Package ptolemy.data.type

Class BaseType

java.lang.Object

ptolemy.data.type.BaseType

All Implemented Interfaces:

Type

Direct Known Subclasses:

BaseType.ArrayBottomType, BaseType.BooleanType, BaseType.ComplexType, BaseType.DateType, BaseType.DoubleType, BaseType.EventType, BaseType.FloatType, BaseType.GeneralType, BaseType.IntType, BaseType.LongType, BaseType.NilType, BaseType.PetiteType, BaseType.ScalarType, BaseType.ShortType, BaseType.StringType, BaseType.UnknownType, BaseType.UnsignedByteType, BaseType.UnsizedFixType, BaseType.XmlTokenType

public abstract class BaseType
extends java.lang.Object
implements Type

The type of base token classes. This class provides a type safe enumeration of base types.

Since:

Ptolemy II 0.4

Version:

$Id$

Author:

Yuhong Xiong, Steve Neuendorffer

Pt.AcceptedRating:

Red

Pt.ProposedRating:

Red (yuhong)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BaseType.ArrayBottomType	The bottom element of the array type lattice.
static class	BaseType.BooleanType	The boolean data type.
static class	BaseType.ComplexType	The complex data type.
static class	BaseType.DateType	The date data type.
static class	BaseType.DoubleType	The double data type.
static class	BaseType.EventType	The event data type.
static class	BaseType.FloatType	The float data type.
static class	BaseType.GeneralType	The general data type: The top of the lattice.
static class	BaseType.IntType	The integer data type.
static class	BaseType.LongType	The long integer data type.
static class	BaseType.NilType	The nil data type.
static class	BaseType.PetiteType	The petite data type.
static class	BaseType.ScalarType	The scalar data type: The least upper bound of all the scalar types.
static class	BaseType.ShortType	The short integer data type.
static class	BaseType.StringType	The string data type.
static class	BaseType.UnknownType	The bottom element of the data type lattice.
static class	BaseType.UnsignedByteType	The unsigned byte data type.
static class	BaseType.UnsizedFixType	The fix data type.
static class	BaseType.XmlTokenType	The XmlToken data type.

Field Summary

Fields

Modifier and Type	Field	Description
static Type	ACTOR	The actor data type.
static BaseType.ArrayBottomType	ARRAY_BOTTOM	The bottom element of the array type lattice.
static BaseType.BooleanType	BOOLEAN	The boolean data type.
static MatrixType.BooleanMatrixType	BOOLEAN_MATRIX	The boolean matrix data type.
static BaseType.ComplexType	COMPLEX	The complex data type.
static MatrixType.ComplexMatrixType	COMPLEX_MATRIX	The complex matrix data type.
static BaseType.DateType	DATE	The DateToken data type.
static BaseType.DoubleType	DOUBLE	The double data type.
static MatrixType.DoubleMatrixType	DOUBLE_MATRIX	The double matrix data type.
static BaseType.EventType	EVENT	The event data type.
static BaseType.UnsizedFixType	FIX	An alias for the unsized fix data type, provided for backward compatibility with the previous versions of Ptolemy.
static MatrixType.FixMatrixType	FIX_MATRIX	The fix matrix data type.
static BaseType.FloatType	FLOAT	The float data type.
static BaseType.GeneralType	GENERAL	The general data type: The top of the lattice.
static BaseType.IntType	INT	The integer data type.
static MatrixType.IntMatrixType	INT_MATRIX	The integer matrix data type.
static BaseType.LongType	LONG	The long integer data type.
static MatrixType.LongMatrixType	LONG_MATRIX	The long integer matrix data type.
static MatrixType	MATRIX	The matrix data type: The least upper bound of all the matrix types.
static BaseType.NilType	NIL	The nil data type.
static ObjectType	OBJECT	The object data type.
static BaseType.PetiteType	PETITE	The petite data type.
static RecordType	RECORD	Setting the type of something to RECORD allows it to take on a value that is any record with any fields.
static BaseType.ScalarType	SCALAR	The scalar data type: The least upper bound of all the scalar types.
static BaseType.ShortType	SHORT	The short integer data type.
static FixType	SIZED_FIX	The fix data type, with a precision specified.
static BaseType.StringType	STRING	The string data type.
static BaseType.UnknownType	UNKNOWN	The bottom element of the data type lattice.
static BaseType.UnsignedByteType	UNSIGNED_BYTE	The unsigned byte data type.
static BaseType.UnsizedFixType	UNSIZED_FIX	The unsized fix data type.
static BaseType.XmlTokenType	XMLTOKEN	The XmlToken data type.

