Class DefaultTypeCheckingExtension
java.lang.Object
org.codehaus.groovy.transform.stc.TypeCheckingExtension
org.codehaus.groovy.transform.stc.DefaultTypeCheckingExtension
The default type checking handler is used by the standard type checker and doesn't handle
 any of the type checking errors by default. This just means that whenever a type checking
 error is detected, there's no additional information available to the type checker that
 could help it.
 The default handler is also capable of handling a collection of delegate handlers. If a list
 of delegates is set, then the type checker will try all the delegates until one is capable
 of handling an error.
- Since:
- 2.1.0
- 
Field SummaryFieldsFields inherited from class org.codehaus.groovy.transform.stc.TypeCheckingExtensiontypeCheckingVisitor
- 
Constructor SummaryConstructors
- 
Method SummaryModifier and TypeMethodDescriptionvoidaddHandler(TypeCheckingExtension handler) voidafterMethodCall(MethodCall call) Allows the extension to perform additional tasks after the type checker actually visits a method call.voidafterVisitClass(ClassNode node) Allows the extension to perform additional tasks after the type checker actually visited a class node.voidafterVisitMethod(MethodNode node) Allows the extension to perform additional tasks after the type checker actually visited a method node.booleanbeforeMethodCall(MethodCall call) Allows the extension to perform additional tasks before the type checker actually visits a method call.booleanbeforeVisitClass(ClassNode node) Allows the extension to perform additional tasks before the type checker actually visits a class node.booleanbeforeVisitMethod(MethodNode node) Allows the extension to perform additional tasks before the type checker actually visits a method node.voidfinish()Subclasses should implement this method if they need to perform additional checks after the type checker has finished its work.handleAmbiguousMethods(List<MethodNode> nodes, Expression origin) This method is called by the type checker before throwing an "ambiguous method" error, giving the chance to the extension to select the method properly.booleanhandleIncompatibleAssignment(ClassNode lhsType, ClassNode rhsType, Expression assignmentExpression) This method is called by the type checker when an assignment is not allowed by the type checker.booleanhandleIncompatibleReturnType(ReturnStatement returnStatement, ClassNode inferredReturnType) Allows the extension to catch incompatible return types.handleMissingMethod(ClassNode receiver, String name, ArgumentListExpression argumentList, ClassNode[] argumentTypes, MethodCall call) This method is called by the type checker when a method call cannot be resolved.booleanThis method is called by the type checker when an attribute expression cannot be resolved (for example, when an attribute doesn't exist).booleanThis method is called by the type checker when a property expression cannot be resolved (for example, when a property doesn't exist).booleanThis method is called by the type checker when a variable expression cannot be resolved.voidonMethodSelection(Expression expression, MethodNode target) Allows the extension to listen to method selection events.voidremoveHandler(TypeCheckingExtension handler) voidsetup()Subclasses should implement this method whenever they need to perform special checks before the type checker starts working.Methods inherited from class org.codehaus.groovy.transform.stc.TypeCheckingExtensionaddStaticTypeError, buildListType, buildMapType, classNodeFor, classNodeFor, existsProperty, existsProperty, extractStaticReceiver, getArgumentTypes, getTargetMethod, getType, isStaticMethodCallOnClass, lookupClassNodeFor, parameterizedType, storeType
- 
Field Details- 
handlers
 
- 
- 
Constructor Details- 
DefaultTypeCheckingExtension
 
- 
- 
Method Details- 
addHandler
- 
removeHandler
- 
handleUnresolvedVariableExpressionDescription copied from class:TypeCheckingExtensionThis method is called by the type checker when a variable expression cannot be resolved. It gives the extension a chance to resolve it for the type checker.- Overrides:
- handleUnresolvedVariableExpressionin class- TypeCheckingExtension
- Parameters:
- vexp- the unresolved variable extension
- Returns:
- booleanfalse if the extension doesn't handle it, true if the extension handles this variable.
 
- 
handleUnresolvedPropertyDescription copied from class:TypeCheckingExtensionThis method is called by the type checker when a property expression cannot be resolved (for example, when a property doesn't exist). It gives the extension a chance to resolve it.- Overrides:
- handleUnresolvedPropertyin class- TypeCheckingExtension
- Parameters:
- pexp- the unresolved property
- Returns:
- booleanfalse if this extension doesn't resolve the property, true if it resolves the property.
 
- 
handleUnresolvedAttributeDescription copied from class:TypeCheckingExtensionThis method is called by the type checker when an attribute expression cannot be resolved (for example, when an attribute doesn't exist). It gives the extension a chance to resolve it.- Overrides:
- handleUnresolvedAttributein class- TypeCheckingExtension
- Parameters:
- aexp- the unresolved attribute
- Returns:
- booleanfalse if this extension doesn't resolve the attribute, true if it resolves the attribute.
 
