javaSetter
Platform and version requirements: JVM (1.0) 
val KMutableProperty<*>.javaSetter: Method?
Returns a Java Method instance corresponding to the setter of the given mutable property, or null if the property has no setter, for example in case of a simple private var in a class.
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Licensed under the Apache License, Version 2.0.
    https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.reflect.jvm/java-setter.html