Package org.checkerframework.framework.util.typeinference8.types

Class CaptureVariable

java.lang.Object

org.checkerframework.framework.util.typeinference8.types.Variable

org.checkerframework.framework.util.typeinference8.types.CaptureVariable

@Interned
public class CaptureVariable
extends Variable

Variables created as a part of a capture bound.

Field Summary

Fields inherited from class org.checkerframework.framework.util.typeinference8.types.Variable

context, id, invocation, map, typeVariable, typeVariableJava, variableBounds

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
@Nullable ConstraintSet	getWildcardConstraints(AbstractType Ai, AbstractType Bi)	Returns the constraints generated when incorporating a capture bound, or null if the incorporation implies the bound false.
boolean	isCapturedWildcard()	Returns true if this variable was created for a capture bound and the type argument it captures is a wildcard.
boolean	isCaptureVariable()	Returns true if this variable was created for a capture bound.
void	setCapturedWildcard(boolean capturedWildcard)	Sets whether the type argument that this variable captures is a wildcard.
String	toString()

Methods inherited from class org.checkerframework.framework.util.typeinference8.types.Variable

getBounds, getInstantiation, getInvocation, getJavaType, hashCode, initialBounds, restore, save

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Details

toString

public String toString()

Overrides:

toString in class Variable

getWildcardConstraints

public @Nullable ConstraintSet getWildcardConstraints(AbstractType Ai,
 AbstractType Bi)

Returns the constraints generated when incorporating a capture bound, or null if the incorporation implies the bound false. See JLS 18.3.2.

Parameters:

Ai - the captured type argument

Bi - the bound of the type variable

Returns:

constraints generated when incorporating a capture bound, or null if the bound false is implied

equals

public boolean equals(Object o)

Two capture variables are equal only if they are the same object. Every capture bound introduces fresh capture variables (see JLS 18.3.2), and the mapping created by InferenceFactory.createThetaForCapture(com.sun.source.tree.ExpressionTree, org.checkerframework.framework.util.typeinference8.types.AbstractType) is not cached, so two capture bounds for the same invocation create distinct capture variables for the same type variable. Those variables stand for different types, so Variable.equals(java.lang.Object), which compares the type variable and the invocation, must not be used for them. Reference equality is also what the @Interned annotation on this class requires.

Variable.hashCode() is still correct for capture variables: it may return the same value for two capture variables that are not equal, which is permitted.

Overrides:

equals in class Variable

setCapturedWildcard

public void setCapturedWildcard(boolean capturedWildcard)

Sets whether the type argument that this variable captures is a wildcard.

Parameters:

capturedWildcard - true if the captured type argument is a wildcard

isCaptureVariable

public boolean isCaptureVariable()

Description copied from class: Variable

Returns true if this variable was created for a capture bound.

Overrides:

isCaptureVariable in class Variable

Returns:

true if this variable was created for a capture bound

isCapturedWildcard

public boolean isCapturedWildcard()

Description copied from class: Variable

Returns true if this variable was created for a capture bound and the type argument it captures is a wildcard.

Overrides:

isCapturedWildcard in class Variable

Returns:

true if this variable was created for a captured wildcard