Hashtable的实现原理跟HashMap的实现原理(Java 8之前)是一样的,里面的数据结构同样是一个数组+链表的结构。首先来看一下put的源码 /** * Maps the specified <code>key</code> to the specified * <code>value</code> in this hashtable. Neither the key nor the * value can be <code>null</code>....
* <code>null</code> *@seeObject#equals(Object) *@see#get(Object)*/publicsynchronizedV put(K key, V value) {//Make sure the value is not nullif(value ==null) {thrownewNullPointerException(); }//Makes sure the key is not already in the hashtable.Entry tab[] =table;inthash =key....
>[] oldMap = table; // overflow-conscious code int newCapacity = (oldCapacity << 1) + 1; 说明扩容方案是 扩2倍+1 if (newCapacity - MAX_ARRAY_SIZE > 0) { 如果扩容后大于最大数组大小,就用最大数组大小 if (oldCapacity == MAX_ARRAY_SIZE) // Keep running with MAX_ARRAY_SIZE bucket...
,?>[] oldMap = table;// overflow-conscious code// 扩容成2倍+1intnewCapacity=(oldCapacity <<1) +1;// 这里判断是否超出了容量限制if(newCapacity - MAX_ARRAY_SIZE >0) {if(oldCapacity == MAX_ARRAY_SIZE)// Keep running with MAX_ARRAY_SIZE bucketsreturn;// 最大容量 MAX_ARRAY_SIZEnewC...
代码语言:java AI代码解释 publicsynchronizedVput(Kkey,Vvalue){// Make sure the value is not nullif(value==null){thrownewNullPointerException();}// Increase the modCountmodCount++;// Resize the Hashtable if necessaryif(count>=threshold){resize(2*table.length);}// Get the hash code of th...
Java的HashMap和HashTable 1. HashMap 1) hashmap的数据结构 Hashmap是一个数组和链表的结合体(在数据结构称“链表散列“),如下图示: 当我们往hashmap中put元素的时候,先根据key的hash值得到这个元素在数组中的位置(即下标),然后就可以把这个元素放到对应的位置中了。如果这个元素所在的位子上已经存放有其他元素...
hashCode()Returns the hash code value for this Map as per the definition in the Map interface.booleanisEmpty()Tests if this hashtable maps no keys to values.Enumeration<K>keys()Returns an enumeration of the keys in this hashtable.Set<K>keySet()...
hashCodein interfaceMap<K,V> Overrides: hashCodein classObject Returns: a hash code value for this object. Since: 1.2 See Also: Map.hashCode() compute publicVcompute(Kkey,BiFunction<? superK,? superV,? extendsV> remappingFunction) ...
cn/2024/12/25/leveldb_source_hashtable/jdk11 hashtable扩容是这么写的// overflow-conscious code...
HashTable https://blog.csdn.net/ns_code/article/details/36191279 value不允许为空 public synchronized V put(K key, V value) { // Make sure the value is not null if (value == null) { throw new NullPointerException(); } // Makes sure the key is not already in the hashtable. Entr...