ChillDev Commons Concurrent: Precautions for use in thread pool in the Java class library
ChillDev Commons Concurrent: Precautions for use in thread pool in the Java class library
Overview:
The thread pool is a complicated programming tool commonly used in Java development. It can flexibly manage the execution of concurrent tasks by maintaining a thread pool.In the ChillDev Commons Concurrent class library, the use of the thread pool has been simplified and enhanced, but it also needs to pay attention to several precautions to ensure the stability and performance of the program.
1. Reasonable setting thread pool size: When using the thread pool in ChillDev Commons Concurrent, the size of the thread pool should be set up reasonably according to actual needs and system resources.If the thread pool is too small, it may lead to the backlog of the task and affect the response ability of the system; while the thread pool is too large, it may occupy too much system resources.It is recommended to perform performance testing and tuning according to the actual situation to find a reasonable thread pool size.
The following is a sample code that sets the thread pool size according to the CPU core number:
int numberOfCores = Runtime.getRuntime().availableProcessors();
ThreadPoolExecutor executor = new ThreadPoolExecutor(numberOfCores, numberOfCores, 0L, TimeUnit.MILLISECONDS, new LinkedBlockingQueue<>());
2. Carefully select the thread pool type: ChillDev Commons Concurrent provides multiple thread pool types for options, including FIXEDTHREADPOOL, CacheDthreadPool, and WorkstealingPool.When selecting the type of the thread pool, weighing the characteristics and requirements of the task.If the task is a dense computing task, you can choose FIXEDTHREADPOOL; if the task is IO densely, you can choose cacheDthreadPool; if you need higher throughput and parallelism, you can choose WorkStealingPool.
The following is a sample code using FixedThreadPool:
int numberOfThreads = 10;
ExecutorService executor = ChillDevExecutors.newFixedThreadPool(numberOfThreads);
executor.submit(() -> System.out.println("Hello, World!"));
executor.shutdown();
3. Close the thread pool elegantly: After the use of the thread pool, it is necessary to close it in time to release the system resources.For the thread pool in ChillDev Commons Concurrent, you can use the `Shutdown ()" method to close the thread pool.However, note that calling this method back thread pool will no longer accept new tasks, but it will wait for all the submitted tasks to be completed.If you want to close the thread pool immediately, you can use the method of `shutdownnow ().
The following is a sample code for elegant closing thread pool:
executor.shutdown();
try {
if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {
executor.shutdownNow();
if (!executor.awaitTermination(60, TimeUnit.SECONDS)) {
System.err.println ("The thread pool failed to close");
}
}
} catch (InterruptedException e) {
executor.shutdownNow();
Thread.currentThread().interrupt();
}
4. Reasonably handle task execution abnormality: When using a thread pool to perform tasks, abnormalities may occur, such as the task throwing out unsatisfactory abnormalities or cancellation.When using the thread pool of ChillDev Commons Concurrent, you can use the `Future` object to obtain the execution results of the task and deal with possible abnormalities.You can use the `ISDONE ()" method to check whether the task is completed, and use the `Get ()` method to obtain the execution results of the task.If the task execution is abnormal, you can throw out the `EXECUTIONEEPTION`` Get () `method.
Here are a sample code that uses the `Future` to process tasks:
Future<Integer> future = executor.submit(() -> {
// Execute the task
return 42;
});
try {
Integer result = future.get();
System.out.println ("Task execution results:" + Result);
} catch (InterruptedException | ExecutionException e) {
// Processing task execution abnormalities
e.printStackTrace();
}
in conclusion:
The thread pool in the ChillDev Commons Concurrent Library provides a simplified and enhanced concurrent programming function, but during use, you need to pay attention to reasonable setting of thread pool size, selected thread pool type, elegantly close the thread pool, and reasonably handle task executionabnormal.By following these precautions, we can better use the thread pool to improve the concurrent performance and stability of the program.
