[KTLN-512] Passing a Type to Generic Method in Kotlin (#904)

* added unit tests

* code fixes

* fixed unit tests

* fixed unit tests

* fixed unit tests

Author: albertache1998

core-kotlin-modules/core-kotlin-advanced-3/src/test/kotlin/com/baeldung/passTypeToGenericMethod/PassTypeToGenericMethod.kt

@@ -0,0 +1,58 @@
+package com.baeldung.passTypeToGenericMethod
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+
+class PassTypeToGenericMethod {
+    @Test
+    fun `pass type to generic method using reified parameters`() {
+
+        assertEquals("String", passTypeUsingReifiedParameter<String>())
+        assertEquals("Int", passTypeUsingReifiedParameter<Int>())
+    }
+
+    @Test
+    fun `pass type to generic method using class parameters`() {
+
+        assertEquals("String", passTypeUsingClassParameter(String::class.java))
+        assertEquals("int", passTypeUsingClassParameter(Int::class.java))
+    }
+
+    @Test
+    fun `pass type to generic method using higher order functions`() {
+        val intValue = passTypeUsingHigherOrderFunction{42}
+        val stringValue = passTypeUsingHigherOrderFunction{"Generic Method!"}
+
+        assertEquals(42, intValue)
+        assertEquals("Generic Method!", stringValue)
+    }
+
+    @Test
+    fun `pass type to generic method using type casting`() {
+        val intValue = passTypeUsingTypeCasting(0)
+        val stringValue = passTypeUsingTypeCasting("")
+
+        assertEquals(42, intValue)
+        assertEquals("Generic Method!", stringValue)
+    }
+}
+
+inline fun <reified T> passTypeUsingReifiedParameter(): String? {
+    return T::class.simpleName
+}
+
+fun <T> passTypeUsingClassParameter(clazz: Class<T>): String {
+    return clazz.simpleName
+}
+
+fun <T> passTypeUsingTypeCasting(type: T): T {
+    return when (type) {
+        is Int -> 42 as T
+        is String -> "Generic Method!" as T
+        else -> throw IllegalArgumentException("Unsupported type")
+    }
+}
+
+fun <T> passTypeUsingHigherOrderFunction(action: () -> T): T {
+    return action()
+}