How to auto call function in Kotlin for every function call within a class

Question

I have a class with multiple functions

class Foo() {
    fun one() {
        //do something
    }

    fun two() {
        // do something
    }

    fun three() {
        // do something
    }
}

How can I trigger a call to a Logger object that I have, so that in the logs I can see all functions accessed or called, without explicitly placing the log call on every function to keep the code clean. I'm trying to keep a full log trace of all functions called within a service api call, but I don't want to have something like this

class Foo() {
    fun one() {
        log.call()
        //do something
    }

    fun two() {
        log.call()
        // do something
    }

    fun three() {
        log.call()
        // do something
    }
}

Technically, you can, using a compiler plugin, but they are very little documented and complex to write. — Alexey Romanov, Jul 17 '19 at 07:26

score 2 · Answer 1 · answered Jul 17 '19 at 08:08

2

You can't do it in plain Kotlin. But this is exactly the sort of thing Aspect-Oriented Programming was intended for.

I haven't used it myself, but if you want to do it in Kotlin, you might look at Spring AOP. See also discussions here and this question.

answered Jul 17 '19 at 08:08

gidds

16,558
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Thanks I'll check those out – avillagomez Jul 17 '19 at 22:14

score 1 · Answer 2 · answered Jul 17 '19 at 22:33

1

In Java I would write an IvocationHandler to create a dynamic proxy. See this question

answered Jul 17 '19 at 22:33

Michiel Leegwater

1,172
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How to auto call function in Kotlin for every function call within a class

2 Answers2