BlockingQueue put() method in Java with examples
The put(E e) method of BlockingQueue interface inserts element passed as parameter to method at the tail of this BlockingQueue, if queue is not full. If the queue is full, then this method will wait for space to become available and after space is available, it inserts the element to BlockingQueue.
Syntax:
public void put(E e) throws InterruptedException
Parameter: This method takes a mandatory parameter e which is the element to be inserted in LinkedBlockingQueue.
Return Value: The method does not return anything.
Exception: This method throws following exceptions:
- InterruptedException– when interruption occurred at time of waiting for queue to become available
- NullPointerException– if the element passed to method is null
Note: The put() method of BlockingQueue has been inherited from the Queue class in Java.
Below programs illustrates put(E e) method of BlockingQueue class:
Program 1:
Java
// Java Program Demonstrate put(E e) // 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); } } |
Items in Queue are [Karan, Suraj, Harsh, Rahul]
Program 2:
Java
// Java Program Demonstrate put() // method of BlockingQueue import java.util.Iterator; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.BlockingQueue; public class GFG { public void PutDemo() throws InterruptedException { // define capacity of BlockingQueue int capacityOfQueue = 5 ; // create object of BlockingQueue BlockingQueue<Employee> BQ = new LinkedBlockingQueue<Employee>(capacityOfQueue); // Add element to BlockingQueue 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); System.out.println( "Details of Employees:" ); // print details of BQ Iterator 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.PutDemo(); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } |
Details of Employees: 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]
Program 3:
Java
// Java Program Demonstrate put(E e) // 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); // try to put null value in put method try { BQ.put( null ); } catch (Exception e) { // print error details System.out.println( "Exception: " + e); } } } |
Exception: java.lang.NullPointerException
Reference: https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/BlockingQueue.html#put(E)