Class UnionType

  • All Implemented Interfaces:
    java.lang.Cloneable, Type

    public class UnionType
    extends AssociativeType
    implements java.lang.Cloneable
    A class representing the type of a UnionToken. To set the type of a typeable object (such as a port or parameter) to a union with particular fields, create an instance of this class and call setTypeEquals() with that instance as an argument.

    The depth subtyping is similar to that of RecordTypes. However, the width subtyping for UnionType is opposite compared to RecordType i.e., a UnionType with more fields is a supertype of a UnionType with a subset of the fields. For example, {|x = double, y = int} is a supertype of {|x = double}.

    Since:
    Ptolemy II 5.2
    Version:
    $Id$
    Author:
    Yuhong Xiong, Elaine Cheong and Steve Neuendorffer
    Pt.AcceptedRating:
    Red (cxh)
    Pt.ProposedRating:
    Red (yuhongx)
    • Constructor Summary

      Constructors 
      Constructor Description
      UnionType​(java.lang.String[] labels, Type[] types)
      Construct a new UnionType with the specified labels and types.
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected int _compare​(StructuredType type)
      Compare this type with the specified type.
      protected StructuredType _getRepresentative()
      Return a static instance of RecordType.
      protected StructuredType _greatestLowerBound​(StructuredType type)
      Return the greatest lower bound of this type with the specified type.
      protected StructuredType _leastUpperBound​(StructuredType type)
      Return the least Upper bound of this type with the specified type.
      java.lang.Object clone()
      Return a deep copy of this UnionType if it is a variable, or itself if it is a constant.
      Token convert​(Token token)
      Convert the argument token into a UnionToken having this type, if lossless conversion can be done.
      int depth()
      Return the depth of a union type.
      boolean equals​(java.lang.Object object)
      Determine if the argument represents the same UnionType as this object.
      Type get​(java.lang.String label)
      Return the type of the specified label.
      java.lang.Class getTokenClass()
      Return the class for tokens that this type represents.
      InequalityTerm getTypeTerm​(java.lang.String label)
      Return the InequalityTerm representing the type of the specified label.
      int hashCode()
      Return a hash code value for this object.
      void initialize​(Type type)
      Set the elements that have declared type BaseType.UNKNOWN (the leaf type variable) to the specified type.
      boolean isAbstract()
      Test if this type corresponds to an abstract token class.
      boolean isCompatible​(Type type)
      Test if the argument type is compatible with this type.
      boolean isConstant()
      Test if this UnionType is a constant.
      boolean isInstantiable()
      Test if this type corresponds to an instantiable token class.
      boolean isSubstitutionInstance​(Type type)
      Test if the specified type is a substitution instance of this type.
      java.util.Set labelSet()
      Return the labels of this record type as a Set.
      java.lang.String toString()
      Return the string representation of this type.
      void updateType​(StructuredType newType)
      Update this Type to the specified UnionType.
      • Methods inherited from class java.lang.Object

        finalize, getClass, notify, notifyAll, wait, wait, wait
    • Constructor Detail

      • UnionType

        public UnionType​(java.lang.String[] labels,
                         Type[] types)
        Construct a new UnionType with the specified labels and types. To leave the types of some fields undeclared, use BaseType.UNKNOWN. The labels and the types are specified in two arrays. These two arrays must have the same length, and their elements have one to one correspondence. That is, the i'th entry in the types array is the type for the i'th label in the labels array. To construct the empty record type, set the length of the argument arrays to 0.
        Parameters:
        labels - An array of String.
        types - An array of Type.
        Throws:
        java.lang.IllegalArgumentException - If the two arrays do not have the same size.
        java.lang.NullPointerException - If one of the arguments is null.
    • Method Detail

      • clone

        public java.lang.Object clone()
        Return a deep copy of this UnionType if it is a variable, or itself if it is a constant.
        Specified by:
        clone in interface Type
        Specified by:
        clone in class StructuredType
        Returns:
        A UnionType.
      • convert

        public Token convert​(Token token)
                      throws IllegalActionException
        Convert the argument token into a UnionToken having this type, if lossless conversion can be done. The argument must be a UnionToken, and its type must be a subtype of this record type. The argument token must have at least the fields of this type. Extra fields in the argument token that are not in this type are removed.
        Specified by:
        convert in interface Type
        Parameters:
        token - A token.
        Returns:
        An UnionToken.
        Throws:
        IllegalActionException - If lossless conversion cannot be done.
      • depth

        public int depth()
        Return the depth of a union type. The depth of a union type is the number of times it contains other structured types.
        Overrides:
        depth in class StructuredType
        Returns:
        the depth of a union type.
      • equals

        public boolean equals​(java.lang.Object object)
        Determine if the argument represents the same UnionType as this object. Two record types are equal if they have the same field names and the type of each field is the same.
        Specified by:
        equals in interface Type
        Overrides:
        equals in class java.lang.Object
        Parameters:
        object - Another object.
        Returns:
        True if the argument represents the same UnionType as this object.
      • get

