java.lang.Object
- com.google.javascript.rhino.jstype.JSType

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

AllType, BooleanType, NullType, NumberType, ObjectType, StringType, UnionType, VoidType
```
public abstract class JSType
extends java.lang.Object
implements java.io.Serializable
```
Represents JavaScript value types.
Types are split into two separate families: value types and object types. A special UnknownType exists to represent a wildcard type on which no information can be gathered. In particular, it can assign to everyone, is a subtype of everyone (and everyone is a subtype of it).
If you remove the UnknownType, the set of types in the type system forms a lattice with the isSubtype(com.google.javascript.rhino.jstype.JSType) relation defining the partial order of types. All types are united at the top of the lattice by the AllType and at the bottom by the NoType.

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class JSType.TypePair

Field Summary

Fields
Modifier and Type	Field	Description
`static java.lang.String`	`EMPTY_TYPE_COMPONENT`
`static int`	`ENUMDECL`
`static java.lang.String`	`NOT_A_CLASS`
`static java.lang.String`	`NOT_A_TYPE`
`static int`	`NOT_ENUMDECL`
`protected TemplateTypeMap`	`templateTypeMap`
`static java.lang.String`	`UNKNOWN_NAME`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`JSType`	`autobox()`	Dereference a type for property access.
`JSType`	`autoboxesTo()`	Turn a scalar type to the corresponding object type.
`boolean`	`canBeCalled()`	This predicate is used to test whether a given type can be used as the 'function' in a function call.
`boolean`	`canCastTo(JSType that)`	Tests whether values of `this` type can be safely assigned to values of `that` type.
`boolean`	`canTestForEqualityWith(JSType that)`	Tests whether `this` and `that` are meaningfully comparable.
`boolean`	`canTestForShallowEqualityWith(JSType that)`	Tests whether `this` and `that` are meaningfully comparable using shallow comparison.
`void`	`clearResolved()`	Clears the resolved field.
`JSType`	`collapseUnion()`	Gets the least supertype of this that's not a union.
`ObjectType`	`dereference()`	Dereference a type for property access.
`boolean`	`differsFrom(JSType that)`	Whether this type is meaningfully different from `that` type for the purposes of data flow analysis.
`boolean`	`equals(java.lang.Object jsType)`
`JSType`	`findPropertyType(java.lang.String propertyName)`	Coerces this type to an Object type, then gets the type of the property whose name is given.
`JSType`	`forceResolve(ErrorReporter t, StaticScope<JSType> scope)`	Force this type to resolve, even if the registry is in a lazy resolving mode.
`java.lang.String`	`getDisplayName()`	Returns a user meaningful label for the JSType instance.
`JSType`	`getGreatestSubtype(JSType that)`	Gets the greatest subtype of `this` and `that`.
`JSDocInfo`	`getJSDocInfo()`	Gets the docInfo for this type.
`JSType`	`getLeastSupertype(JSType that)`	Gets the least supertype of `this` and `that`.
`abstract BooleanLiteralSet`	`getPossibleToBooleanOutcomes()`	Computes the set of possible outcomes of the `ToBoolean` predicate for this type.
`JSType`	`getRestrictedTypeGivenToBooleanOutcome(boolean outcome)`	Computes the restricted type of this type knowing that the `ToBoolean` predicate has a specific value.
`TemplateTypeMap`	`getTemplateTypeMap()`	Returns the template type map associated with this type.
`JSType.TypePair`	`getTypesUnderEquality(JSType that)`	Computes the subset of `this` and `that` types if equality is observed.
`JSType.TypePair`	`getTypesUnderInequality(JSType that)`	Computes the subset of `this` and `that` types if inequality is observed.
`JSType.TypePair`	`getTypesUnderShallowEquality(JSType that)`	Computes the subset of `this` and `that` types under shallow equality.
`JSType.TypePair`	`getTypesUnderShallowInequality(JSType that)`	Computes the subset of `this` and `that` types under shallow inequality.
`boolean`	`hasAnyTemplateTypes()`
`boolean`	`hasDisplayName()`
`int`	`hashCode()`
`boolean`	`hasProperty(java.lang.String pname)`	Checks whether the property is present on the object.
`boolean`	`isAllType()`
`boolean`	`isArrayType()`
`boolean`	`isBooleanObjectType()`
`boolean`	`isBooleanValueType()`
`boolean`	`isCheckedUnknownType()`
`boolean`	`isConstructor()`	Whether this type is a `FunctionType` that is a constructor or a named type that points to such a type.
`boolean`	`isDateType()`
`boolean`	`isDict()`	Returns true iff `this` can be a `dict`.
`boolean`	`isEmptyType()`
`boolean`	`isEnumElementType()`
`boolean`	`isEnumType()`
`static boolean`	`isEquivalent(JSType typeA, JSType typeB)`
`boolean`	`isEquivalentTo(JSType that)`	Checks if two types are equivalent.
`boolean`	`isFunctionPrototypeType()`	Whether this is the prototype of a function.
