RandomAccess
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Known Indirect Subclasses
ArrayList<E> |
Resizable-array implementation of the List interface. |
CopyOnWriteArrayList<E> |
A thread-safe variant of ArrayList in which all mutative
operations (add , set , and so on) are implemented by
making a fresh copy of the underlying array. |
Stack<E> |
The Stack class represents a last-in-first-out
(LIFO) stack of objects. |
Vector<E> |
The Vector class implements a growable array of
objects. |
|
Marker interface used by List implementations to indicate that
they support fast (generally constant time) random access. The primary
purpose of this interface is to allow generic algorithms to alter their
behavior to provide good performance when applied to either random or
sequential access lists.
The best algorithms for manipulating random access lists (such as
ArrayList) can produce quadratic behavior when applied to
sequential access lists (such as LinkedList). Generic list
algorithms are encouraged to check whether the given list is an
instanceof this interface before applying an algorithm that would
provide poor performance if it were applied to a sequential access list,
and to alter their behavior if necessary to guarantee acceptable
performance.
It is recognized that the distinction between random and sequential
access is often fuzzy. For example, some List implementations
provide asymptotically linear access times if they get huge, but constant
access times in practice. Such a List implementation
should generally implement this interface. As a rule of thumb, a
List implementation should implement this interface if,
for typical instances of the class, this loop:
for (int i=0, n=list.size(); i < n; i++)
list.get(i);
runs faster than this loop:
for (Iterator i=list.iterator(); i.hasNext(); )
i.next();
This interface is a member of the
Java Collections Framework.
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Last updated 2024-07-10 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2024-07-10 UTC."],[[["`RandomAccess` is a marker interface signaling that a `List` implementation supports fast, generally constant-time random access."],["It helps generic algorithms optimize their behavior for random or sequential access lists, improving performance."],["Lists should implement `RandomAccess` if indexed access (`list.get(i)`) is faster than iterating using an iterator (`i.next()`)."],["This interface is part of the Java Collections Framework."]]],["The `RandomAccess` interface is a marker for `List` implementations, indicating support for fast, constant-time random access. Generic algorithms should check for this interface and adapt their behavior to ensure efficiency. Lists implementing `RandomAccess`, like `ArrayList`, perform faster with indexed access (`list.get(i)`) than with iterators, while sequential access lists perform better with iterators. Indirect subclasses include `ArrayList`, `CopyOnWriteArrayList`, `Stack`, and `Vector`.\n"]]