- 
handleIncompatibleAssignmentpublic boolean handleIncompatibleAssignment(ClassNode lhsType, ClassNode rhsType, Expression assignmentExpression) Description copied from class:TypeCheckingExtensionThis method is called by the type checker when an assignment is not allowed by the type checker. Extensions may override this method to allow such assignments where the type checker normally disallows them.- Overrides:
- handleIncompatibleAssignmentin class- TypeCheckingExtension
- Parameters:
- lhsType- the type of the left hand side of the assignment, as found by the type checker
- rhsType- the type of the right hand side of the assignment, as found by the type checker
- assignmentExpression- the assignment expression which triggered this call
- Returns:
- booleanfalse if the extension does not handle this assignment, true otherwise
 
- 
handleIncompatibleReturnTypepublic boolean handleIncompatibleReturnType(ReturnStatement returnStatement, ClassNode inferredReturnType) Description copied from class:TypeCheckingExtensionAllows the extension to catch incompatible return types. This event is called whenever the type checker finds that an inferred return type is incompatible with the declared return type of a method.- Overrides:
- handleIncompatibleReturnTypein class- TypeCheckingExtension
- Parameters:
- returnStatement- the statement that triggered the error
- inferredReturnType- the inferred return type for this statement
- Returns:
- false if the extension doesn't handle the error, true otherwise
 
- 
handleAmbiguousMethodsDescription copied from class:TypeCheckingExtensionThis method is called by the type checker before throwing an "ambiguous method" error, giving the chance to the extension to select the method properly. This means that when this method is called, the "nodes" parameter contains at least two methods. If the returned list still contains at least two methods, then the type checker will throw an ambiguous method call error. If the returned method contains 1 element, then the type checker will not throw any error. It is invalid to return an empty list.- Overrides:
- handleAmbiguousMethodsin class- TypeCheckingExtension
- Parameters:
- nodes- the list of ambiguous methods
- origin- the expression which originated the method selection process
- Returns:
- a single element list of disambiguated selection, or more elements if still ambiguous. It is not allowed to return an empty list.
 
- 
handleMissingMethodpublic List<MethodNode> handleMissingMethod(ClassNode receiver, String name, ArgumentListExpression argumentList, ClassNode[] argumentTypes, MethodCall call) Description copied from class:TypeCheckingExtensionThis method is called by the type checker when a method call cannot be resolved. Extensions may override this method to handle missing methods and prevent the type checker from throwing an error.- Overrides:
- handleMissingMethodin class- TypeCheckingExtension
- Parameters:
- receiver- the type of the receiver
- name- the name of the called method
- argumentList- the list of arguments of the call
- argumentTypes- the types of the arguments of the call
- call- the method call itself, if needed
- Returns:
- an empty list if the extension cannot resolve the method, or a list of potential methods if the extension finds candidates. This method must not return null.
 
- 
afterVisitMethodDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks after the type checker actually visited a method node. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- afterVisitMethodin class- TypeCheckingExtension
- Parameters:
- node- a method node
 
- 
beforeVisitMethodDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks before the type checker actually visits a method node. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- beforeVisitMethodin class- TypeCheckingExtension
- Parameters:
- node- a method node
- Returns:
- false if the type checker should visit the node, or true if this extension replaces what the type checker would do with the method.
 
- 
afterVisitClassDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks after the type checker actually visited a class node. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- afterVisitClassin class- TypeCheckingExtension
- Parameters:
- node- a class node
 
- 
beforeVisitClassDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks before the type checker actually visits a class node. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- beforeVisitClassin class- TypeCheckingExtension
- Parameters:
- node- a class node
- Returns:
- false if the type checker should visit the node, or true if this extension replaces what the type checker would do with the class.
 
- 
afterMethodCallDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks after the type checker actually visits a method call. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- afterMethodCallin class- TypeCheckingExtension
- Parameters:
- call- a method call, either a- MethodCallExpression,- StaticMethodCallExpression, or- ConstructorCallExpression
 
- 
beforeMethodCallDescription copied from class:TypeCheckingExtensionAllows the extension to perform additional tasks before the type checker actually visits a method call. Compared to a custom visitor, this method ensures that the node being visited is a node which would have been visited by the type checker. This is in particular important for nodes which are marked withTypeCheckingMode.SKIP.- Overrides:
- beforeMethodCallin class- TypeCheckingExtension
- Parameters:
- call- a method call, either a- MethodCallExpression,- StaticMethodCallExpression, or- ConstructorCallExpression
- Returns:
- false if the type checker should visit the node, or true if this extension replaces what the type checker would do with the method call.
 
- 
onMethodSelectionDescription copied from class:TypeCheckingExtensionAllows the extension to listen to method selection events. Given an expression, which may be a method call expression, a static method call expression, a pre/postfix expression, ..., if a corresponding method is found, this method is called.- Overrides:
- onMethodSelectionin class- TypeCheckingExtension
- Parameters:
- expression- the expression for which a corresponding method has been found
- target- the method which has been chosen by the type checker
 
- 
setuppublic void setup()Description copied from class:TypeCheckingExtensionSubclasses should implement this method whenever they need to perform special checks before the type checker starts working.- Overrides:
- setupin class- TypeCheckingExtension
 
- 
finishpublic void finish()Description copied from class:TypeCheckingExtensionSubclasses should implement this method if they need to perform additional checks after the type checker has finished its work. This is particularly useful for situations where you need multiple passes. Some checks in that case may be deferred to the end, using this method.- Overrides:
- finishin class- TypeCheckingExtension
 
 
-