org.checkerframework.framework.type.visitor

Class AnnotatedTypeScanner<R,P>

java.lang.Object

org.checkerframework.framework.type.visitor.AnnotatedTypeScanner<R,P>

Type Parameters:

R - the return type of this visitor's methods. Use Void for visitors that do not need to return results.

P - the type of the additional parameter to this visitor's methods. Use Void for visitors that do not need an additional parameter.

All Implemented Interfaces:

AnnotatedTypeVisitor<R,P>

Direct Known Subclasses:

AnnotatedTypeComparer, AnnotatedTypeFactory.InheritedFromClassAnnotator, BaseTypeValidator, HashcodeAtmVisitor, SimpleAnnotatedTypeScanner, TypeAnnotator

public class AnnotatedTypeScanner<R,P>
extends Object
implements AnnotatedTypeVisitor<R,P>

A TypeVisitor that visits all the child tree nodes. To visit types of a particular type, just override the corresponding visitXYZ method. Inside your method, call super.visitXYZ to visit descendant nodes.

The default implementation of the visitXYZ methods will determine a result as follows:

• If the node being visited has no children, the result will be null.
• If the node being visited has one child, the result will be the result of calling scan on that child. The child may be a simple node or itself a list of nodes.
• If the node being visited has more than one child, the result will be determined by calling scan each child in turn, and then combining the result of each scan after the first with the cumulative result so far, as determined by the reduce(R, R) method. Each child may be either a simple node or a list of nodes. The default behavior of the reduce method is such that the result of the visitXYZ method will be the result of the last child scanned.

Here is an example to count the parameter types number of nodes in a tree:

 class CountTypeVariable extends TreeScanner {

     @Override
     public Integer visitTypeVariable(ATypeVariable node, Void p) {
         return 1;
     }

     @Override
     public Integer reduce(Integer r1, Integer r2) {
         return (r1 == null ? 0 : r1) + (r2 == null ? 0 : r2);
     }
 }
 

Field Summary

Fields

Modifier and Type	Field and Description
protected Map<AnnotatedTypeMirror,R>	visitedNodes

Constructor Summary

Constructors

Constructor and Description
AnnotatedTypeScanner()

Method Summary

Modifier and Type	Method and Description
protected R	reduce(R r1, R r2) Combines r1 and r2 and returns the result.
void	reset() Reset the scanner to allow reuse of the same instance.
protected R	scan(AnnotatedTypeMirror type, P p) Scan type by calling type.accept(this, p); this method may be overridden by subclasses.
protected R	scan(Iterable<? extends AnnotatedTypeMirror> types, P p) Scan all the types and returns the reduced result.
protected R	scanAndReduce(AnnotatedTypeMirror type, P p, R r) Scans type with the parameter p and reduces the result with r.
protected R	scanAndReduce(Iterable<? extends AnnotatedTypeMirror> types, P p, R r)
R	visit(AnnotatedTypeMirror type) Calls reset() and then scans type using null as the parameter.
R	visit(AnnotatedTypeMirror type, P p) Calls reset() and then scans type using p as the parameter.
R	visitArray(AnnotatedTypeMirror.AnnotatedArrayType type, P p) Visits an array type.
R	visitDeclared(AnnotatedTypeMirror.AnnotatedDeclaredType type, P p) Visits a declared type.
R	visitExecutable(AnnotatedTypeMirror.AnnotatedExecutableType type, P p) Visits an executable type.
R	visitIntersection(AnnotatedTypeMirror.AnnotatedIntersectionType type, P p) Visits an intersection type.
R	visitNoType(AnnotatedTypeMirror.AnnotatedNoType type, P p) Visits NoType type.
R	visitNull(AnnotatedTypeMirror.AnnotatedNullType type, P p) Visits a null type.
R	visitPrimitive(AnnotatedTypeMirror.AnnotatedPrimitiveType type, P p) Visits a primitive type.
R	visitTypeVariable(AnnotatedTypeMirror.AnnotatedTypeVariable type, P p) Visits a type variable.
R	visitUnion(AnnotatedTypeMirror.AnnotatedUnionType type, P p) Visits an union type.
R	visitWildcard(AnnotatedTypeMirror.AnnotatedWildcardType type, P p) Visits a wildcard type.