`boolean`	`isFunctionType()`	Returns true if toMaybeFunctionType returns a non-null FunctionType.
`boolean`	`isGlobalThisType()`	Returns true if this is a global this type.
`boolean`	`isInstanceType()`	Whether this type is an Instance object of some constructor.
`boolean`	`isInterface()`	Whether this type is a `FunctionType` that is an interface or a named type that points to such a type.
`boolean`	`isInvariant(JSType that)`	Checks if two types are invariant.
`boolean`	`isNominalConstructor()`	Whether this type is the original constructor of a nominal type.
`boolean`	`isNominalType()`	Whether this type is a nominal type (a named instance object or a named enum).
`boolean`	`isNoObjectType()`
`boolean`	`isNoResolvedType()`
`boolean`	`isNoType()`
`boolean`	`isNullable()`	Tests whether this type is nullable.
`boolean`	`isNullType()`
`boolean`	`isNumber()`	Tests whether the type is a number (value or Object).
`boolean`	`isNumberObjectType()`
`boolean`	`isNumberValueType()`
`boolean`	`isObject()`	Tests whether this type is an `Object`, or any subtype thereof.
`boolean`	`isOrdinaryFunction()`	Whether this type is a `FunctionType` that is an ordinary function or a named type that points to such a type.
`boolean`	`isRecordType()`
`boolean`	`isRegexpType()`
`boolean`	`isResolved()`	Whether the type has been resolved.
`boolean`	`isString()`	Tests whether the type is a string (value or Object).
`boolean`	`isStringObjectType()`
`boolean`	`isStringValueType()`
`boolean`	`isStruct()`	Returns true iff `this` can be a `struct`.
`boolean`	`isSubtype(JSType that)`	Checks whether `this` is a subtype of `that`.
`boolean`	`isTemplateType()`
`boolean`	`isTemplatizedType()`
`boolean`	`isUnionType()`
`boolean`	`isUnknownType()`
`boolean`	`isVoidType()`
`void`	`matchConstraint(JSType constraint)`	Modify this type so that it matches the specified type.
`boolean`	`matchesInt32Context()`	This predicate is used to test whether a given type can appear in a 'Int32' context.
`boolean`	`matchesNumberContext()`	This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator.
`boolean`	`matchesObjectContext()`	This predicate is used to test whether a given type can appear in an `Object` context, such as the expression in a with statement.
`boolean`	`matchesStringContext()`	This predicate is used to test whether a given type can appear in a `String` context, such as an operand of a string concat (+) operator.
`boolean`	`matchesUint32Context()`	This predicate is used to test whether a given type can appear in a 'Uint32' context.
`JSType`	`resolve(ErrorReporter t, StaticScope<JSType> scope)`	Resolve this type in the given scope.
`JSType`	`restrictByNotNullOrUndefined()`	If this is a union type, returns a union type that does not include the null or undefined type.
`boolean`	`setValidator(com.google.common.base.Predicate<JSType> validator)`	Certain types have constraints on them at resolution-time.
`TernaryValue`	`testForEquality(JSType that)`	Compares `this` and `that`.
`java.lang.String`	`toAnnotationString()`	A string representation of this type, suitable for printing in type annotations at code generation time.
`java.lang.String`	`toDebugHashCodeString()`	A hash code function for diagnosing complicated issues around type-identity.
`EnumElementType`	`toMaybeEnumElementType()`	Downcasts this to an EnumElementType, or returns null if this is not an EnumElementType.
`EnumType`	`toMaybeEnumType()`	Downcasts this to an EnumType, or returns null if this is not an EnumType.
`FunctionType`	`toMaybeFunctionType()`	Downcasts this to a FunctionType, or returns null if this is not a function.
`static FunctionType`	`toMaybeFunctionType(JSType type)`	Null-safe version of toMaybeFunctionType().
`TemplateType`	`toMaybeTemplateType()`	Downcasts this to a TemplateType, or returns null if this is not a function.
`static TemplateType`	`toMaybeTemplateType(JSType type)`	Null-safe version of toMaybeTemplateType().
`TemplatizedType`	`toMaybeTemplatizedType()`	Downcasts this to a TemplatizedType, or returns null if this is not a function.
`static TemplatizedType`	`toMaybeTemplatizedType(JSType type)`	Null-safe version of toMaybeTemplatizedType().
`UnionType`	`toMaybeUnionType()`	Downcasts this to a UnionType, or returns null if this is not a UnionType.
`ObjectType`	`toObjectType()`	Casts this to an ObjectType, or returns null if this is not an ObjectType.
`java.lang.String`	`toString()`	A string representation of this type, suitable for printing in warnings.
`JSType`	`unboxesTo()`	Turn an object type to its corresponding scalar type.
`abstract <T> T`	`visit(Visitor<T> visitor)`	Visit this type with the given visitor.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
 - templateTypeMap
```
protected final TemplateTypeMap templateTypeMap
```
 - UNKNOWN_NAME
```
public static final java.lang.String UNKNOWN_NAME
```
 See Also:
 
