javafe.tc
Class EnvForLocals

java.lang.Object
  javafe.tc.Env
      javafe.tc.EnvForLocals

All Implemented Interfaces:

java.lang.Cloneable

public class EnvForLocals

extends Env

implements java.lang.Cloneable

EnvForLocals are used to extend an existing Env with one new local binding, either a local variable definition or a formal parameter.

See EnvForLocalType for how to extend an existing Env with one new local type binding.

Field Summary

protected GenericVarDecl	decl The new local binding.
protected Env	parent Our parent environment

Fields inherited from class javafe.tc.Env

prefixSize, typeEnv, whereDecoration

Constructor Summary

EnvForLocals(Env parent, GenericVarDecl decl)
Create a environment from an existing one by adding a new local binding.

EnvForLocals(Env parent, GenericVarDecl decl, boolean warnAboutDuplication)

Method Summary

Env	asStaticContext() Returns a new Env that acts the same as us, except that its current instance (if any) is not accessible.
void	display() Display information about us to System.out.
TypeSig	getEnclosingClass() Return the intermost class enclosing the code that is checked in this environment.
TypeSig	getEnclosingInstance() If there is an enclosing instance in scope, then return the (exact) type of the innermost such instance.
boolean	isDuplicate(Identifier id)
boolean	isStaticContext() Is there a current instance in scope?
ASTNode	locateFieldOrLocal(Identifier id) Locate the lexically innermost field or local variable declaration.
TypeSig	locateMethod(Identifier id) Locate the lexically innermost method named id.
TypeSig	lookupSimpleTypeName(TypeSig caller, Identifier id, int loc) Attempt to lookup a simple TypeName in this environment to get the TypeSig it denotes.

Methods inherited from class javafe.tc.Env

canAccessInstance, disambiguateExprName, disambiguateMethodName, disambiguateTypeOrFieldName, findTypeNamePrefix, getInferredThisExpr, getInnermostInstance, getObjectDesignator, lookupEnclosingInstance, lookupTypeName, processTypeNameAnnotations, resolveType, resolveTypeName, whereDeclared

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

parent

protected Env parent

Our parent environment

decl

protected GenericVarDecl decl

The new local binding.

Constructor Detail

EnvForLocals

public EnvForLocals(Env parent,
                    GenericVarDecl decl)

Create a environment from an existing one by adding a new local binding.

We report an error to ErrorSet if the new local binding is a redefinition of a local binding not hidden by a field.

EnvForLocals

public EnvForLocals(Env parent,
                    GenericVarDecl decl,
                    boolean warnAboutDuplication)

Method Detail

isStaticContext

public boolean isStaticContext()

Is there a current instance in scope?

E.g., is "this" (or ".this") legal here?

This is also refered to as "are we in a static context?". The legality of super also depends on this result.

The legality of C.this, C != is different; see canAccessInstance(-).

Specified by:

isStaticContext in class Env

getEnclosingClass

public TypeSig getEnclosingClass()

Return the intermost class enclosing the code that is checked in this environment.

May return null if there is no enclosing class (aka, for environments for CompilationUnits).

If isStaticContext() returns true, then this is the type of "this".

Specified by:

getEnclosingClass in class Env

getEnclosingInstance

public TypeSig getEnclosingInstance()

If there is an enclosing instance in scope, then return the (exact) type of the innermost such instance.

Note: this is considered a current instance, not an enclosing instance, even inside its methods.

Specified by:

getEnclosingInstance in class Env

asStaticContext

public Env asStaticContext()

Returns a new Env that acts the same as us, except that its current instance (if any) is not accessible.

Note: this routine is somewhat inefficient and should be avoided unless an unknown environment needs to be coerced in this way.

Specified by:

asStaticContext in class Env

lookupSimpleTypeName

public TypeSig lookupSimpleTypeName(TypeSig caller,
                                    Identifier id,
                                    int loc)

Attempt to lookup a simple TypeName in this environment to get the TypeSig it denotes. Returns null if no such type exists.

This routine does not check that the resulting type (if any) is actually accessable.

If id is ambiguous, then if loc != Location.NULL then a fatal error is reported at that location via ErrorSet else one of its possible meanings is returned.

Specified by:

lookupSimpleTypeName in class Env

locateFieldOrLocal

public ASTNode locateFieldOrLocal(Identifier id)

Locate the lexically innermost field or local variable declaration.

Let d be the lexically innermost field or local variable declaration (including formals) of id (if any such declaration exists). Then this routine returns:

d (a LocalVarDecl or FormalParaDecl) if d is a local variable declaration the class C that lexically encloses us and contains the (inherited) field d if d is a field declaration null if d does not exist Note: inherited fields are considered to lexically enclose the code of their subclasses. We give the class containing the field instead of the field itself to postpone dealing with multiple fields named id visible in the same class.

In the field case, id disambiguates to C[.this].id.

Specified by:

locateFieldOrLocal in class Env

isDuplicate

public boolean isDuplicate(Identifier id)

Overrides:

isDuplicate in class Env

locateMethod

public TypeSig locateMethod(Identifier id)

Locate the lexically innermost method named id.

Returns the TypeSig for the innermost lexically enclosing type that has a method named id or null if no such type exists.

Note: inherited methods are considered to lexically enclose the code of their subclasses.

id disambiguates to C[.this].id.

Specified by:

locateMethod in class Env

display

public void display()

Display information about us to System.out. This function is intended only for debugging use.

Specified by:

display in class Env