I have this kind of implementation but it’s not allowed after bumping Kotlin to 1.6.10 and received ...

# random

[samp]

I have this kind of implementation but it’s not allowed after bumping Kotlin to 1.6.10 and received the following error which was warning until previous version.

Code:

sealed class PowerTool(
    @JvmField open val name: String,
    @JvmField open val price: Double
) {
    data class CircularSaw(
        val diameter: Int,
        val cordless: Boolean,
        override val name: String,
        override val price: Double
    ) : PowerTool(name, price)

    data class DrillPress(
        val rpm: Int,
        override val name: String,
        override val price: Double
    ) : PowerTool(name, price)
}

Error: JvmField can only be applied to final property

My requirement for jvm field is: I need @JvmField for java consumers as I don’t want to refactor the code to use the setter/getter method and want to use as a field.

Any thoughts?

[Brett McGinnis]

Untitled.kt

Untitled.kt

[louiscad]

You need to no longer make it open, which means removing the data modifier, and removing the `override val`s.

[samp]

@louiscad: open i added so i can override them in the subclasses that was the purpose.
and i don’t want to do the whole java refactor (for java consumers) so i have added jvm field.
Are you suggesting to remove data modifier and remove override val and use a different name for it?

[samp]

@Brett McGinnis: in the second solution, my java consumers won’t be happy and they need to refactor the code

[ephemient]

overrideable @JvmField shouldn't have been allowed in the first place, it leads to broken code generation elsewhere in the compiler

[ephemient]

I believe that louiscad is suggesting this

sealed class PowerTool(
    @JvmField val name: String,
    @JvmField val price: Double
) {
    class CircularSaw(
        val diameter: Int,
        val cordless: Boolean,
        name: String,
        price: Double
    ) : PowerTool(name, price)

    class DrillPress(
        val rpm: Int,
        name: String,
        price: Double
    ) : PowerTool(name, price)
}

[samp]

hmm, in this case i need to implement toString hashCode and all.
would it work for when expression?

[ephemient]

yes

[louiscad]

The IDE can generate these

[samp]

yes, IDE generate them but those are basic methods which are generated by IDE.
I don’t think so that would work correctly.
for eg: like this

override fun equals(other: Any?): Boolean {
            if (this === other) return true
            if (javaClass != other?.javaClass) return false
            return true
        }

        override fun hashCode(): Int {
            return javaClass.hashCode()
        }