HashMap是非synchronized,而Hashtable是synchronized,这意味着Hashtable是线程安全的,多个线程可以共享一个Hashtable;而如果没有正确的同步的话,多个线程是不能共享HashMap的。Java 5提供了ConcurrentHashMap,它是HashTable的替代,比HashTable的扩展性更好。 另一个区别是HashMap的迭代器(Iterator)是fail-fast迭代器,而H...
Hashtable是同步的 ,而HashMap则不是。这使得HashMap更适合非线程应用程序,因为非同步对象通常比同步对象执行得更好。 Hashtable不允许使用null键或值。 HashMap允许一个null键和任意数量的null值。 HashMap 的子类之一是LinkedHashMap ,因此如果您想要可预测的迭代顺序(默认情况下是插入顺序),您可以轻松地为Link...
Biggest difference as per my knowledge - Collections(ArrayList, Vector, LinkedList, Queue, Hashtable, TreeMap, LinkedHashMap, LinkedHashSet, TreeSet) play important role in Java; no equivalent in OO ABAP. Internal tables and work area can be used whenever we need collection i.e. to process...
Internet support is built into Java, but not in C++. On the other hand, C++ has support for socket programming which can be used. Java does not support header files and library files. Java usesimportto include different classes and methods. Java does not support default arguments. There is ...
The difference between HashMap and Hashtable is that HashMap particularly implements the Map interface whereas the Hashtable extends the Dictionary class which is a legacy class which is reengineered to implement Map interface. The other important differ
Key Differences Between HashMap and LinkedHashMap in Java The most important difference is that insertion order of the HashMap isnot preservedwhereas, the insertion order of the LinkedHashMap ispreserved. The data structure used by HashMap to store the elements of the map isHashtable. On the...
The main difference between HashMap and Treemap is that the HashMap does not preserve the insertion order whereas, the Treemap does.