator of uniform pseudorandom values applicable for use in (among other contexts) isolated parallel computations that may generate subtasks.
StringJoiner	StringJoiner is used to construct a sequence of characters separated by a delimiter and optionally starting with a supplied prefix and ending with a supplied suffix.

Package java8.util Description

Provides some of the new java.util classes and implementations of static and default interface methods added in Java 8 and, in addition, the JEP 269: Convenience Factory Methods for Collections that were introduced in Java 9.

Unmodifiable collections

An unmodifiable collection is a collection, all of whose mutator methods are specified to throw UnsupportedOperationException. Such a collection thus cannot be modified by calling any methods on it. For a collection to be properly unmodifiable, any view collections derived from it must also be unmodifiable. For example, if a List is unmodifiable, the List returned by List.subList is also unmodifiable.

An unmodifiable collection is not necessarily immutable. If the contained elements are mutable, the entire collection is clearly mutable, even though it might be unmodifiable. For example, consider two unmodifiable lists containing mutable elements. The result of calling list1.equals(list2) might differ from one call to the next if the elements had been mutated, even though both lists are unmodifiable. However, if an unmodifiable collection contains all immutable elements, it can be considered effectively immutable.

Since:

1.8