Accessing Kotlin extension functions from Java

Question

Is it possible to access extension functions from Java code?

I defined the extension function in a Kotlin file.

package com.test.extensions

import c         


        

Answer 1

You need to duplicate your functions in the class files:

Create Kotlin file , for ex Utils.kt

Enter the code

  class Utils {
                companion object {
                    @JvmStatic
                    fun String.getLength(): Int {//duplicate of func for java
                        return this.length
                    }
                }
            }

        fun String.getLength(): Int {//kotlin extension function
            return this.length
        }

OR

class Utils {
    companion object {

        @JvmStatic
        fun getLength(s: String): Int {//init func for java
            return s.length
        }
    }
}

fun String.getLength(): Int {//kotlin extension function
    return Utils.Companion.getLength(this)//calling java extension function in Companion
}

In kotlin use:

val str = ""
val lenth = str.getLength()

In Java use this:

String str = "";
 Integer lenth = Utils.getLength(str);