好像也不是基于链表来实现的，而是采用与链表类似的节点形式重新定义了一个节点内部类，以此来实现映射
public class LinkedListMap<K, V> implements Map<K, V> {
private class Node{
public K key;
public V value;
public Node next;
public Node(K key,V value, Node next) {
this.key = key;
this.value = value;
this.next = next;
}
public Node(K key) {
this(key, null, null);
}
public Node() {
this(null, null, null);
}
@Override
public String toString() {
return key.toString() + " : " + value.toString();
}
}
private Node dummyHead;
private int size;
private Node getNode(K key) {
Node cur = dummyHead.next;
while(cur != null) {
if(cur.key.equals(key)) {
return cur;
}
cur = cur.next;
}
return null;
}
@Override
public void add(K key, V value) {
//key具有唯一性
Node node = getNode(key);
if(node == null) {
//??????????
dummyHead.next = new Node(key, value, dummyHead.next);
size ++;
}else {
node.value = value;
}
}
@Override
public V remove(K key) {
Node prev = dummyHead;
while(prev.next != null) {
if(prev.next.key.equals(key)) {
break;
}
prev = prev.next;
}
if(prev.next != null) {
Node cur = prev.next;
prev.next = cur.next;
cur.next = null;
size --;
return cur.value;
}
return null;
}
@Override
public boolean contains(K key) {
// TODO Auto-generated method stub
return getNode(key) != null;
}
@Override
public V get(K key) {
Node node = getNode(key);
return node == null ? null : node.value;
}
@Override
public void set(K key, V newValue) {
Node node = getNode(key);
if(node == null)
throw new IllegalArgumentException(key + "doesn't exist!");
node.value = newValue;
}
@Override
public int getSize() {
// TODO Auto-generated method stub
return size;
}
@Override
public boolean inEmpty() {
// TODO Auto-generated method stub
return size == 0;
}
}