定義一個Java的interface：

public interface IJavaTest {
void test(int param);
    void test(Integer param);
    void test(float param);
    void test(Float param);
}

用Kotlin實現這個Java interface，用AS的自動匯入如下：

class KotlinTest : IJavaTest {
override fun test(param: Int) {
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
 
}
override fun test(param: Int?) {
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
}
override fun test(param: Float) {
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
}
override fun test(param: Float?) {
 
TODO("not implemented") //To change body of created functions use File | Settings | File Templates.
}
}

Java把基本資料型別和包裝類引數定義看做是方法過載，而Kotlin認為這兩個Java方法是一樣的。