concurrent-locks | Upgradable read-write locks for Java | Hashing library

concurrent-locks is a Java library typically used in Security, Hashing applications. concurrent-locks has no bugs, it has no vulnerabilities, it has a Permissive License and it has low support. However concurrent-locks build file is not available. You can download it from GitHub.

The ReentrantReadWriteUpdateLock in this project provides a third type of lock, an update lock. An update lock is an intermediate type of lock between a read lock and a write lock. Like the write lock, only one thread can acquire an update lock at a time. But like a read lock, it allows read access to the thread which holds it, and concurrently to other threads which hold regular read locks. The key feature is that the update lock can be upgraded from its read-only status, to a write lock. Thus it supports read-before-write access patterns efficiently. Also the write lock can be downgraded again to an update lock, supporting write-before-read access patterns efficiently. The following table shows the situations in which the Read-Write-Update lock provided in this project can increase concurrency in applications with read-before-write access patterns. It should also be noted that if the writing thread determines that the document does not need to be updated after all, then it does not upgrade to a write lock and so concurrent reads will not be blocked at all.