jif.types
Class JoinLabel_c

java.lang.Object
  polyglot.ext.jl.types.TypeObject_c
      jif.types.Label_c
          jif.types.JoinLabel_c

All Implemented Interfaces:

java.lang.Cloneable, polyglot.util.Copy, JoinLabel, Label, Param, java.io.Serializable, polyglot.types.TypeObject

public class JoinLabel_c

extends Label_c

implements JoinLabel

An implementation of the JoinLabel interface.

See Also:

Serialized Form

Field Summary

Fields inherited from class polyglot.ext.jl.types.TypeObject_c

position, ts

Constructor Summary

protected	JoinLabel_c()
	JoinLabel_c(JifTypeSystem ts, polyglot.util.Position pos, java.util.Collection components)

Method Summary

Label	bound(VarMap ub, java.util.Set visited) Gets the upper bound of this label.
java.util.Collection	components() Retrieve the collection of components.
JoinLabel	components(java.util.Collection c)
java.lang.String	componentString()
Label	flatten()
Label	fold(UID uid) Substitutes any occurences of for .
boolean	hasVariables() Does this label (or any of its components) contain any label variables?
boolean	isBottom() Is this label equivalent to bottom?
boolean	isCanonical() By default labels are canonical.
boolean	isComparable() Is this label comparable to other labels?
boolean	isCovariant() Is this label covariant?
boolean	isMeetable() Can this label be used in a meet operation with another label?
boolean	isRuntimeRepresentable()
Label	labelOf() Gets labelOf this label.
boolean	leq_(Label L, LabelEnv env) Implementation of leq, should only be called by JifTypeSystem
Label	meet_(Label L, PrincipalHierarchy ph) Implementation of the meet operation, should only be called by JifTypeSystem
Label	minus(Label L) Returns a copy of this Label, with the Label L removed from the components.
Label	simplify() Returns a simplified copy of this Label.
Label	subst(LabelSubstitution substitution) Accepts a LabelSubstitution and returns the result of substituting according to the given LabelSubstitution.
Label	subst(UID uid, Label L) Substitutes any occurences of for L.
void	translate(polyglot.types.Resolver c, polyglot.util.CodeWriter w)
java.util.Collection	variables() The collection of variables contained by this label (or any of its components).

Methods inherited from class jif.types.Label_c

description, description, isEnumerable, isInvariant, isSingleton, isTop, join, join, meet, singletonComponent, toJava, toString

Methods inherited from class polyglot.ext.jl.types.TypeObject_c

copy, equals, equalsImpl, position, typeSystem

Methods inherited from class java.lang.Object

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

Methods inherited from interface jif.types.Label

description, description, isEnumerable, isInvariant, isSingleton, isTop, join, join, meet, singletonComponent, toJava

Methods inherited from interface polyglot.types.TypeObject

equalsImpl, position, typeSystem

Methods inherited from interface polyglot.util.Copy

copy

Constructor Detail

JoinLabel_c

protected JoinLabel_c()

JoinLabel_c

public JoinLabel_c(JifTypeSystem ts,
                   polyglot.util.Position pos,
                   java.util.Collection components)

Method Detail

flatten

public Label flatten()

Specified by:

flatten in interface JoinLabel

minus

public Label minus(Label L)

Description copied from interface: Label

Returns a copy of this Label, with the Label L removed from the components.

Specified by:

minus in interface Label

Overrides:

minus in class Label_c

isBottom

public boolean isBottom()

Description copied from interface: Label

Is this label equivalent to bottom?

For example, a JoinLabel with no components would return true for this method.

Specified by:

isBottom in interface Label

Overrides:

isBottom in class Label_c

isComparable

public boolean isComparable()

Description copied from interface: Label

Is this label comparable to other labels?

For example, an UnknownLabel is not comparable to others, neither is a VarLabel. Most other labels are.

Specified by:

isComparable in interface Label

isMeetable

public boolean isMeetable()

Description copied from interface: Label

Can this label be used in a meet operation with another label?

For example, UnknownLabel returns false. Most other Labels return true.

Specified by:

isMeetable in interface Label

Overrides:

isMeetable in class Label_c

isCanonical

public boolean isCanonical()

Description copied from class: Label_c

By default labels are canonical.

Specified by:

isCanonical in interface Param

Overrides:

isCanonical in class Label_c

isCovariant

public boolean isCovariant()

Description copied from interface: Label

Is this label covariant?

Specified by:

isCovariant in interface Label

Specified by:

isCovariant in class Label_c

Returns:

true iff this label is covariant. A label is covariant if it contains at least one covariant component.

hasVariables

public boolean hasVariables()

Description copied from interface: Label

Does this label (or any of its components) contain any label variables?

Specified by:

hasVariables in interface Label

Overrides:

hasVariables in class Label_c

variables

public java.util.Collection variables()

Description copied from interface: Label

The collection of variables contained by this label (or any of its components).

Specified by:

variables in interface Label

Specified by:

variables in class Label_c

isRuntimeRepresentable

public boolean isRuntimeRepresentable()

Specified by:

isRuntimeRepresentable in interface Param

Specified by:

isRuntimeRepresentable in class Label_c

labelOf

public Label labelOf()

Description copied from interface: Label

Gets labelOf this label. Refer to Andrew's thesis, Figure 5.4

Specified by:

labelOf in interface Label

Specified by:

labelOf in class Label_c

subst

public Label subst(LabelSubstitution substitution)
            throws polyglot.types.SemanticException

Description copied from interface: Label

Accepts a LabelSubstitution and returns the result of substituting according to the given LabelSubstitution.

Specified by:

subst in interface Label

Overrides:

subst in class Label_c

Throws:

polyglot.types.SemanticException

subst

public Label subst(UID uid,
                   Label L)

Description copied from interface: Label

Substitutes any occurences of for L. Refer to Andrew's thesis, Figure 5.5

Specified by:

subst in interface Label

Overrides:

subst in class Label_c

fold

public Label fold(UID uid)

Description copied from interface: Label

Substitutes any occurences of for .

Specified by:

fold in interface Label

Overrides:

fold in class Label_c

components

public JoinLabel components(java.util.Collection c)

components

public java.util.Collection components()

Description copied from interface: Label

Retrieve the collection of components. This method should only be called if isEnumerable returns true. This collection should not be modified.

Specified by:

components in interface Label

Overrides:

components in class Label_c

bound

public Label bound(VarMap ub,
                   java.util.Set visited)

Description copied from interface: Label

Gets the upper bound of this label.

Specified by:

bound in interface Label

Overrides:

bound in class Label_c

leq_

public boolean leq_(Label L,
                    LabelEnv env)

Description copied from interface: Label

Implementation of leq, should only be called by JifTypeSystem

Specified by:

leq_ in interface Label

Specified by:

leq_ in class Label_c

Returns:

true iff ph |- this <= L. Assumes there are no variables in the label.

simplify

public Label simplify()

Description copied from interface: Label

Returns a simplified copy of this Label.

Specified by:

simplify in interface Label

Overrides:

simplify in class Label_c

Returns:

An equivalent label with fewer components by pulling out less restrictive policies.

meet_

public Label meet_(Label L,
                   PrincipalHierarchy ph)

Description copied from interface: Label

Implementation of the meet operation, should only be called by JifTypeSystem

Specified by:

meet_ in interface Label

Specified by:

meet_ in class Label_c

componentString

public java.lang.String componentString()

Specified by:

componentString in interface Label

Specified by:

componentString in class Label_c

translate

public void translate(polyglot.types.Resolver c,
                      polyglot.util.CodeWriter w)

Specified by:

translate in interface Label

Specified by:

translate in class Label_c