极客教程Java BlockingQueue remove()方法及示例
BlockingQueue 的 remove(Object obj) 方法只从这个BlockingQueue中移除一个作为参数传递的给定对象的实例，如果它存在的话。如果这个队列包含一个或多个元素e的实例，它将删除一个元素e，即obj.eals(e)，如果这个队列包含现在从BlockingQueue中删除的元素，该方法将返回true。
语法
public boolean remove(Object o)
参数： 该方法接受一个强制性参数obj，它是要从BlockingQueue中移除的元素。
返回值： 如果该队列包含现在从BlockingQueue中移除的元素，该方法返回true。如果BlockingQueue不包含obj 这个元素，那么这个方法返回false。
注意 ： BlockingQueue 的 remove() 方法已经从Java的 Queue 类中继承了。
下面的程序说明了BlockingQueue类的remove(Object obj)方法。
程序1:
// Java Program Demonstrate remove(Object obj)
// method of BlockingQueue
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.BlockingQueue;
public class GFG {
public static void main(String[] args)
throws InterruptedException
{
// define capacity of BlockingQueue
int capacityOfQueue = 4;
// create object of BlockingQueue
BlockingQueue<String> BQ
= new LinkedBlockingQueue<String>(capacityOfQueue);
// Add element using put() method
BQ.put("Karan");
BQ.put("Suraj");
BQ.put("Harsh");
BQ.put("Rahul");
// print elements of queue
System.out.println("Items in Queue are " + BQ);
// try to remove Karan from Queue using remove()
boolean try1 = BQ.remove("Karan");
// Print result of remove()
System.out.println("String name Karan is removed :"
+ try1);
// try to remove Sunny from Queue using remove()
boolean try2 = BQ.remove("Sunny");
// Print result of remove()
System.out.println("String name Sunny is removed :"
+ try2);
// try to remove Sunny from Queue using remove()
boolean try3 = BQ.remove("Harsh");
// Print result of remove()
System.out.println("String name Harsh is removed :"
+ try2);
// print queue
System.out.println("After Removing Some Elements:");
System.out.println("Items in Queue are " + BQ);
}
}
输出。
Items in Queue are [Karan, Suraj, Harsh, Rahul]
String name Karan is removed :true
String name Sunny is removed :false
String name Harsh is removed :false
After Removing Some Elements:
Items in Queue are [Suraj, Rahul]
计划1。
// Java Program Demonstrate remove(object obj)
// method of BlockingQueue
import java.util.Iterator;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.BlockingQueue;
public class GFG {
public void removeDemo() throws InterruptedException
{
// define capacity of BlockingQueue
int capacityOfQueue = 5;
// create object of BlockingQueue
BlockingQueue<Employee> BQ
= new LinkedBlockingQueue<Employee>(capacityOfQueue);
// Add element to LinkedBlockingQueue
Employee emp1 = new Employee("Ranjeet", "Tester", "29000", 27);
Employee emp2 = new Employee("Sanjeet", "Manager", "98000", 34);
Employee emp3 = new Employee("Karan", "Analyst", "44000", 30);
// Add Employee Objects to BQ Using put(E e)
BQ.put(emp1);
BQ.put(emp2);
BQ.put(emp3);
// print details of BQ
System.out.println("Before removing Elements");
Iterator itr = BQ.iterator();
while (itr.hasNext())
System.out.println(itr.next());
// remove employee2 name Sanjeet from BQ
// Using remove(Object obj) method
BQ.remove(emp2);
// Also remove Ranjeet employee1 from BQ
// Using remove(Object obj) method
BQ.remove(emp1);
// print details of BQ
System.out.println("After removing Some Elements");
itr = BQ.iterator();
while (itr.hasNext())
System.out.println(itr.next());
}
// create an Employee Object with name,
// position, salary and age as attributes
public class Employee {
public String name;
public String position;
public String salary;
public int Age;
Employee(String name, String position,
String salary, int age)
{
this.name = name;
this.position = position;
this.salary = salary;
this.Age = age;
}
@Override
public String toString()
{
return "Employee [name=" + name + ", position="
+ position + ", salary=" + salary + ", Age=" + Age + "]";
}
}
// Main Method
public static void main(String[] args)
{
GFG gfg = new GFG();
try {
gfg.removeDemo();
}
catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
输出。
Before removing Elements
Employee [name=Ranjeet, position=Tester, salary=29000, Age=27]
Employee [name=Sanjeet, position=Manager, salary=98000, Age=34]
Employee [name=Karan, position=Analyst, salary=44000, Age=30]
After removing Some Elements
Employee [name=Karan, position=Analyst, salary=44000, Age=30]
**参考资料: ** https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/BlockingQueue.html#remove(java.lang.Object)