Search results for: Open API

In the previous tutorial, we learned that how we can do User Authentication with Amazon Cognito in Spring Boot Application. In this tutorial, we will take our previous learnings and continue with the following. Create Rest Controller to handle /login HTTP POST requests. Read username and password from the request body to authenticate with Amazon Cognito…

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To schedule a task in Spring Boot we use the @Scheduled annotation.  We place the @Scheduled annotation above the declaration of the method that should not expect any parameters, and the return type should be void.  Spring Boot internally uses the TaskScheduler interface to schedule the annotated execution methods. Schedule a task in Spring Boot – steps…

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In this tutorial, you will learn to design and deploy the multi-container based Spring Boot application using Docker compose. To learn more about Docker, please check Docker Tutorials page. Overview In the previous tutorial, we learned how to Dockerize a simple Spring Boot-based application. As it was a small application we have handled each container…

Read More Docker Compose: Deploying Spring Boot Microservices

some data in a file import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.core.io.ClassPathResource; import org.springframework.core.io.Resource; import org.springframework.util.FileCopyUtils; import java.io.*; import java.nio.charset.StandardCharsets; @SpringBootApplication public class DemoApplication { public static void main(String[] args) throws IOException { SpringApplication.run(DemoApplication.class, args); readFile(); } public static void readFile() throws IOException { // read a file Resource resource = new ClassPathResource(“classpath:data.txt”); // get inputStream…

Read More Read a File From the Resources Folder in Spring Boot

In this tutorial, you will learn to design and run in a Docker container a simple Spring Boot application that uses MongoDB. To learn more about Docker, please check Docker Tutorials page. Overview Docker is becoming an increasingly important tool in the DevOps process.  It allows you to package an application, along with all its…

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In this tutorial, we are going to see how to create a simple Spring Boot project containing a handler that takes the name of the user as a parameter and returns a welcome message. We are then going to deploy it as a serverless application on AWS Lambda and test it. The first step is…

Read More AWS Lambda with Spring Boot – A Simple GreetMe Example

Spring Boot is a popular framework for building Java-based web applications. It provides a simple and efficient way to build, deploy and run Java applications quickly. In this tutorial, we’ll explore the framework’s basics, including its features, advantages over the Spring Framework, and how to get started with creating your first application using it. Whether…

Read More Spring Boot: Getting Started Guide

In this tutorial, we are going to see how we can throw custom exceptions with a custom payload in a Spring Boot application and deploy it on AWS as a serverless Lambda function. Let us start by creating a simple Spring boot project. In this project, we are going to create a Request Handler that…

Read More Handle Custom JAVA Exceptions in AWS Lambda with Spring Boot

class CheckIfArrayContainsValue { public static void main(String[] args) { String[] programmingLanguages = {“Python”, “Kotlin”, “Ruby”, “JavaScript”, “C#”, “Java”, “Flutter”}; for (String lang : programmingLanguages) { if (lang.equals(“Java”)) { System.out.println(“It does contain!”); break; // value found, exit the loop } } } } Output: It does contain!   Here, we are iterating over the array, and…

Read More Check if Array Contains a Value in Java

Output: Some String   Here, we put the creation of the Scanner object into a try-with-resources because we want to close the Scanner after it reads all the data. We passed the “\\A” to tell the Scanner to read the entire input stream. import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.nio.charset.StandardCharsets; class ConvertInputStreamToString { /** *…

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In this tutorial, we will explore different methods to find duplicate elements in a Java array, including using nested loops, sets, streams, and hash tables. We will also discuss the time and space complexity of each method, so you can choose the most efficient one for your specific use case. Whether you’re a beginner or…

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class EscapeDoubleQuotesInString { public static void main(String[] args) { String str = “Hello, I’m \”Steve\” and I am \”Java\” developer”; System.out.println(str); } } Output: Hello, I’m “Steve” and I am “Java” developer Escape double quotes in a JSON object in Java There are many cases where you might need to escape double quotes. In this…

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Internationalization (i18n) is the process of making your application and services capable of delivering in different languages. This tutorial will show how the Spring Boot framework manages internationalization. Overview The internet has become global, implying that any application or website can target millions of users worldwide. Although half of the world’s population may have access…

Read More Spring MVC Internationalization Tutorial