 Constant Field Values
 - NOT_A_CLASS
```
public static final java.lang.String NOT_A_CLASS
```
 See Also:
 
 Constant Field Values
 - NOT_A_TYPE
```
public static final java.lang.String NOT_A_TYPE
```
 See Also:
 
 Constant Field Values
 - EMPTY_TYPE_COMPONENT
```
public static final java.lang.String EMPTY_TYPE_COMPONENT
```
 See Also:
 
 Constant Field Values
 - ENUMDECL
```
public static final int ENUMDECL
```
 See Also:
 
 Constant Field Values
 - NOT_ENUMDECL
```
public static final int NOT_ENUMDECL
```
 See Also:
 
 Constant Field Values
- Method Detail
 - getJSDocInfo
```
public JSDocInfo getJSDocInfo()
```
 Gets the docInfo for this type. By default, documentation cannot be attached to arbitrary types. This must be overridden for programmer-defined types.
 - getDisplayName
```
public java.lang.String getDisplayName()
```
 Returns a user meaningful label for the JSType instance. For example, Functions and Enums will return their declaration name (if they have one). Some types will not have a meaningful display name. Calls to hasDisplayName() will return true IFF getDisplayName() will return null or a zero length string.
 
 Returns:
 
 the display name of the type, or null if one is not available
 - hasDisplayName
```
public boolean hasDisplayName()
```
 Returns:
 
 true if the JSType has a user meaningful label.
 - hasProperty
```
public boolean hasProperty(java.lang.String pname)
```
 Checks whether the property is present on the object.
 
 Parameters:
 
 pname - The property name.
 - isNoType
```
public boolean isNoType()
```
 - isNoResolvedType
```
public boolean isNoResolvedType()
```
 - isNoObjectType
```
public boolean isNoObjectType()
```
 - isEmptyType
```
public final boolean isEmptyType()
```
 - isNumberObjectType
```
public boolean isNumberObjectType()
```
 - isNumberValueType
```
public boolean isNumberValueType()
```
 - isFunctionPrototypeType
```
public boolean isFunctionPrototypeType()
```
 Whether this is the prototype of a function.
 - isStringObjectType
```
public boolean isStringObjectType()
```
 - isStringValueType
```
public boolean isStringValueType()
```
 - isString
```
public final boolean isString()
```
 Tests whether the type is a string (value or Object).
 
 Returns:
 
 this <: (String, string)
 - isNumber
```
public final boolean isNumber()
```
 Tests whether the type is a number (value or Object).
 
