Java ThreadGroup activeCount()用法及代碼示例

ThreadGroup 類的 activeCount() 方法用於返回當前線程的線程組中的活動線程數。返回值隻是一個估計值，因為在此方法遍曆內部數據結構時，線程數可能會動態變化。

用法

public static int activeCount()

它返回當前線程的線程組中的活動線程數。

示例

class NewThread extends Thread 
{
    NewThread(String threadname, ThreadGroup tg)
    {
        super(tg, threadname);
    }
    public void run()
    {
        for (int i = 0; i < 10; i++) 
        {
            try
            {
                Thread.sleep(10);
            }
            catch (InterruptedException ex) 
            {
              System.out.println(Thread.currentThread().getName() + " interrupted");
            }
        }
        System.out.println(Thread.currentThread().getName() + " completed executing");
    }
} 
public class ThreadGroupActiveCountExp
{
    public static void main(String arg[])
    {
        // creating the thread group
        ThreadGroup tg1 = new ThreadGroup("parent thread group");

        // creating the threads
        NewThread t1 = new NewThread("Thread-1", tg1);
        NewThread t2 = new NewThread("Thread-2", tg1);
        NewThread t3 = new NewThread("Thread-3", tg1);
        
        // this will call the run() method
        t1.start();
        t2.start();
        t3.start();

        // checking the number of active thread
        System.out.println("Number of active thread:"+ tg1.activeCount());
    }
}

輸出：

Number of active thread:3
Thread-1 completed executing
Thread-2 completed executing
Thread-3 completed executing

相關用法

注：本文由純淨天空篩選整理自 Java ThreadGroup activeCount() method。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。