Java Tutorials and Best Practices
Managing the configuration of microservices in a distributed system has been a tedious and time-consuming task especially if we’re talking about huge systems which consist of considerable amount of microservices. Each time you need to change the configuration of a microservice, you would go to the corresponding project, change its configuration and then restart the application for the change to...
In this tutorial we show how Spring Boot serves static resources like (html, js, css) in a web application. 1- Default path for static resources By default Spring Boot serves static resources defined under the following paths: /META-INF/resources/ /resources/ /static/ /public/ Except for index.html which is served as the root resource when accessing the root URL of a Spring Boot application,...
#Problem When redirecting back to your application after a successful OAuth2 authentication, the following error occurs: #Solution This error occurs when the redirect URL set under the authorization service(Google, Facebook … etc) is not defined as a permitted URL inside your application. The permitted URL is the one which can be accessed without authentication. When the authorization service redirects to...
#Problem When trying to authenticate a user using OAuth2 through a third-party service like (Google, Facebook .. etc.), the following error occurs: #Solution redirect_uri_mismatch error occurs when the redirect URL defined for your application at the authorization service doesn’t match with the value of parameter “redirect_uri” passed by your request. When integrating OAuth2 with Spring Boot, the default value of redirect_uri...
In this tutorial we explain how to secure a Spring Boot application using OAuth2. If you follow the steps in order, you’ll get a fully working secured application which authenticates user requests through Google API. Prerequisites: Eclipse IDE (neon release) Maven 4 Java 1.8 Spring Boot 2.0.0 1- Create maven project Open eclipse then create a new maven project and...
Sometimes when trying to consume a web service from a java client, you get a 403 forbidden HTTP response code, even though the service is accessible normally from web browsers. The HTTP 403 forbidden error doesn’t necessarily occur due to missing authentication attributes, some web services would only authorize web browsers or some specific clients to access them, while they...
By default, filters doesn’t support excluding a specific URL pattern, whenever you define a URL pattern for a filter then any request matching this pattern is handled by the filter without exceptions. The simplest way for excluding URLs from a filter is to map your filter to a very specific pattern. This is feasible when done in early development stages,...
In this tutorial we show how to create a Spring Boot application that communicates with an Oracle data source through Hibernate. Prerequisites: Eclipse IDE (neon release) Maven 4 Java 1.8 1- Create maven project Open eclipse, then create a new maven project and name it as SpringBootHibernate. At the end of this tutorial, we’ll get the following project structure: 2-...
By default, Spring Boot applications run on an embedded Tomcat via port 8080. In order to change the default port, you just need to modify server.port attribute which is automatically read at runtime by Spring Boot applications. In this tutorial, we provide the common ways of modifying server.port attribute. 1- application.properties Create application.properties file under src/main/resources and define server.port attribute...
This tutorial provides a step-by-step guide on how to build a restfull web service using Spring Boot. Prerequisites: Eclipse IDE (neon release) Maven 4 Java 1.8 1. Create maven web project Open eclipse then create a new maven web project and name it as SpringBootRest. The structure of the generated project looks like the following: 2. pom.xml After creating the web project, the...