 Returns:
 
 this <: (Number, number)
 - isArrayType
```
public boolean isArrayType()
```
 - isBooleanObjectType
```
public boolean isBooleanObjectType()
```
 - isBooleanValueType
```
public boolean isBooleanValueType()
```
 - isRegexpType
```
public boolean isRegexpType()
```
 - isDateType
```
public boolean isDateType()
```
 - isNullType
```
public boolean isNullType()
```
 - isVoidType
```
public boolean isVoidType()
```
 - isAllType
```
public boolean isAllType()
```
 - isUnknownType
```
public boolean isUnknownType()
```
 - isCheckedUnknownType
```
public boolean isCheckedUnknownType()
```
 - isUnionType
```
public final boolean isUnionType()
```
 - isStruct
```
public boolean isStruct()
```
 Returns true iff this can be a struct. UnionType overrides the method, assume this is not a union here.
 - isDict
```
public boolean isDict()
```
 Returns true iff this can be a dict. UnionType overrides the method, assume this is not a union here.
 - toMaybeUnionType
```
public UnionType toMaybeUnionType()
```
 Downcasts this to a UnionType, or returns null if this is not a UnionType. Named in honor of Haskell's Maybe type constructor.
 - isGlobalThisType
```
public final boolean isGlobalThisType()
```
 Returns true if this is a global this type.
 - isFunctionType
```
public final boolean isFunctionType()
```
 Returns true if toMaybeFunctionType returns a non-null FunctionType.
 - toMaybeFunctionType
```
public FunctionType toMaybeFunctionType()
```
 Downcasts this to a FunctionType, or returns null if this is not a function. For the purposes of this function, we define a MaybeFunctionType as any type in the sub-lattice { x | LEAST_FUNCTION_TYPE <= x <= GREATEST_FUNCTION_TYPE } This definition excludes bottom types like NoType and NoObjectType. This definition is somewhat arbitrary and axiomatic, but this is the definition that makes the most sense for the most callers.
 - toMaybeFunctionType
```
public static FunctionType toMaybeFunctionType(JSType type)
```
 Null-safe version of toMaybeFunctionType().
 - isEnumElementType
```
public final boolean isEnumElementType()
```
 - toMaybeEnumElementType
```
public EnumElementType toMaybeEnumElementType()
```
 Downcasts this to an EnumElementType, or returns null if this is not an EnumElementType.
 - isEnumType
```
public boolean isEnumType()
```
 - toMaybeEnumType
```
public EnumType toMaybeEnumType()
```
 Downcasts this to an EnumType, or returns null if this is not an EnumType.
 - isRecordType
```
public boolean isRecordType()
```
 - isTemplatizedType
```
public final boolean isTemplatizedType()
```
 - toMaybeTemplatizedType
```
public TemplatizedType toMaybeTemplatizedType()
```
 Downcasts this to a TemplatizedType, or returns null if this is not a function.
 - toMaybeTemplatizedType
```
public static TemplatizedType toMaybeTemplatizedType(JSType type)
```
 Null-safe version of toMaybeTemplatizedType().
 - isTemplateType
```
public final boolean isTemplateType()
```
 - toMaybeTemplateType
```
public TemplateType toMaybeTemplateType()
```
 Downcasts this to a TemplateType, or returns null if this is not a function.
 - toMaybeTemplateType
```
public static TemplateType toMaybeTemplateType(JSType type)
```
 Null-safe version of toMaybeTemplateType().
 - hasAnyTemplateTypes
```
public boolean hasAnyTemplateTypes()
```
 - getTemplateTypeMap
```
public TemplateTypeMap getTemplateTypeMap()
```
 Returns the template type map associated with this type.
 - isObject
```
public boolean isObject()
```
 Tests whether this type is an Object, or any subtype thereof.
 
 Returns:
 
 this <: Object
 - isConstructor
```
public boolean isConstructor()
```
 Whether this type is a FunctionType that is a constructor or a named type that points to such a type.
 - isNominalType
```
public boolean isNominalType()
```
 Whether this type is a nominal type (a named instance object or a named enum).
 - isNominalConstructor
```
public final boolean isNominalConstructor()
```
 Whether this type is the original constructor of a nominal type. Does not include structural constructors.
 - isInstanceType
```
public boolean isInstanceType()
```
 Whether this type is an Instance object of some constructor. Does not necessarily mean this is an InstanceObjectType.
 - isInterface
```
public boolean isInterface()
```
 Whether this type is a FunctionType that is an interface or a named type that points to such a type.
 - isOrdinaryFunction
```
public boolean isOrdinaryFunction()
```
 Whether this type is a FunctionType that is an ordinary function or a named type that points to such a type.
 - isEquivalentTo
```
public final boolean isEquivalentTo(JSType that)
```
 Checks if two types are equivalent.
 - isInvariant
```
public final boolean isInvariant(JSType that)
```
 Checks if two types are invariant.
 
