Java DelayQueue clear()用法及代碼示例

Java中的DelayQueue的clear()方法用於刪除當前DelayQueue對象中的所有元素。返回此調用後，隊列將為空。延遲中沒有過期的隊列中的元素會自動從隊列中丟棄。

句法：

public void clear()

參數：此方法不帶任何參數。

返回值：此方法不返回任何值。

以下示例程序旨在說明上述方法：

// Java program to illustrate the clear() method 
// of DelayQueue class 
  
import java.util.concurrent.DelayQueue; 
import java.util.concurrent.Delayed; 
import java.util.concurrent.TimeUnit; 
  
public class GFG { 
    public static void main(String args[]) 
    { 
        // Create a DelayQueue instance 
        DelayQueue<Delayed> queue = new DelayQueue<Delayed>(); 
  
        // Create an Object of type Delayed 
        Delayed obj = new Delayed() { 
            public long getDelay(TimeUnit unit) 
            { 
                return 24; // some value is returned 
            } 
  
            public int compareTo(Delayed o) 
            { 
                if (o.getDelay(TimeUnit.DAYS) >  
                                  this.getDelay(TimeUnit.DAYS)) 
                    return 1; 
                else if (o.getDelay(TimeUnit.DAYS) ==  
                                  this.getDelay(TimeUnit.DAYS)) 
                    return 0; 
                return -1; 
            } 
        }; 
  
        // Add the obj to the queue 
        queue.add(obj); 
  
        // Check if queue is empty 
        System.out.println("Is queue empty() : "
                           + queue.isEmpty()); 
  
        // Remove all elements from queue 
        // uing clear() method 
        queue.clear(); 
  
        // Check if queue is empty 
        System.out.println("Is queue empty after calling clear() : "
                           + queue.isEmpty()); 
    } 
}

輸出：

Is queue empty() : false
Is queue empty after calling clear() : true

相關用法

注：本文由純淨天空篩選整理自psil123大神的英文原創作品 DelayQueue clear() method in Java。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。