com.google.javascript.rhino.jstype
Class NoObjectType

java.lang.Object
  extended by com.google.javascript.rhino.jstype.JSType
      extended by com.google.javascript.rhino.jstype.ObjectType
          extended by com.google.javascript.rhino.jstype.FunctionType
              extended by com.google.javascript.rhino.jstype.NoObjectType
All Implemented Interfaces:
StaticScope<JSType>, Serializable
Direct Known Subclasses:
NoType

public class NoObjectType
extends FunctionType

The bottom Object type, representing the subclass of all objects. Although JavaScript programmers can't explicitly denote the bottom Object type, it comes up in static analysis. For example, if we have: var x = function() {}; if (x instanceof Array) { f(x); } We need to be able to assign x a type within the f(x) call. It has no possible type, but x would not be legal if f expected a string. So we assign it the NoObjectType.

See Also:
Bottom types, Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.ObjectType
ObjectType.Property
 
Nested classes/interfaces inherited from class com.google.javascript.rhino.jstype.JSType
JSType.TypePair
 
Field Summary
 
Fields inherited from class com.google.javascript.rhino.jstype.JSType
EMPTY_TYPE_COMPONENT, ENUMDECL, NOT_A_CLASS, NOT_A_TYPE, NOT_ENUMDECL, UNKNOWN_NAME
 
Method Summary
 FunctionType getConstructor()
          Gets this object's constructor.
 Iterable<ObjectType> getCtorExtendedInterfaces()
          Gets the interfaces extended by the interface associated with this type.
 Iterable<ObjectType> getCtorImplementedInterfaces()
          Gets the interfaces implemented by the ctor associated with this type.
 ObjectType getImplicitPrototype()
          Gets the implicit prototype (a.k.a.
 FunctionType getOwnerFunction()
          Gets the owner of this if it's a function prototype.
 JSDocInfo getOwnPropertyJSDocInfo(String propertyName)
          Gets the docInfo on the specified property on this type.
 int getPropertiesCount()
          Gets the number of properties of this object.
 Node getPropertyNode(String propertyName)
          Gets the node corresponding to the definition of the specified property.
 JSType getPropertyType(String propertyName)
          Gets the property type of the property whose name is given.
 String getReferenceName()
          Gets the reference name for this object.
 int hashCode()
           
 boolean hasOwnProperty(String propertyName)
          Checks whether the property whose name is given is present directly on the object.
 boolean hasProperty(String propertyName)
          Checks whether the property whose name is given is present on the object.
 boolean hasReferenceName()
          Returns true if the object is named.
 boolean isEquivalentTo(JSType that)
          Two function types are equal if their signatures match.
 boolean isNativeObjectType()
          Whether this is a built-in object.
 boolean isNoObjectType()
           
 boolean isPropertyInExterns(String propertyName)
          Checks whether the property was defined in the externs.
 boolean isPropertyTypeDeclared(String property)
          Checks whether the property's type is declared.
 boolean isPropertyTypeInferred(String propertyName)
          Checks whether the property's type is inferred.
 boolean isSubtype(JSType that)
          A function is a subtype of another if their call methods are related via subtyping and this is a subtype of that with regard to the prototype chain.
 void matchConstraint(ObjectType constraintObj)
          Modify this type so that it matches the specified type.
 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 removeProperty(String name)
          Removes the declared or inferred property from this ObjectType.
 void setPropertyJSDocInfo(String propertyName, JSDocInfo info)
          Sets the docInfo for the specified property from the JSDocInfo on its definition.
 FunctionType toMaybeFunctionType()
          Downcasts this to a FunctionType, or returns null if this is not a function.
 JSType unboxesTo()
          Gets the type to which this type unboxes.
<T> T
visit(Visitor<T> visitor)
          Visit this type with the given visitor.
 
