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TypeVariable
public
interface
TypeVariable
implements
Type
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
Type[]
|
getBounds()
Returns an array of Type objects representing the
upper bound(s) of this type variable.
|
abstract
D
|
getGenericDeclaration()
Returns the GenericDeclaration object representing the
generic declaration declared this type variable.
|
abstract
String
|
getName()
Returns the name of this type variable, as it occurs in the source code.
|
Public methods
getBounds
public abstract Type[] getBounds ()
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
ParameterizedType for the
details of the creation process for parameterized types).
- Otherwise, B is resolved.
| Returns |
|---|
Type[] |
an array of Types representing the upper
bound(s) of this type variable |
getGenericDeclaration
public abstract D getGenericDeclaration ()
Returns the GenericDeclaration object representing the
generic declaration declared this type variable.
| Returns |
|---|
D |
the generic declaration declared for this type variable. |
getName
public abstract String getName ()
Returns the name of this type variable, as it occurs in the source code.
| Returns |
|---|
String |
the name of this type variable, as it appears in the source code |
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Last updated 2025-02-10 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-02-10 UTC."],[],[],null,["# TypeVariable\n\nAdded in [API level 1](/guide/topics/manifest/uses-sdk-element#ApiLevels) \nSummary: [Methods](#pubmethods) \\| [Inherited Methods](#inhmethods) \n\nTypeVariable\n============\n\n\n`\npublic\n\n\ninterface\nTypeVariable\n`\n\n\n`\n\n\nimplements\n\n`[Type](/reference/java/lang/reflect/Type)`\n\n\n`\n\n|-------------------------------------------------------------------------------------------------------------------------------------|\n| java.lang.reflect.TypeVariable\\\u003cD extends [java.lang.reflect.GenericDeclaration](/reference/java/lang/reflect/GenericDeclaration)\\\u003e |\n\n\u003cbr /\u003e\n\n*** ** * ** ***\n\nTypeVariable is the common superinterface for type variables of kinds.\nA type variable is created the first time it is needed by a reflective\nmethod, as specified in this package. If a type variable t is referenced\nby a type (i.e, class, interface or annotation type) T, and T is declared\nby the nth enclosing class of T (see JLS 8.1.2), then the creation of t\nrequires the resolution (see JVMS 5) of the ith enclosing class of T,\nfor i = 0 to n, inclusive. Creating a type variable must not cause the\ncreation of its bounds. Repeated creation of a type variable has no effect.\n\nMultiple objects may be instantiated at run-time to\nrepresent a given type variable. Even though a type variable is\ncreated only once, this does not imply any requirement to cache\ninstances representing the type variable. However, all instances\nrepresenting a type variable must be equal() to each other.\nAs a consequence, users of type variables must not rely on the identity\nof instances of classes implementing this interface.\n\nSummary\n-------\n\n| ### Public methods ||\n|---------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| ` abstract `[Type[]](/reference/java/lang/reflect/Type) | ` `[getBounds](/reference/java/lang/reflect/TypeVariable#getBounds())`() ` Returns an array of `Type` objects representing the upper bound(s) of this type variable. |\n| ` abstract D` | ` `[getGenericDeclaration](/reference/java/lang/reflect/TypeVariable#getGenericDeclaration())`() ` Returns the `GenericDeclaration` object representing the generic declaration declared this type variable. |\n| ` abstract `[String](/reference/java/lang/String) | ` `[getName](/reference/java/lang/reflect/TypeVariable#getName())`() ` Returns the name of this type variable, as it occurs in the source code. |\n\n| ### Inherited methods |\n|-----------------------|---|\n| From interface ` `[java.lang.reflect.Type](/reference/java/lang/reflect/Type)` ` |--------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------| | ` default `[String](/reference/java/lang/String) | ` `[getTypeName](/reference/java/lang/reflect/Type#getTypeName())`() ` Returns a string describing this type, including information about any type parameters. | ||\n\nPublic methods\n--------------\n\n### getBounds\n\nAdded in [API level 1](/guide/topics/manifest/uses-sdk-element#ApiLevels) \n\n```\npublic abstract Type[] getBounds ()\n```\n\nReturns an array of `Type` objects representing the\nupper bound(s) of this type variable. If no upper bound is\nexplicitly declared, the upper bound is `Object`.\n\nFor each upper bound B:\n\n- if B is a parameterized type or a type variable, it is created, (see [ParameterizedType](/reference/java/lang/reflect/ParameterizedType) for the details of the creation process for parameterized types).\n- Otherwise, B is resolved.\n\n\u003cbr /\u003e\n\n\u003cbr /\u003e\n\n| Returns ||\n|---------------------------------------------|----------------------------------------------------------------------------------|\n| [Type[]](/reference/java/lang/reflect/Type) | an array of `Type`s representing the upper bound(s) of this type variable \u003cbr /\u003e |\n\n| Throws ||\n|---------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------|\n| [TypeNotPresentException](/reference/java/lang/TypeNotPresentException) | if any of the bounds refers to a non-existent type declaration |\n| [MalformedParameterizedTypeException](/reference/java/lang/reflect/MalformedParameterizedTypeException) | if any of the bounds refer to a parameterized type that cannot be instantiated for any reason |\n\n### getGenericDeclaration\n\nAdded in [API level 1](/guide/topics/manifest/uses-sdk-element#ApiLevels) \n\n```\npublic abstract D getGenericDeclaration ()\n```\n\nReturns the `GenericDeclaration` object representing the\ngeneric declaration declared this type variable.\n\n\u003cbr /\u003e\n\n| Returns ||\n|-----|-----------------------------------------------------------------|\n| `D` | the generic declaration declared for this type variable. \u003cbr /\u003e |\n\n### getName\n\nAdded in [API level 1](/guide/topics/manifest/uses-sdk-element#ApiLevels) \n\n```\npublic abstract String getName ()\n```\n\nReturns the name of this type variable, as it occurs in the source code.\n\n\u003cbr /\u003e\n\n| Returns ||\n|---------------------------------------|-------------------------------------------------------------------------|\n| [String](/reference/java/lang/String) | the name of this type variable, as it appears in the source code \u003cbr /\u003e |"]]