 See Also:
 
 EquivalenceMethod
 - differsFrom
```
public final boolean differsFrom(JSType that)
```
 Whether this type is meaningfully different from that type for the purposes of data flow analysis. This is a trickier check than pure equality, because it has to properly handle unknown types. See EquivalenceMethod for more info.
 
 See Also:
 
 Unknown unknowns
 - isEquivalent
```
public static boolean isEquivalent(JSType typeA,
 JSType typeB)
```
 - equals
```
public boolean equals(java.lang.Object jsType)
```
 Overrides:
 
 equals in class java.lang.Object
 - hashCode
```
public int hashCode()
```
 Overrides:
 
 hashCode in class java.lang.Object
 - matchesInt32Context
```
public final boolean matchesInt32Context()
```
 This predicate is used to test whether a given type can appear in a 'Int32' context. This context includes, for example, the operands of a bitwise or operator. Since we do not currently support integer types, this is a synonym for Number.
 - matchesUint32Context
```
public final boolean matchesUint32Context()
```
 This predicate is used to test whether a given type can appear in a 'Uint32' context. This context includes the right-hand operand of a shift operator.
 - matchesNumberContext
```
public boolean matchesNumberContext()
```
 This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator.
 - matchesStringContext
```
public boolean matchesStringContext()
```
 This predicate is used to test whether a given type can appear in a String context, such as an operand of a string concat (+) operator. All types have at least the potential for converting to String. When we add externally defined types, such as a browser OM, we may choose to add types that do not automatically convert to String.
 - matchesObjectContext
```
public boolean matchesObjectContext()
```
 This predicate is used to test whether a given type can appear in an Object context, such as the expression in a with statement. Most types we will encounter, except notably null, have at least the potential for converting to Object. Host defined objects can get peculiar.
 - findPropertyType
```
public JSType findPropertyType(java.lang.String propertyName)
```
 Coerces this type to an Object type, then gets the type of the property whose name is given. Unlike ObjectType.getPropertyType(java.lang.String), returns null if the property is not found.
 
 Returns:
 
 The property's type. null if the current type cannot have properties, or if the type is not found.
 - canBeCalled
```
public boolean canBeCalled()
```
 This predicate is used to test whether a given type can be used as the 'function' in a function call.
 
 Returns:
 
 true if this type might be callable.
 - canCastTo
```
public boolean canCastTo(JSType that)
```
 Tests whether values of this type can be safely assigned to values of that type.
 The default implementation verifies that this is a subtype of that.
 - autoboxesTo
```
public JSType autoboxesTo()
```
 Turn a scalar type to the corresponding object type.
 
 Returns:
 
 the auto-boxed type or null if this type is not a scalar.
 - unboxesTo
```
public JSType unboxesTo()
```
 Turn an object type to its corresponding scalar type.
 
 Returns:
 
 the unboxed type or null if this type does not unbox.
 - toObjectType
```
public ObjectType toObjectType()
```
 Casts this to an ObjectType, or returns null if this is not an ObjectType. If this is a scalar type, it will *not* be converted to an object type. If you want to simulate JS autoboxing or dereferencing, you should use autoboxesTo() or dereference().
 - autobox
```
public JSType autobox()
```
 Dereference a type for property access. Filters null/undefined and autoboxes the resulting type. Never returns null.
 - dereference
```
public final ObjectType dereference()
```
 Dereference a type for property access. Filters null/undefined, autoboxes the resulting type, and returns it iff it's an object.
 - canTestForEqualityWith
```
public final boolean canTestForEqualityWith(JSType that)
```
 Tests whether this and that are meaningfully comparable. By meaningfully, we mean compatible types that do not lead to step 22 of the definition of the Abstract Equality Comparison Algorithm (11.9.3, page 55–56) of the ECMA-262 specification.
 - testForEquality
```
public TernaryValue testForEquality(JSType that)
```
 Compares this and that.
 Returns:
 
 TernaryValue.TRUE if the comparison of values of this type and that always succeed (such as undefined compared to null)
 
 TernaryValue.FALSE if the comparison of values of this type and that always fails (such as undefined compared to number)
 
