JDK 9 uses ConcurrentHashMap for mapping ProtectionDomain to PermissionCollection. ConcurrentHashMap is typically used for high concurrency in applications. It has the following characteristics:
- Thread safe
- Enter map does not need to be synchronized
- Fast reads
- Writes use locks
- No object-level locking
- Locking at a very granular level
The ConcurrentHashMap class definition follows:
public class ConcurrentHashMap<K, V> extends AbstractMap<K, V> implements ConcurrentMap<K, V>, Serializable
In the preceding class definition, K refers to the type of keys maintained by the hash map and V indicates the type of mapped values. There is a KeySetView sub-class and several methods.
There are three additional classes related ...
