HashMap扩容函数解读

void resize(int newCapacity)
{
　　　Entry[] oldTable = table;
　　   int oldCapacity = oldTable.length;
if (oldCapacity == MAXIMUM_CAPACITY)
{
threshold = Integer.MAX_VALUE;
return;
}

Entry[] newTable = new Entry[newCapacity];
transfer(newTable, initHashSeedAsNeeded(newCapacity));
table = newTable;
threshold = (int) Math.min(newCapacity * loadFactor, MAXIMUM_CAPACITY + 1);
}

/**
* Transfers all entries from current table to newTable.
*/
void transfer(Entry[] newTable, boolean rehash)
{
int newCapacity = newTable.length;
for (Entry<K, V> e : table)
{
while (null != e)
{
Entry<K, V> next = e.next;
if (rehash)
{
e.hash = null == e.key ? 0 : hash(e.key);
}
int i = indexFor(e.hash, newCapacity);
e.next = newTable[i];
newTable[i] = e;
e = next;
}
}
}