Java Doc for LinkedList.java in  » 6.0-JDK-Modules » j2me » java » util » Java Source Code / Java DocumentationJava Source Code and Java Documentation

All of the stack/queue/deque operations could be easily recast in terms of the standard list operations. They're included here primarily for convenience, though they may run slightly faster than the equivalent List operations.

All of the operations perform as could be expected for a doubly-linked list. Operations that index into the list will traverse the list from the begining or the end, whichever is closer to the specified index.

Note that this implementation is not synchronized. If multiple threads access a list concurrently, and at least one of the threads modifies the list structurally, it must be synchronized externally. (A structural modification is any operation that adds or deletes one or more elements; merely setting the value of an element is not a structural modification.) This is typically accomplished by synchronizing on some object that naturally encapsulates the list. If no such object exists, the list should be "wrapped" using the Collections.synchronizedList method. This is best done at creation time, to prevent accidental unsynchronized access to the list:

 List list = Collections.synchronizedList(new LinkedList(...));
 

The iterators returned by the this class's iterator and listIterator methods are fail-fast: if the list is structurally modified at any time after the iterator is created, in any way except through the Iterator's own remove or add methods, the iterator will throw a ConcurrentModificationException. Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future.

Note that the fail-fast behavior of an iterator cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast iterators throw ConcurrentModificationException on a best-effort basis. Therefore, it would be wrong to write a program that depended on this exception for its correctness: the fail-fast behavior of iterators should be used only to detect bugs.

This class is a member of the Java Collections Framework.
author:
   Josh Bloch
version:
   1.39, 10/10/06
See Also:   List
See Also:   ArrayList
See Also:   Vector
See Also:   Collections.synchronizedList(List)
since:
   1.2

The list-iterator is fail-fast: if the list is structurally modified at any time after the Iterator is created, in any way except through the list-iterator's own remove or add methods, the list-iterator will throw a ConcurrentModificationException.

The list-iterator is fail-fast: if the list is structurally modified at any time after the Iterator is created, in any way except through the list-iterator's own remove or add methods, the list-iterator will throw a ConcurrentModificationException. Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future.
Parameters:
  index - index of first element to be returned from thelist-iterator (by a call to next). a ListIterator of the elements in this list (in propersequence), starting at the specified position in the list.
throws:
  IndexOutOfBoundsException - if index is out of range(index < 0 || index > size()).
See Also:   List.listIterator(int)

If the list fits in the specified array with room to spare (i.e., the array has more elements than the list), the element in the array immediately following the end of the collection is set to null. This is useful in determining the length of the list only if the caller knows that the list does not contain any null elements.
Parameters:
  a - the array into which the elements of the list are tobe stored, if it is big enough; otherwise, a new array of thesame runtime type is allocated for this purpose. an array containing the elements of the list.
throws:
  ArrayStoreException - if the runtime type of a is not asupertype of the runtime type of every element in this list.
throws:
  NullPointerException - if the specified array is null.