PrimitiveIterator

AI-generated Key Takeaways

• PrimitiveIterator is a base type for specialized Iterator implementations for primitive data types (int, long, and double).

• It provides a mechanism to iterate over primitive values without boxing, enhancing performance.

• Specialized subtypes, like PrimitiveIterator.OfInt, offer methods such as nextInt() for direct access to primitive values.

• While default next() implementations box primitive values, using primitive-specific methods is recommended for efficiency.

• forEachRemaining() method processes all remaining elements with a specified action, until completion or an exception is encountered.

public interface PrimitiveIterator implements Iterator<T>

Known Indirect Subclasses PrimitiveIterator.OfDouble, PrimitiveIterator.OfInt, PrimitiveIterator.OfLong PrimitiveIterator.OfDouble An Iterator specialized for double values.  PrimitiveIterator.OfInt An Iterator specialized for int values.  PrimitiveIterator.OfLong An Iterator specialized for long values.

A base type for primitive specializations of Iterator. Specialized subtypes are provided for int, long, and double values.

The specialized subtype default implementations of Iterator.next() and Iterator.forEachRemaining(java.util.function.Consumer) box primitive values to instances of their corresponding wrapper class. Such boxing may offset any advantages gained when using the primitive specializations. To avoid boxing, the corresponding primitive-based methods should be used. For example, PrimitiveIterator.OfInt.nextInt() and PrimitiveIterator.OfInt.forEachRemaining(java.util.function.IntConsumer) should be used in preference to PrimitiveIterator.OfInt.next() and Iterator.forEachRemaining(java.util.function.Consumer).

Iteration of primitive values using boxing-based methods next() and forEachRemaining(), does not affect the order in which the values, transformed to boxed values, are encountered.

Nested Class Summary

interface	PrimitiveIterator.OfDouble		An Iterator specialized for double values.
interface	PrimitiveIterator.OfInt		An Iterator specialized for int values.
interface	PrimitiveIterator.OfLong		An Iterator specialized for long values.

Public Method Summary

abstract void

forEachRemaining(T_CONS action) Performs the given action for each remaining element, in the order elements occur when iterating, until all elements have been processed or the action throws an exception.

Inherited Method Summary

From interface java.util.Iterator

void	forEachRemaining(Consumer<? super E> action) Performs the given action for each remaining element until all elements have been processed or the action throws an exception.
abstract boolean	hasNext() Returns true if the iteration has more elements.
abstract T	next() Returns the next element in the iteration.
void	remove() Removes from the underlying collection the last element returned by this iterator (optional operation).

Public Methods

public abstract void forEachRemaining (T_CONS action)

Performs the given action for each remaining element, in the order elements occur when iterating, until all elements have been processed or the action throws an exception. Errors or runtime exceptions thrown by the action are relayed to the caller.

Parameters

action	The action to be performed for each element

Throws

NullPointerException	if the specified action is null