Why is this an issue?

Duplicated string literals make the process of refactoring complex and error-prone, as any change would need to be propagated on all occurrences.

Exceptions

To prevent generating some false-positives, literals having 5 or less characters are excluded as well as literals containing only letters, digits and '_'.

How to fix it

Instead, use constants to replace the duplicated string literals. Constants can be referenced from many places, but only need to be updated in a single place.

Code examples

Noncompliant code example

With the default threshold of 3:

class A {
    fun run() {
        prepare("string literal")    // Noncompliant - "string literal" is duplicated 3 times
        execute("string literal")
        release("string literal")
    }

    fun method() {
        println("'")                 // Compliant - literal "'" has less than 5 characters and is excluded
        println("'")
        println("'")
    }
}

Compliant solution

class A {
    companion object {
        const val CONSTANT = "string literal"
    }

    fun run() {
        prepare(CONSTANT)    // Compliant
        execute(CONSTANT)
        release(CONSTANT)
    }
}