Is it possible to have number of locks greater than number of buckets in ConcurrentHashMap in Java?

Question

As we know, java's ConcurrentHashMap has a number of internal locks, and each of them guards some region of the bucket's array.

public ConcurrentHashMap(int initialCapacity, loat loadFactor, int concurrencyLevel)

initialCapacity: 16; loadFactory: 0.75f; concurrencyLevel: 16.

ie Default concurrencyLevel and initialCapacity is same.

Is is possible to have more no. of locks than no. of buckets ?

Answer 1

不，CHM使用每个存储桶作为锁（在Java 7之前，每个存储桶都是ReentrantLock现在每个存储桶都将synchronized 。因此，根据定义，不能有更多的锁。