In this tutorial, we’ll implement a RestTemplate Error Handling Example. But before moving ahead, let’s see why is there a need to do this? The answer is: It becomes very tedious to handle exceptions through try/catch blocks as applications scale. An Efficient way to avoid this hassle is to implement a reusable error handler that…
Read More RestTemplate Error Handling ExampleThis tutorial will teach you how to leverage RestTemplate to access RESTful APIs protected by basic authentication. You will learn to create a Basic Authentication-secured REST API and access it via RestTemplate. What is Basic Authentication As the name suggests, it is a basic form of authentication in which we must provide the correct username…
Read More RestTemplate Example with Basic AuthenticationIn this tutorial, we’ll learn what IoC (Inversion of Control) and DI (Dependency Injection) are, as well as take a look at how these are implemented in the Spring framework. What Is Inversion of Control (IoC)? Inversion of Control is a principle in software engineering that separates the control of objects or how parts of…
Read More Dependency Injection and Inversion of Control in SpringWhen developing Spring Boot applications, we need to tell the Spring Framework where to look for the custom code that we wrote. Using component scan is one method of asking Spring to detect the components of our application which Spring will then manage for us from Initialization to Execution. Spring needs the information to locate…
Read More Component Scanning in a Spring Boot ApplicationIn this tutorial, you will learn how to define custom filters and specify their order of invocation in the Spring Boot application. What is a custom filter? Filters enable us to filter on either the request to a resource, the response from a resource, or both. Spring Boot provides a few options to register custom…
Read More How to Define Custom Filters in Spring BootIn this tutorial, you will learn how to use TestRestTemplate to get a list of objects. If you are also interested to learn how to send an HTTP POST request, then please have a look at the “TestRestTemplate HTTP Post Example” tutorial. Maven Dependency To use TestRestTemplate in your Spring Boot project, you should have the…
Read More Get List of Objects with TestRestTemplateThis tutorial will teach you how to use TestRestTemplate to send HTTP Post requests. If you are also interested to learn how to send an HTTP GET request, then please have a look at the “Get List of Objects with TestRestTemplate” tutorial. What is TestRestTemplate? TestRestTemplate is HTTP Client that you use for Spring Boot…
Read More TestRestTemplate HTTP Post ExampleIn this tutorial, you will learn how to get the port number on which your Spring Boot application is running. Whether it is a defined port number or a random port number. Let’s start learning how to get the running port number first. @LocalServerPort Annotation If your Spring Boot application is configured to start on…
Read More Get the Random Port Number in Spring BootIn this tutorial, you will learn about @SpringBootTest annotation. You will use this annotation to write Integration Tests for your Spring Boot application. @SpringBootTest annotation is used to create a Spring Application Context that will be used during the test. It will make Spring Framework scan your application classes and look for different annotations. Depending…
Read More @SpringBootTest Annotation ExampleThis tutorial will teach you how to migrate from the depricated WebSecurityConfigurerAdapter towards the content-based security configuration. Spring Security allowed customizing HTTP security by extending a WebSecurityConfigurerAdapter class. This customization included user authorization, user authentication, etc. But in Spring Security 5.7.0-M2 the WebSecurityConfigurerAdapter is deprecated. This is because Spring Framework developers encourage users to move…
Read More Migrate from Deprecated WebSecurityConfigurerAdapter (Solved!)import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.scheduling.annotation.EnableScheduling; @EnableScheduling @SpringBootApplication public class ScheduledDemoApplication { public static void main(String[] args) { SpringApplication.run(ScheduledDemoApplication.class, args); } } import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Component; @Component public class ScheduledTaskService { @Scheduled(fixedRate = 5000) public void execute() { // some logic that will be executed on a schedule System.out.println(“Code is being executed…”); } } Output:…
Read More How to Schedule a Task in Spring Bootsome 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 BootIn this tutorial, you will learn to design and deploy the simple Spring Boot-based application to Docker. Overview Docker is becoming an increasingly important tool in the DevOps process. It allows you to package an application, along with all its dependencies into a so-called container, and then run it in any environment. We will see…
Read More Deploying Spring Boot + MongoDB Application with DockerIn this tutorial, you will learn how to use Jackson ObjectMapper with Spring Boot application to serialize and deserialize Java objects. Overview In today’s time, the JSON format is one of the most popular formats to transfer and exchange data on the world wide web. Almost all RESTful web services support JSON as input and output…
Read More Jackson ObjectMapper TutorialIn this tutorial, you will learn how to create a custom password encoder in a Spring Boot application that uses Spring Security. Table of contents Create a Spring Boot project and add database connection properties. Add a User model. Create a User repository. Implement a custom PasswordEncoder. Create a service class that implements UserDetailService Add…
Read More Custom Password Encoder in Spring Security