Methods inherited from class java.lang.Object

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

Field Detail

visitedNodes

protected final Map<AnnotatedTypeMirror,R> visitedNodes

Constructor Detail

AnnotatedTypeScanner

public AnnotatedTypeScanner()

Method Detail

reset

public void reset()

Reset the scanner to allow reuse of the same instance. Subclasses should override this method to clear their additional state; they must call the super implementation.

visit

public final R visit(AnnotatedTypeMirror type)

Calls reset() and then scans type using null as the parameter.

Specified by:

visit in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - type to scan

Returns:

result of scanning type

visit

public final R visit(AnnotatedTypeMirror type,
                     P p)

Calls reset() and then scans type using p as the parameter.

Specified by:

visit in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

result of scanning type

scan

protected R scan(AnnotatedTypeMirror type,
                 P p)

Scan type by calling type.accept(this, p); this method may be overridden by subclasses.

Parameters:

type - type to scan

p - the parameter to use

Returns:

the result of visiting type

scan

protected R scan(Iterable<? extends AnnotatedTypeMirror> types,
                 P p)

Scan all the types and returns the reduced result.

Parameters:

types - types to scan

p - the parameter to use

Returns:

the reduced result of scanning all the types

scanAndReduce

protected R scanAndReduce(Iterable<? extends AnnotatedTypeMirror> types,
                          P p,
                          R r)

scanAndReduce

protected R scanAndReduce(AnnotatedTypeMirror type,
                          P p,
                          R r)

Scans type with the parameter p and reduces the result with r.

Parameters:

type - type to scan

p - parameter to use for when scanning type

r - result to combine with the result of scanning type

Returns:

the combination of r with the result of scanning type

reduce

protected R reduce(R r1,
                   R r2)

Combines r1 and r2 and returns the result. The default implementation returns r1 if it is not null; otherwise, it returns r2.

Parameters:

r1 - a result of scan

r2 - a result of scan

Returns:

the combination of r1 and r2

visitDeclared

public R visitDeclared(AnnotatedTypeMirror.AnnotatedDeclaredType type,
                       P p)

Description copied from interface: AnnotatedTypeVisitor

Visits a declared type.

Specified by:

visitDeclared in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitIntersection

public R visitIntersection(AnnotatedTypeMirror.AnnotatedIntersectionType type,
                           P p)

Description copied from interface: AnnotatedTypeVisitor

Visits an intersection type.

Specified by:

visitIntersection in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitUnion

public R visitUnion(AnnotatedTypeMirror.AnnotatedUnionType type,
                    P p)

Description copied from interface: AnnotatedTypeVisitor

Visits an union type.

Specified by:

visitUnion in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitArray

public R visitArray(AnnotatedTypeMirror.AnnotatedArrayType type,
                    P p)

Description copied from interface: AnnotatedTypeVisitor

Visits an array type.

Specified by:

visitArray in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitExecutable

public R visitExecutable(AnnotatedTypeMirror.AnnotatedExecutableType type,
                         P p)

Description copied from interface: AnnotatedTypeVisitor

Visits an executable type.

Specified by:

visitExecutable in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitTypeVariable

public R visitTypeVariable(AnnotatedTypeMirror.AnnotatedTypeVariable type,
                           P p)

Description copied from interface: AnnotatedTypeVisitor

Visits a type variable.

Specified by:

visitTypeVariable in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitNoType

public R visitNoType(AnnotatedTypeMirror.AnnotatedNoType type,
                     P p)

Description copied from interface: AnnotatedTypeVisitor

Visits NoType type.

Specified by:

visitNoType in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitNull

public R visitNull(AnnotatedTypeMirror.AnnotatedNullType type,
                   P p)

Description copied from interface: AnnotatedTypeVisitor

Visits a null type.

Specified by:

visitNull in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitPrimitive

public R visitPrimitive(AnnotatedTypeMirror.AnnotatedPrimitiveType type,
                        P p)

Description copied from interface: AnnotatedTypeVisitor

Visits a primitive type.

Specified by:

visitPrimitive in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result

visitWildcard

public R visitWildcard(AnnotatedTypeMirror.AnnotatedWildcardType type,
                       P p)

Description copied from interface: AnnotatedTypeVisitor

Visits a wildcard type.

Specified by:

visitWildcard in interface AnnotatedTypeVisitor<R,P>

Parameters:

type - the type to visit

p - a visitor-specified parameter

Returns:

a visitor-specified result