HTTP cache with Spring examples

Caching is a powerful feature of the HTTP protocol but for some reason, it’s mainly considered for static resources like images, CSS stylesheets, or JavaScript files. However, HTTP caching isn’t limited to application’s assets as you can also use it for dynamically computed resources.

With a small amount of work, you can speed up your application and improve the overall user experience. In this article, you will learn how to use the built-in HTTP response cache mechanism for Spring controller’s results.

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How to bind @RequestParam to object in Spring

Do you have multiple parameters annotated with @RequestParam in a request mapping method and feel it isn’t readable?

The annotation looks pretty straightforward when there’s one or two input parameters expected in a request but when the list gets longer you might feel overwhelmed.

You cannot use the @RequestParam annotation inside objects but it doesn’t mean you’re left with no other solution. In this post, I’m going to show you how to replace multiple @RequestParams with an object.

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Feature toggle in Spring Boot 2

Whether you like it or not, software development is a collaborative activity. Integration work has always been demonized and treated as necessary evil. There are several approaches which try to solve the challenge of effective integration. The feature toggle belongs to that group. In this article, you’ll see in practice how feature toggles, also known as feature flags, can be used in your Spring Boot application.

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Sending HTML email with Spring Boot and Thymeleaf

Sending an email from the backend application part is a quite common use case in the world of enterprise applications. Although HTML content isn’t standardized message format, numerous mail clients support at least a subset of the markup language. In this post you will learn how to send an HTML email using Spring Boot standard modules and prepare an HTML content for a message using Thymeleaf template engine.

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Custom validation annotation in Spring

Although built-in validation support in Spring is largely sufficient for standard use cases, sooner or later you will run into a situation when the sets of validation annotations provided by JSR 303 or Hibernate Validator aren’t enough. In this post you will learn how to create a simple constraint annotation served by a custom validator with access to the Spring context of a Spring Boot application.

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Faster Spring Boot startup

As software developers, we always look for opportunities to improve our efficiency at work and optimize repeatable activities. One of them is application startup. Even if you cover your production code with unit tests and follow TDD, from time to time checking how the whole application works is inevitable. The more often you run it, the more time is wasted on waiting until the application is ready to operate.

Although the fast restart provided by Spring Boot DevTools is helpful for library class loading, it doesn’t solve the issue with the long startup of your own application code. From this post you will learn how to decrease the total number of coffee breaks in daily work by configuring faster Spring Boot startup in your local development environment.

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Multiple TTL caches in Spring Boot

Spring Framework provides a comprehensive abstraction for common caching scenarios without coupling to any of supported cache implementations. However, declaration of expiration time for a particular storage is not a part of this abstraction. If we want to set Time To Live of a cache, the configuration of the chosen cache provider must be tuned. From this post you will learn how to prepare setup for several Caffeine caches with different TTL configurations.

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Spring Boot properties per Maven profile

In the previous post you could read about separate Spring Boot builds for a local development machine and public environments. It’s highly possible that in addition to such setup you would like to load different Spring properties files based on the active Maven profile. In this note you will learn how to accomplish the desired result in a few easy steps.

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Dual jar/war build for Spring Boot

The great thing about Spring Boot is no need for an external servlet container. All that is needed reside inside a single runnable JAR file. In a very few steps, development of a new application can be started without installation or configuration of any additional software.

Yet, sometimes you might want to deploy your application to some server as a regular WAR file. For instance, you convert an existing application and want to keep your continuous delivery pipe untouched or a particular container is enforced by a company’s policy. The reason for building a WAR file may vary across teams, but for development purpose a simple executable JAR file with an embedded server might be preferable.

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