jif.types.principal
Class DynamicPrincipal_c

java.lang.Object
  polyglot.types.TypeObject_c
      jif.types.principal.Principal_c
          jif.types.principal.DynamicPrincipal_c

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Param, DynamicPrincipal, Principal, polyglot.types.TypeObject, polyglot.util.Copy

public class DynamicPrincipal_c
extends Principal_c
implements DynamicPrincipal

An implementation of the DynamicPrincipal interface.

See Also:

Serialized Form

Field Summary

Fields inherited from class jif.types.principal.Principal_c

variables

Fields inherited from class polyglot.types.TypeObject_c

position, ts

Constructor Summary

DynamicPrincipal_c(AccessPath path, JifTypeSystem ts, polyglot.util.Position pos, PrincipalToJavaExpr toJava)

Method Summary

boolean	equalsImpl(polyglot.types.TypeObject o)
int	hashCode()
boolean	isCanonical()
boolean	isRuntimeRepresentable()
PathMap	labelCheck(JifContext A, LabelChecker lc) Label check the principal, which will determine how much information may be gained if the principal is evaluated at runtime.
AccessPath	path()
Principal	subst(LabelSubstitution substitution)
java.util.List	throwTypes(polyglot.types.TypeSystem ts) If the principal is runtime representable, when it is evaluated at runtime it may throw exceptions.
java.lang.String	toString()

Methods inherited from class jif.types.principal.Principal_c

hasVariables, isBottomPrincipal, isTopPrincipal, simplify, toJava, variables

Methods inherited from class polyglot.types.TypeObject_c

copy, equals, position, typeSystem

Methods inherited from class java.lang.Object

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

Methods inherited from interface jif.types.principal.Principal

hasVariables, isBottomPrincipal, isTopPrincipal, simplify, toJava, variables

Methods inherited from interface polyglot.types.TypeObject

position, typeSystem

Methods inherited from interface polyglot.util.Copy

copy

Constructor Detail

DynamicPrincipal_c

public DynamicPrincipal_c(AccessPath path,
                          JifTypeSystem ts,
                          polyglot.util.Position pos,
                          PrincipalToJavaExpr toJava)

Method Detail

path

public AccessPath path()

Specified by:

path in interface DynamicPrincipal

isRuntimeRepresentable

public boolean isRuntimeRepresentable()

Specified by:

isRuntimeRepresentable in interface Param

Specified by:

isRuntimeRepresentable in class Principal_c

isCanonical

public boolean isCanonical()

Specified by:

isCanonical in interface Param

Specified by:

isCanonical in interface polyglot.types.TypeObject

Specified by:

isCanonical in class Principal_c

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

equalsImpl

public boolean equalsImpl(polyglot.types.TypeObject o)

Specified by:

equalsImpl in interface polyglot.types.TypeObject

Specified by:

equalsImpl in class Principal_c

hashCode

public int hashCode()

Specified by:

hashCode in class Principal_c

throwTypes

public java.util.List throwTypes(polyglot.types.TypeSystem ts)

Description copied from interface: Principal

If the principal is runtime representable, when it is evaluated at runtime it may throw exceptions. This method returns a list of the exceptions that the runtime evaluation of the principal may produce. If the principal cannot be evaluated at runtime, an empty list should be returned.

Specified by:

throwTypes in interface Principal

Overrides:

throwTypes in class Principal_c

subst

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

Specified by:

subst in interface Principal

Overrides:

subst in class Principal_c

Parameters:

substitution - The LabelSubstitution to apply to this principal

Returns:

the result of applying labelSubst to this principal.

Throws:

polyglot.types.SemanticException

labelCheck

public PathMap labelCheck(JifContext A,
                          LabelChecker lc)

Description copied from interface: Principal

Label check the principal, which will determine how much information may be gained if the principal is evaluated at runtime. For example, given the dynamic principal p, where p is a local variable, evaluation of this label at runtime will reveal as much information as the label of p. For example, the following code is illegal, as the runtime evaluation of the principal reveals too much information

 boolean{Alice:} secret = ...;
 final principal{Alice:} p = secret?Bob:Chuck;
 boolean{} leak = false;
 if (p actsfor Bob) { // evaluation of p reveals
                      // information at level {Alice:}
     leak = true;
        } 
 

Specified by:

labelCheck in interface Principal

Overrides:

labelCheck in class Principal_c

See Also:

Jif.labelCheck(LabelChecker), Label.labelCheck(JifContext, LabelChecker)