How to use size() in android PriorityBlockingQueue?

AndroidMobile DevelopmentApps/Applications

Before getting into the example, we should know what PriorityBlockingQueue is. It is an unbounded queue and follows the same order as a priority queue. The main usage of priority blocking queue is, it going to handle out of memory error.

This example demonstrates about How to use size() in android PriorityBlockingQueue

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version = "1.0" encoding = "utf-8"?>
<LinearLayout xmlns:android = ""
   xmlns:app = ""
   xmlns:tools = ""
   android:layout_width = "match_parent"
   android:gravity = "center"
   android:layout_height = "match_parent"
   tools:context = ".MainActivity"
   android:orientation = "vertical">
      android:id = "@+id/actionEvent"
      android:textSize = "40sp"
      android:layout_marginTop = "30dp"
      android:layout_width = "wrap_content"
      android:layout_height = "match_parent" />

In the above code, we have taken a text view to show PriorityBlockingQueue elements.

Step 3 − Add the following code to src/

package com.example.myapplication;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import java.util.concurrent.PriorityBlockingQueue;
public class MainActivity extends AppCompatActivity {
   PriorityBlockingQueue priorityBlockingQueue;
   @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
   protected void onCreate(Bundle savedInstanceState) {
      priorityBlockingQueue = new PriorityBlockingQueue();
      final TextView actionEvent = findViewById(;
      actionEvent.setText("" + priorityBlockingQueue);
      actionEvent.setOnClickListener(new View.OnClickListener() {
         public void onClick(View v) {
            actionEvent.setText("" + priorityBlockingQueue.size());

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen –

Now click on text view to show the result as shown below –

Click here to download the project code

Published on 10-Apr-2019 07:52:22