HashMap到concurrentHashMap

Question

我有一个返回HashMap的getHashMap方法。我需要用HashMap填充一个ConcurrentHashMap (在setConcurrentHashMap中)。

有办法做到这一点吗？

示例代码：

//getHashMap return a HashMap<String, String>
Map<String, String> myMap = getHashMap();
TestClass.getSingleton().setConcurrentHashMap(ConcurrentHashMap<String, String> concurrentHashMap)

Answer 1

快速浏览一下javadoc就会发现，ConcurrentHashMap有一个以Map为参数的复制构造函数：

Map<String, String> myMap = getHashMap();
ConcurrentMap<String, String> concurrentMap = new ConcurrentHashMap<> (myMap);

Answer 2

ConcurrentHashMap类提供了一个构造函数，用于从给定的Map创建ConcurrentHashMap。

Map<String, String> myMap = getHashMap();
TestClass.getSingleton()
    .setConcurrentHashMap(new ConcurrentHashMap<String, String>(myMap));