一、总结
1.基于 jdk 1.8 源码分析
2.
二、类声明
/**
* Linked list implementation of the List interface. Implements all
* optional list operations, and permits all elements (including
* null). In addition to implementing the List interface,
* the LinkedList class provides uniformly named methods to
* get, remove and insert an element at the
* beginning and end of the list. These operations allow linked lists to be
* used as a stack, {@linkplain Queue queue}, or {@linkplain Deque
* double-ended queue}.
* 允许所有元素均为 null
*
*
* The class implements the Deque interface, providing
* first-in-first-out queue operations for add,
* poll, along with other stack and deque operations.
* 实现Deque接口，添加元素时如同 先进先出 的队列
*
* 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 beginning or the end, whichever is closer to the specified index.
*
*
Note that this implementation is not synchronized.
* If multiple threads access a linked 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.
* 非线程安全的实现
* If no such object exists, the list should be "wrapped" using the
* {@link Collections#synchronizedList 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 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 {@link
* 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 1.67, 04/21/06
* @see List
* @see ArrayList
* @see Vector
* @since 1.2
* @param the type of elements held in this collection
*/
public class LinkedList
extends AbstractSequentialList
implements List, Deque, Cloneable, java.io.Serializable
1.继承 AbstractSequentialList
2.实现 Deque
二、成员变量及构造方法
//
private transient Entry header = new Entry(null, null, null);
private transient int size = 0;
/**
* Constructs an empty list.
*/
public LinkedList() {
header.next = header.previous = header;
}
/**
* Constructs a list containing the elements of the specified
* collection, in the order they are returned by the collection's
* iterator.
*
* @param c the collection whose elements are to be placed into this list
* @throws NullPointerException if the specified collection is null
*/
public LinkedList(Collection c) {
this();
addAll(c);
}
博文参考：
http://www.cnblogs.com/ITtangtang/p/3948610.html