 TernaryValue.UNKNOWN if the comparison can succeed or fail depending on the concrete values
 - canTestForShallowEqualityWith
```
public final boolean canTestForShallowEqualityWith(JSType that)
```
 Tests whether this and that are meaningfully comparable using shallow comparison. By meaningfully, we mean compatible types that are not rejected by step 1 of the definition of the Strict Equality Comparison Algorithm (11.9.6, page 56–57) of the ECMA-262 specification.
 - isNullable
```
public boolean isNullable()
```
 Tests whether this type is nullable.
 - collapseUnion
```
public JSType collapseUnion()
```
 Gets the least supertype of this that's not a union.
 - getLeastSupertype
```
public JSType getLeastSupertype(JSType that)
```
 Gets the least supertype of this and that. The least supertype is the join (∨) or supremum of both types in the type lattice.
 Examples:
 
 number ∨ * = *
 
 number ∨ Object = (number, Object)
 
 Number ∨ Object = Object
 Returns:
 
 this ∨ that
 - getGreatestSubtype
```
public JSType getGreatestSubtype(JSType that)
```
 Gets the greatest subtype of this and that. The greatest subtype is the meet (∧) or infimum of both types in the type lattice.
 Examples
 
 Number ∧ Any = Any
 
 number ∧ Object = Any
 
 Number ∧ Object = Number
 Returns:
 
 this ∨ that
 - getRestrictedTypeGivenToBooleanOutcome
```
public JSType getRestrictedTypeGivenToBooleanOutcome(boolean outcome)
```
 Computes the restricted type of this type knowing that the ToBoolean predicate has a specific value. For more information about the ToBoolean predicate, see getPossibleToBooleanOutcomes().
 
 Parameters:
 
 outcome - the value of the ToBoolean predicate
 
 Returns:
 
 the restricted type, or the Any Type if the underlying type could not have yielded this ToBoolean value TODO(user): Move this method to the SemanticRAI and use the visit method of types to get the restricted type.
 - getPossibleToBooleanOutcomes
```
public abstract BooleanLiteralSet getPossibleToBooleanOutcomes()
```
 Computes the set of possible outcomes of the ToBoolean predicate for this type. The ToBoolean predicate is defined by the ECMA-262 standard, 3^rd edition. Its behavior for simple types can be summarized by the following table:
 
 type result
 
 undefined {false}
 
 null {false}
 
 boolean {true, false}
 
 number {true, false}
 
 string {true, false}
 
 Object {true}
 
 Returns:
 
 the set of boolean literals for this type
 - getTypesUnderEquality
```
public JSType.TypePair getTypesUnderEquality(JSType that)
```
 Computes the subset of this and that types if equality is observed. If a value v1 of type null is equal to a value v2 of type (undefined,number), we can infer that the type of v1 is null and the type of v2 is undefined.
 
 Returns:
 
 a pair containing the restricted type of this as the first component and the restricted type of that as the second element. The returned pair is never null even though its components may be null
 - getTypesUnderInequality
```
public JSType.TypePair getTypesUnderInequality(JSType that)
```
 Computes the subset of this and that types if inequality is observed. If a value v1 of type number is not equal to a value v2 of type (undefined,number), we can infer that the type of v1 is number and the type of v2 is number as well.
 
 Returns:
 
 a pair containing the restricted type of this as the first component and the restricted type of that as the second element. The returned pair is never null even though its components may be null
 - getTypesUnderShallowEquality
```
public JSType.TypePair getTypesUnderShallowEquality(JSType that)
```
 Computes the subset of this and that types under shallow equality.
 
 Returns:
 
 a pair containing the restricted type of this as the first component and the restricted type of that as the second element. The returned pair is never null even though its components may be null.
 - getTypesUnderShallowInequality
```
public JSType.TypePair getTypesUnderShallowInequality(JSType that)
```
 Computes the subset of this and that types under shallow inequality.
 
 Returns:
 
 A pair containing the restricted type of this as the first component and the restricted type of that as the second element. The returned pair is never null even though its components may be null
 - restrictByNotNullOrUndefined
```
public JSType restrictByNotNullOrUndefined()
```
 If this is a union type, returns a union type that does not include the null or undefined type.
 - isSubtype
```
public boolean isSubtype(JSType that)
```
 Checks whether this is a subtype of that.
 Subtyping rules:
 
 (unknown) — every type is a subtype of the Unknown type.
 
 (no) — the No type is a subtype of every type.
 
 (no-object) — the NoObject type is a subtype of every object type (i.e. subtypes of the Object type).
 
 (ref) — a type is a subtype of itself.
 
 (union-l) — A union type is a subtype of a type U if all the union type's constituents are a subtype of U. Formally
 (T1, …, Tn) <: U if and only Tk <: U for all k ∈ 1..n.
 
