java 執行緒池執行緒忙碌且阻塞佇列也滿了時給一個拒接的詳細報告

執行緒池執行緒忙碌且阻塞佇列也滿了時給一個拒接的詳細報告。下面是一個自定義的終止策略類，繼承了ThreadPoolExecutor.AbortPolicy類並覆蓋了rejectedExecution方法把當前執行緒及執行緒池的狀態給做了一個詳細的報告。

預設丟擲的異常訊息比較簡單：

        /**
         * Always throws RejectedExecutionException.
         *
         * @param r the runnable task requested to be executed
         * @param e the executor attempting to execute this task
         * @throws RejectedExecutionException always
         */
        public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {
            throw new RejectedExecutionException("Task " + r.toString() +
                                                 " rejected from " +
                                                 e.toString());
        }

下面是詳細報告的程式碼：

public class AbortPolicyWithReport extends ThreadPoolExecutor.AbortPolicy {
    
    protected static final Logger logger = LoggerFactory.getLogger(AbortPolicyWithReport.class);
    
    private final String threadName;
    
    private final URL url;
    
    public AbortPolicyWithReport(String threadName, URL url) {
        this.threadName = threadName;
        this.url = url;
    }
    
    @Override
    public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {
        String msg = String.format("Provider端執行緒池滿!" +
                " Thread Name: %s, Pool Size: %d (active: %d, core: %d, max: %d, largest: %d), Task: %d (completed: %d)," +
                " Executor status:(isShutdown:%s, isTerminated:%s, isTerminating:%s), in %s://%s:%d!" ,
                threadName, e.getPoolSize(), e.getActiveCount(), e.getCorePoolSize(), e.getMaximumPoolSize(), e.getLargestPoolSize(),
                e.getTaskCount(), e.getCompletedTaskCount(), e.isShutdown(), e.isTerminated(), e.isTerminating(),
                url.getProtocol(), url.getIp(), url.getPort());
        logger.warn(msg);
        throw new RejectedExecutionException(msg);
    }

}