Kotlin Language Features Related to Null Handling

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Any software engineer with a Java background would find the null handling features in the Kotlin language interesting. Let's summarize this topic with some examples. Nullable types: In Kotlin, types are non-nullable by default. If you want a variable to be able to hold a null value, you need to explicitly declare its type as nullable using the Type? syntax. For example, String? denotes a nullable string, while String represents a non-nullable string. Safe calls (?.): Kotlin introduces the safe call operator (?.) for handling nullable types. It allows you to safely invoke a method or access a property on a nullable object. If the object is null, the expression returns null instead of throwing a NullPointerException. Example: data class Person(val name: String, val age: Int, val address: String?) fun main() {     // Create a person with a nullable address     val person1 = Person("John Doe", 25, "123 Main Street")     val person2 = Person("Jane Doe", 30,...
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DEVOPS

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This table shows imporant aspects of DEVOPS and related software products. The ones that I have used in the past are painted in red. I think this is a very nice table to look at alternative solutions to use for new projects. Of course some of them are essential:

  • Version control. (Subversion,  Git, ..)
  • Build tool. (Maven, Gradle, ..)
  • Testing. Unit Test, Stress Test, UI TEst. (JUnit, JMeter, Selenium)
  • Continuous Integration. (Bamboo, Continuum, ..)

 The others seem to depend on the size of the organization and the project. Some use AWS, others manage their own servers. 

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