Methods inherited from class com.google.javascript.rhino.jstype.FunctionType
canBeCalled, clearCachedValues, getAllExtendedInterfaces, getAllImplementedInterfaces, getBindReturnType, getExtendedInterfaces, getExtendedInterfacesCount, getImplementedInterfaces, getInstanceType, getMaxArguments, getMinArguments, getOwnImplementedInterfaces, getOwnPropertyNames, getParameters, getParametersNode, getPrototype, getReturnType, getSlot, getSource, getSubTypes, getSuperClassConstructor, getTemplateTypeName, getTopDefiningInterface, getTopMostDefiningType, getTypeOfThis, hasCachedValues, hasEqualCallType, hasImplementedInterfaces, hasInstanceType, isConstructor, isInstanceType, isInterface, isOrdinaryFunction, isReturnTypeInferred, setExtendedInterfaces, setImplementedInterfaces, setPrototypeBasedOn, setSource, toDebugHashCodeString
 
Methods inherited from class com.google.javascript.rhino.jstype.ObjectType
cast, createDelegateSuffix, defineDeclaredProperty, defineInferredProperty, findPropertyType, getDisplayName, getIndexType, getJSDocInfo, getNormalizedReferenceName, getOwnSlot, getParameterType, getParentScope, getPossibleToBooleanOutcomes, getPropertyNames, getRootNode, isFunctionPrototypeType, isObject, isUnknownType, setJSDocInfo, testForEquality
 
Methods inherited from class com.google.javascript.rhino.jstype.JSType
autobox, autoboxesTo, canAssignTo, canTestForEqualityWith, canTestForShallowEqualityWith, clearResolved, collapseUnion, dereference, differsFrom, equals, forceResolve, getGreatestSubtype, getLeastSupertype, getRestrictedTypeGivenToBooleanOutcome, getTypesUnderEquality, getTypesUnderInequality, getTypesUnderShallowEquality, getTypesUnderShallowInequality, hasDisplayName, isAllType, isArrayType, isBooleanObjectType, isBooleanValueType, isCheckedUnknownType, isDateType, isEmptyType, isEnumElementType, isEnumType, isEquivalent, isFunctionType, isGlobalThisType, isNominalConstructor, isNominalType, isNoResolvedType, isNoType, isNullable, isNullType, isNumber, isNumberObjectType, isNumberValueType, isRecordType, isRegexpType, isResolved, isString, isStringObjectType, isStringValueType, isTemplateType, isUnionType, isVoidType, matchesInt32Context, matchesUint32Context, resolve, restrictByNotNullOrUndefined, setValidator, toAnnotationString, toMaybeEnumElementType, toMaybeEnumType, toMaybeFunctionType, toMaybeUnionType, toObjectType, toString
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
 

Method Detail

isSubtype

public boolean isSubtype(JSType that)
Description copied from class: FunctionType
A function is a subtype of another if their call methods are related via subtyping and this is a subtype of that with regard to the prototype chain.

Overrides:
isSubtype in class FunctionType
Returns:
this &lt;: that

toMaybeFunctionType

public FunctionType toMaybeFunctionType()
Description copied from class: JSType
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.

Overrides:
toMaybeFunctionType in class FunctionType

isNoObjectType

public boolean isNoObjectType()
Overrides:
isNoObjectType in class JSType

getImplicitPrototype

public ObjectType getImplicitPrototype()
Description copied from class: ObjectType
Gets the implicit prototype (a.k.a. the [[Prototype]] property).


getReferenceName

public String getReferenceName()
Description copied from class: ObjectType
Gets the reference name for this object. This includes named types like constructors, prototypes, and enums. It notably does not include literal types like strings and booleans and structural types.

Returns:
the object's name or null if this is an anonymous object

matchesNumberContext

public boolean matchesNumberContext()
Description copied from class: JSType
This predicate is used to test whether a given type can appear in a numeric context, such as an operand of a multiply operator.


matchesObjectContext

public boolean matchesObjectContext()
Description copied from class: JSType
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.


matchesStringContext

public boolean matchesStringContext()
Description copied from class: JSType
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.


isEquivalentTo

public boolean isEquivalentTo(JSType that)
Description copied from class: FunctionType
Two function types are equal if their signatures match. Since they don't have signatures, two interfaces are equal if their names match.

Overrides:
isEquivalentTo in class FunctionType

hashCode

public int hashCode()
Overrides:
hashCode in class FunctionType

getPropertiesCount

public int getPropertiesCount()
Gets the number of properties of this object.


getPropertyType

public JSType getPropertyType(String propertyName)
Description copied from class: ObjectType
Gets the property type of the property whose name is given. If the underlying object does not have this property, the Unknown type is returned to indicate that no information is available on this property.

