concurrent introduction
The concurrent package for Java is an important toolset for building efficient, scalable, and robust multithreaded applications, while efficiently managing the complexities of concurrent programming. However, it is crucial to understand the principles of concurrent programming and to use these tools carefully to avoid common problems such as race conditions and deadlocks.
The main content scope of Java concurrent package
1. Thread and Runnable:
Java allows you to create and manage threads using the Thread class or implementing the Runnable interface. A thread represents a single path of execution in a Java program.
2. Executors：
The Executor framework provides a higher-level abstraction for managing the execution of threads. It includes interfaces such as Executor, ExecutorService and ScheduledExecutorService, which are used to manage the thread pool and process the execution of tasks asynchronously.
3. Thread pool:
A thread pool manages a set of worker threads that can be reused to perform multiple tasks. Creating a thread pool through ExecutorService helps to improve performance and manage resources efficiently.
4. Synchronization:
To ensure thread safety and avoid data corruption, Java provides synchronization mechanisms, such as the synchronized keyword, Lock interface, ReentrantLock, ReadWriteLock, etc. These mechanisms allow access to shared resources to be controlled in a multithreaded environment.
5. Thread-safe data structures:
Java provides thread-safe versions of common data structures such as ConcurrentHashMap, ConcurrentLinkedQueue, and CopyOnWriteArrayList. These structures allow multiple threads to safely access them without external synchronization.
6. Atomic variables:
Classes such as AtomicInteger, AtomicLong, and AtomicReference provide atomic operations, ensuring that operations on these variables are performed in an indivisible manner without interference from other threads.
7. Thread coordination:
Java provides several mechanisms for coordinating threads, such as CountDownLatch, CyclicBarrier, Semaphore, and Exchanger. These mechanisms help to synchronize the execution of threads, causing them to wait until certain conditions are met.
8. CompletableFuture：
This class supports asynchronous programming, represents future results of computations, and can be composed and chained together to create more complex asynchronous workflows.
9. Fork/Join framework:
ForkJoinPool and related classes support divide-and-conquer parallel processing tasks, especially suitable for recursive algorithms that can take advantage of multiple cores.