# TypeVariable Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels) # TypeVariable ``` interface TypeVariable : Type ``` |------------------------------------------------------------------------------------------------------------------| | [java.lang.reflect.TypeVariable](https://developer.android.com/reference/kotlin/java/lang/reflect/TypeVariable#) | TypeVariable is the common superinterface for type variables of kinds. A type variable is created the first time it is needed by a reflective method, as specified in this package. If a type variable t is referenced by a type (i.e, class, interface or annotation type) T, and T is declared by the nth enclosing class of T (see JLS 8.1.2), then the creation of t requires the resolution (see JVMS 5) of the ith enclosing class of T, for i = 0 to n, inclusive. Creating a type variable must not cause the creation of its bounds. Repeated creation of a type variable has no effect. Multiple objects may be instantiated at run-time to represent a given type variable. Even though a type variable is created only once, this does not imply any requirement to cache instances representing the type variable. However, all instances representing a type variable must be equal() to each other. As a consequence, users of type variables must not rely on the identity of instances of classes implementing this interface. ## Summary | Public methods || |--------------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | abstract[Array](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-array/index.html)\<[Type](https://developer.android.com/reference/kotlin/java/lang/reflect/Type)!\> | [getBounds](https://developer.android.com/reference/kotlin/java/lang/reflect/TypeVariable#getBounds())`()` Returns an array of`Type`objects representing the upper bound(s) of this type variable. | | abstractD | [getGenericDeclaration](https://developer.android.com/reference/kotlin/java/lang/reflect/TypeVariable#getGenericDeclaration())`()` Returns the`GenericDeclaration`object representing the generic declaration declared this type variable. | | abstract[String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html) | [getName](https://developer.android.com/reference/kotlin/java/lang/reflect/TypeVariable#getName())`()` Returns the name of this type variable, as it occurs in the source code. | | Inherited functions || |---|---| | From class[Type](https://developer.android.com/reference/kotlin/java/lang/reflect/Type) |----------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | [String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html) | [getTypeName](https://developer.android.com/reference/kotlin/java/lang/reflect/Type#getTypeName())`()`
Returns a string describing this type, including information about any type parameters.
| || ## Public methods ### getBounds Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels) ``` abstract fun getBounds(): Array ``` Returns an array of`Type`objects representing the upper bound(s) of this type variable. If no upper bound is explicitly declared, the upper bound is`Object`. For each upper bound B: - if B is a parameterized type or a type variable, it is created, (see for the details of the creation process for parameterized types). - Otherwise, B is resolved. | Return || |----------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------| | [Array](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-array/index.html)<[Type](https://developer.android.com/reference/kotlin/java/lang/reflect/Type)!> | an array of`Type`s representing the upper bound(s) of this type variable | | Exceptions || |---------------------------------------------------------|-----------------------------------------------------------------------------------------------| | `java.lang.TypeNotPresentException` | if any of the bounds refers to a non-existent type declaration | | `java.lang.reflect.MalformedParameterizedTypeException` | if any of the bounds refer to a parameterized type that cannot be instantiated for any reason | ### getGenericDeclaration Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels) ``` abstract fun getGenericDeclaration(): D ``` Returns the`GenericDeclaration`object representing the generic declaration declared this type variable. | Return || |---|----------------------------------------------------------| | D | the generic declaration declared for this type variable. | ### getName Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels) ``` abstract fun getName(): String ``` Returns the name of this type variable, as it occurs in the source code. | Return || |----------------------------------------------------------------------------------|------------------------------------------------------------------| | [String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html) | the name of this type variable, as it appears in the source code |