Overrides:
getPropertyType in class FunctionType
Returns:
the property's type or UnknownType. This method never returns null.

hasProperty

public boolean hasProperty(String propertyName)
Description copied from class: ObjectType
Checks whether the property whose name is given is present on the object.


removeProperty

public boolean removeProperty(String name)
Description copied from class: ObjectType
Removes the declared or inferred property from this ObjectType.

Parameters:
name - the property's name
Returns:
true if the property was removed successfully. False if the property did not exist, or could not be removed.

getOwnPropertyJSDocInfo

public JSDocInfo getOwnPropertyJSDocInfo(String propertyName)
Description copied from class: ObjectType
Gets the docInfo on the specified property on this type. This should not be done implemented recursively, as you generally need to know exactly on which type in the prototype chain the JSDocInfo exists.


setPropertyJSDocInfo

public void setPropertyJSDocInfo(String propertyName,
                                 JSDocInfo info)
Description copied from class: ObjectType
Sets the docInfo for the specified property from the JSDocInfo on its definition.

info - JSDocInfo for the property definition. May be null.

isPropertyTypeInferred

public boolean isPropertyTypeInferred(String propertyName)
Description copied from class: ObjectType
Checks whether the property's type is inferred.


visit

public <T> T visit(Visitor<T> visitor)
Description copied from class: JSType
Visit this type with the given visitor.

Overrides:
visit in class FunctionType
Returns:
the value returned by the visitor
See Also:
Visitor

getConstructor

public FunctionType getConstructor()
Description copied from class: ObjectType
Gets this object's constructor.

Returns:
this object's constructor or null if it is a native object (constructed natively v.s. by instantiation of a function)

hasOwnProperty

public boolean hasOwnProperty(String propertyName)
Description copied from class: ObjectType
Checks whether the property whose name is given is present directly on the object. Returns false even if it is declared on a supertype.

Overrides:
hasOwnProperty in class ObjectType

isPropertyTypeDeclared

public boolean isPropertyTypeDeclared(String property)
Description copied from class: ObjectType
Checks whether the property's type is declared.

Specified by:
isPropertyTypeDeclared in class ObjectType

isPropertyInExterns

public boolean isPropertyInExterns(String propertyName)
Description copied from class: ObjectType
Checks whether the property was defined in the externs.

Overrides:
isPropertyInExterns in class ObjectType

getPropertyNode

public Node getPropertyNode(String propertyName)
Description copied from class: ObjectType
Gets the node corresponding to the definition of the specified property. This could be the node corresponding to declaration of the property or the node corresponding to the first reference to this property, e.g., "this.propertyName" in a constructor. Note this is mainly intended to be an estimate of where in the source code a property is defined. Sometime the returned node is not even part of the global AST but in the AST of the JsDoc that defines a type.

Overrides:
getPropertyNode in class ObjectType
Parameters:
propertyName - the name of the property
Returns:
the Node corresponding to the property or null.

unboxesTo

public JSType unboxesTo()
Description copied from class: JSType
Gets the type to which this type unboxes.

Overrides:
unboxesTo in class JSType
Returns:
the unboxed type or null if this type does not unbox.

hasReferenceName

public boolean hasReferenceName()
Description copied from class: ObjectType
Returns true if the object is named.

Overrides:
hasReferenceName in class ObjectType
Returns:
true if the object is named, false if it is anonymous

isNativeObjectType

public boolean isNativeObjectType()
Whether this is a built-in object.

Overrides:
isNativeObjectType in class ObjectType

getOwnerFunction

public FunctionType getOwnerFunction()
Description copied from class: ObjectType
Gets the owner of this if it's a function prototype.

Overrides:
getOwnerFunction in class ObjectType

getCtorImplementedInterfaces

public Iterable<ObjectType> getCtorImplementedInterfaces()
Description copied from class: ObjectType
Gets the interfaces implemented by the ctor associated with this type. Intended to be overridden by subclasses.

Overrides:
getCtorImplementedInterfaces in class ObjectType

getCtorExtendedInterfaces

public Iterable<ObjectType> getCtorExtendedInterfaces()
Description copied from class: ObjectType
Gets the interfaces extended by the interface associated with this type. Intended to be overriden by subclasses.

Overrides:
getCtorExtendedInterfaces in class ObjectType

matchConstraint

public void matchConstraint(ObjectType constraintObj)
Description copied from class: JSType
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 contraint (much like how the java compiler does reverse-inference to figure out generics).

Overrides:
matchConstraint in class JSType