Data Classes for Java

Re:Data Classes for Java by Naac on Wednesday November 01, 2017 @10:21PM (#15607320)

  data class Animal(dog: String, numberOfLegs: Int)

and

    Animal dog = Animal.builder()
    .setName("dog")
    .setNumberOfLegs(4)
    .build();

are very different. In this case the builder pattern is more powerful as it lets you pass around builders that haven't been "built" yet. Kind of like currying.

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Re:Data Classes for Java by dangets on Wednesday November 01, 2017 @10:27PM (#15607360)

True, but the constructor method is checked/validated at compile time vs. run time with the builder pattern. Not quite the same as your example, but Kotlin does have good syntax for copying data classes while only changing a single field - this could be used similar to your currying usage.

https://kotlinlang.org/docs/reference/data-classes.html#copy...

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Re:Data Classes for Java by guelo on Thursday November 02, 2017 @12:33AM (#15607860)

Here's that kotlin copy syntax

      val cat = dog.copy(name = "cat")

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