1 public V get(Object key) {
2 Node<K,V>[] tab; Node<K,V> e, p; int n, eh; K ek;
3 //寻址
4 int h = spread(key.hashCode());
5 if ((tab = table) != null && (n = tab.length) > 0 &&
6 (e = tabAt(tab, (n - 1) & h)) != null) {
7 //当头节点的hash值与key的hash值相同时，判断key的内容知否相同
8 if ((eh = e.hash) == h) {
9 if ((ek = e.key) == key || (ek != null && key.equals(ek)))
10 return e.val;
11 }
12 //如果头节点的hash值eh<0 红黑树存储 直接寻找
13 else if (eh < 0)
14 return (p = e.find(h, key)) != null ? p.val : null;
15 //链表查找
16 while ((e = e.next) != null) {
17 if (e.hash == h &&
18 ((ek = e.key) == key || (ek != null && key.equals(ek))))
19 return e.val;
20 }
21 }
22 return null;
23 }
