Posts by Riccardo Lippolis

Converting Char to Int in Kotlin

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Riccardo Lippolis

The Kotlin standard library contains a lot of helper functions on top of the Java standard library for our convenience. Some of those functions help us in converting between different data types. For example, the String.toInt() function converts a number formatted as String to its Int representation. But how do we accomplish the same with a Char? Spoiler alert: NOT by using Char.toInt()!

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Kotlin method reference to companion object function

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Riccardo Lippolis

Functions defined in Kotlin companion objects are often seen as the 'equivalent' of static methods in Java. Although there are some similarities, there are also some caveats you should be aware of. For example, how to use method references (or, to be pedantic: function references) to refer to functions defined in a companion object.

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Slim modular Java 9 runtime Docker image with Alpine Linux

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Riccardo Lippolis

With the release of Java 9, and the introduction of Project Jigsaw (the Java Platform Module System), we no longer have the need for a full-blown JRE to run our Java applications. It is now possible to construct a stripped-down Java Runtime, containing the minimum set of required modules. This allows us to create slim Docker containers without excess baggage. The source code belonging to this blog post can be found at: https://github.com/rlippolis/java9-runtime-image

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Securing your application landscape with Spring Cloud Security - Part 1

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Riccardo Lippolis

Securing an application is difficult. Securing an entire application landscape is even more difficult! In this modern era of blazing fast microservices we do not want the additional complexity of having to secure it all manually. This is where Spring Cloud Security comes in. By combining proven technologies, it helps us achieve performant, configurable end-to-end security across multiple applications. So what technologies are being combined? Well, a lot... We will not mention them all here, but the foundation relies on Spring Boot and Spring Security OAuth. OAuth, or, in our case, OAuth2 is basically an authorization delegation protocol. To quote Wikipedia, OAuth:

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