 (union-r) — A type U is a subtype of a union type if it is a subtype of one of the union type's constituents. Formally
 U <: (T1, …, Tn) if and only if U <: Tk for some index k.
 
 (objects) — an Object O1 is a subtype of an object O2 if it has more properties than O2 and all common properties are pairwise subtypes.
 Returns:
 
 this <: that
 - visit
```
public abstract <T> T visit(Visitor<T> visitor)
```
 Visit this type with the given visitor.
 
 Returns:
 
 the value returned by the visitor
 
 See Also:
 
 Visitor
 - forceResolve
```
public final JSType forceResolve(ErrorReporter t,
 StaticScope<JSType> scope)
```
 Force this type to resolve, even if the registry is in a lazy resolving mode.
 
 See Also:
 
 resolve(com.google.javascript.rhino.ErrorReporter, com.google.javascript.rhino.jstype.StaticScope<com.google.javascript.rhino.jstype.JSType>)
 - resolve
```
public final JSType resolve(ErrorReporter t,
 StaticScope<JSType> scope)
```
 Resolve this type in the given scope. The returned value must be equal to this, as defined by isEquivalentTo(com.google.javascript.rhino.jstype.JSType). It may or may not be the same object. This method may modify the internal state of this, as long as it does so in a way that preserves Object equality. For efficiency, we should only resolve a type once per compilation job. For incremental compilations, one compilation job may need the artifacts from a previous generation, so we will eventually need a generational flag instead of a boolean one.
 - isResolved
```
public final boolean isResolved()
```
 Whether the type has been resolved.
 - clearResolved
```
public final void clearResolved()
```
 Clears the resolved field.
 - setValidator
```
public boolean setValidator(com.google.common.base.Predicate<JSType> validator)
```
 Certain types have constraints on them at resolution-time. For example, a type in an @extends annotation must be an object. Clients should inject a validator that emits a warning if the type does not validate, and return false.
 - toString
```
public java.lang.String toString()
```
 A string representation of this type, suitable for printing in warnings.
 
 Overrides:
 
 toString in class java.lang.Object
 - toDebugHashCodeString
```
public java.lang.String toDebugHashCodeString()
```
 A hash code function for diagnosing complicated issues around type-identity.
 - toAnnotationString
```
public final java.lang.String toAnnotationString()
```
 A string representation of this type, suitable for printing in type annotations at code generation time.
 - matchConstraint
```
public void matchConstraint(JSType constraint)
```
 Modify this type so that it matches the specified type. This is useful for reverse type-inference, where we want to infer that an object literal matches its constraint (much like how the java compiler does reverse-inference to figure out generics).
 
 Parameters:
 
 constraint -

type	result
`undefined`	{false}
`null`	{false}
`boolean`	{true, false}
`number`	{true, false}
`string`	{true, false}
`Object`	{true}

Class JSType

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

templateTypeMap

UNKNOWN_NAME

NOT_A_CLASS

NOT_A_TYPE

EMPTY_TYPE_COMPONENT

ENUMDECL

NOT_ENUMDECL

Method Detail

getJSDocInfo

getDisplayName

hasDisplayName

hasProperty

isNoType

isNoResolvedType

isNoObjectType

isEmptyType

isNumberObjectType

isNumberValueType

isFunctionPrototypeType

isStringObjectType

isStringValueType

isString

isNumber

isArrayType

isBooleanObjectType

isBooleanValueType

isRegexpType

isDateType

isNullType

isVoidType

isAllType

isUnknownType

isCheckedUnknownType

isUnionType

isStruct

isDict

toMaybeUnionType

isGlobalThisType

isFunctionType

toMaybeFunctionType

toMaybeFunctionType

isEnumElementType

toMaybeEnumElementType

isEnumType

toMaybeEnumType

isRecordType

isTemplatizedType

toMaybeTemplatizedType

toMaybeTemplatizedType

isTemplateType

toMaybeTemplateType

toMaybeTemplateType

hasAnyTemplateTypes

getTemplateTypeMap

isObject

isConstructor

isNominalType

isNominalConstructor

isInstanceType

isInterface

isOrdinaryFunction

isEquivalentTo

isInvariant

differsFrom

isEquivalent

equals

hashCode

matchesInt32Context

matchesUint32Context

matchesNumberContext

matchesStringContext

matchesObjectContext

findPropertyType

canBeCalled