        public Type get​(java.lang.String label)
        Return the type of the specified label. If this type does not contain the specified label, return null.
        Specified by:
        get in class AssociativeType
        Parameters:
        label - The specified label.
        Returns:
        a Type.
      • getTokenClass

        public java.lang.Class getTokenClass()
        Return the class for tokens that this type represents.
        Specified by:
        getTokenClass in interface Type
        Returns:
        The class for tokens that this type represents.
      • getTypeTerm

        public InequalityTerm getTypeTerm​(java.lang.String label)
        Return the InequalityTerm representing the type of the specified label.
        Parameters:
        label - The specified label.
        Returns:
        An InequalityTerm.
        See Also:
        InequalityTerm
      • hashCode

        public int hashCode()
        Return a hash code value for this object.
        Overrides:
        hashCode in class java.lang.Object
      • initialize

        public void initialize​(Type type)
        Set the elements that have declared type BaseType.UNKNOWN (the leaf type variable) to the specified type.
        Specified by:
        initialize in class StructuredType
        Parameters:
        type - the type to set the leaf type variable to.
      • isAbstract

        public boolean isAbstract()
        Test if this type corresponds to an abstract token class. A UnionType is abstract if any field is abstract
        Specified by:
        isAbstract in interface Type
        Overrides:
        isAbstract in class StructuredType
        Returns:
        True if this type is instantiable.
      • isCompatible

        public boolean isCompatible​(Type type)
        Test if the argument type is compatible with this type. The given type will be compatible with this type if it is BaseType.UNKNOWN, or a UnionType that contains at most as many fields.
        Specified by:
        isCompatible in interface Type
        Parameters:
        type - An instance of Type.
        Returns:
        True if the argument is compatible with this type.
      • isConstant

        public boolean isConstant()
        Test if this UnionType is a constant. A UnionType is a constant if the declared type of all of its fields are constant.
        Specified by:
        isConstant in interface Type
        Returns:
        True if this type is a constant.
      • isInstantiable

        public boolean isInstantiable()
        Test if this type corresponds to an instantiable token class. A UnionType is instantiable if all of its fields are instantiable.
        Specified by:
        isInstantiable in interface Type
        Returns:
        True if this type is instantiable.
      • isSubstitutionInstance

        public boolean isSubstitutionInstance​(Type type)
        Test if the specified type is a substitution instance of this type. One union is a substitution instance of another if they have fields with the same names and each field of the given type is a substitution instance of the corresponding field in this type.
        Specified by:
        isSubstitutionInstance in interface Type
        Parameters:
        type - A Type.
        Returns:
        True if the argument is a substitution instance of this type.
        See Also:
        Type.isSubstitutionInstance(ptolemy.data.type.Type)
      • labelSet

        public java.util.Set labelSet()
        Return the labels of this record type as a Set.
        Returns:
        A Set containing strings.
      • toString

        public java.lang.String toString()
        Return the string representation of this type. The format is {|label = type, label = type, ...|}. The record fields are listed in the lexicographical order of the labels determined by the java.lang.String.compareTo() method.
        Specified by:
        toString in interface Type
        Overrides:
        toString in class java.lang.Object
        Returns:
        A String.
      • updateType

        public void updateType​(StructuredType newType)
                        throws IllegalActionException
        Update this Type to the specified UnionType. The specified type must be a UnionType and have the same structure as this one. This method will only update the component whose declared type is BaseType.UNKNOWN, and leave the constant part of this type intact.
        Overrides:
        updateType in class StructuredType
        Parameters:
        newType - A StructuredType.
        Throws:
        IllegalActionException - If the specified type is not a UnionType or it does not have the same structure as this one.
      • _compare

        protected int _compare​(StructuredType type)
        Compare this type with the specified type. The specified type must be a UnionType, otherwise an exception will be thrown. This method returns one of ptolemy.graph.CPO.LOWER, ptolemy.graph.CPO.SAME, ptolemy.graph.CPO.HIGHER, ptolemy.graph.CPO.INCOMPARABLE, indicating this type is lower than, equal to, higher than, or incomparable with the specified type in the type hierarchy, respectively.
        Specified by:
        _compare in class StructuredType
        Parameters:
        type - a UnionType.
        Returns:
        An integer.
        Throws:
        java.lang.IllegalArgumentException - If the specified type is not a UnionType.
      • _greatestLowerBound

        protected StructuredType _greatestLowerBound​(StructuredType type)
        Return the greatest lower bound of this type with the specified type. The specified type must be a UnionType, otherwise an exception will be thrown.
        Specified by:
        _greatestLowerBound in class StructuredType
        Parameters:
        type - a UnionType.
        Returns:
        a UnionType.
        Throws:
        java.lang.IllegalArgumentException - If the specified type is not a UnionType.
      • _leastUpperBound

        protected StructuredType _leastUpperBound​(StructuredType type)
        Return the least Upper bound of this type with the specified type. The specified type must be a UnionType, otherwise an exception will be thrown.
        Specified by:
        _leastUpperBound in class StructuredType
        Parameters:
        type - a UnionType.
        Returns:
        a UnionType.
        Throws:
        java.lang.IllegalArgumentException - If the specified type is not a UnionType.