Fields inherited from interface ptolemy.data.type.Type

HASH_INVALID

Method Summary

Modifier and Type	Method	Description
Type	add(Type rightArgumentType)	Return a new type which represents the type that results from adding a token of this type and a token of the given argument type.
static void	addType(Type type, java.lang.String name, java.lang.Class theClass)	Specify that the given type, with the given name, is implemented by the specified token class.
java.lang.Object	clone()	Return this, that is, return the reference to this object.
abstract Token	convert(Token t)	Convert the specified token to a token having the type represented by this object.
Type	divide(Type rightArgumentType)	Return a new type which represents the type that results from dividing a token of this type and a token of the given argument type.
boolean	equals(java.lang.Object object)	Determine if the argument represents the same BaseType as this object.
static Type	forClassName(java.lang.String className)	Return an instance of Type of that corresponds to tokens of a class with the given name, or null if none exists.
static Type	forName(java.lang.String name)	Return an instance of this class with the specified name, or null if none exists.
java.lang.Class	getTokenClass()	Return the class for tokens that this basetype represents.
int	getTypeHash()	Return a perfect hash for this type.
int	hashCode()	Return a hash code value for this object.
boolean	isAbstract()	Return true if this type does not correspond to a single token class.
boolean	isCompatible(Type type)	Test if the argument type is compatible with this type.
boolean	isConstant()	Test if this Type is UNKNOWN.
boolean	isInstantiable()	Determine if this type corresponds to an instantiable token classes.
boolean	isSubstitutionInstance(Type type)	Return true if the argument is a substitution instance of this type.
Type	modulo(Type rightArgumentType)	Return a new type which represents the type that results from moduloing a token of this type and a token of the given argument type.
Type	multiply(Type rightArgumentType)	Return a new type which represents the type that results from multiplying a token of this type and a token of the given argument type.
Type	one()	Return the type of the multiplicative identity for elements of this type.
Type	subtract(Type rightArgumentType)	Return a new type which represents the type that results from subtracting a token of this type and a token of the given argument type.
java.lang.String	toString()	Return the string representation of this type.
Type	zero()	Return the type of the additive identity for elements of this type.

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN

public static final BaseType.UnknownType UNKNOWN

The bottom element of the data type lattice.

ARRAY_BOTTOM

public static final BaseType.ArrayBottomType ARRAY_BOTTOM

The bottom element of the array type lattice.

BOOLEAN

public static final BaseType.BooleanType BOOLEAN

The boolean data type.

BOOLEAN_MATRIX

public static final MatrixType.BooleanMatrixType BOOLEAN_MATRIX

The boolean matrix data type.

UNSIGNED_BYTE

public static final BaseType.UnsignedByteType UNSIGNED_BYTE

The unsigned byte data type.

COMPLEX

public static final BaseType.ComplexType COMPLEX

The complex data type.

COMPLEX_MATRIX

public static final MatrixType.ComplexMatrixType COMPLEX_MATRIX

The complex matrix data type.

FLOAT

public static final BaseType.FloatType FLOAT

The float data type.

DOUBLE

public static final BaseType.DoubleType DOUBLE

The double data type.

DOUBLE_MATRIX

public static final MatrixType.DoubleMatrixType DOUBLE_MATRIX

The double matrix data type.

FIX

public static final BaseType.UnsizedFixType FIX

An alias for the unsized fix data type, provided for backward compatibility with the previous versions of Ptolemy.

UNSIZED_FIX

public static final BaseType.UnsizedFixType UNSIZED_FIX

The unsized fix data type.

SIZED_FIX

public static final FixType SIZED_FIX

The fix data type, with a precision specified.

FIX_MATRIX

public static final MatrixType.FixMatrixType FIX_MATRIX

The fix matrix data type.

SHORT

public static final BaseType.ShortType SHORT

The short integer data type.

INT

public static final BaseType.IntType INT

The integer data type.

INT_MATRIX

public static final MatrixType.IntMatrixType INT_MATRIX

The integer matrix data type.

LONG

public static final BaseType.LongType LONG

The long integer data type.

LONG_MATRIX

public static final MatrixType.LongMatrixType LONG_MATRIX

The long integer matrix data type.

OBJECT

public static final ObjectType OBJECT

The object data type.

ACTOR

public static final Type ACTOR

The actor data type.

XMLTOKEN

public static final BaseType.XmlTokenType XMLTOKEN

The XmlToken data type.

SCALAR

public static final BaseType.ScalarType SCALAR

The scalar data type: The least upper bound of all the scalar types.

MATRIX

public static final MatrixType MATRIX

The matrix data type: The least upper bound of all the matrix types.

STRING

public static final BaseType.StringType STRING

The string data type.

GENERAL

public static final BaseType.GeneralType GENERAL

The general data type: The top of the lattice.

EVENT

public static final BaseType.EventType EVENT

The event data type.

PETITE

public static final BaseType.PetiteType PETITE

The petite data type.

NIL

public static final BaseType.NilType NIL

The nil data type.

DATE

public static final BaseType.DateType DATE

The DateToken data type.

RECORD

public static final RecordType RECORD

Setting the type of something to RECORD allows it to take on a value that is any record with any fields. This is because a lossless conversion any such record to an empty record just returns the original record. So to force something to have a record type without specifying what fields it should have, do

    something.setTypeEquals(BaseType.RECORD);
  

To allow the type to resolve to a specific record type (with particular fields), do instead

    something.setTypeAtMost(BaseType.RECORD);
  

This will work for example to require a parameter to have a record value, but to allow its type to resolve to the specific record specified.

Method Detail

add

public Type add(Type rightArgumentType)

Return a new type which represents the type that results from adding a token of this type and a token of the given argument type.

Specified by:

add in interface Type

Parameters:

rightArgumentType - The type to add to this type.

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

addType

public static void addType(Type type,
                           java.lang.String name,
                           java.lang.Class theClass)

Specify that the given type, with the given name, is implemented by the specified token class. Normally, an end user won't need this method, but there is a particular use that can sometimes come in handy. Occasionally it is useful for a token that subclasses a standard token to be used in place of that standard token. For example, you could create a subclass of DoubleToken called DoublePlusPlus that includes some extra fields. For that class to be acceptable to the expression language, for example as a return type from a function, then you must call this method to register that class. In this case, you call it with arguments BaseType.DOUBLE, "doublePlusPlus" (or whatever name you choose), and DoublePlusPlus.class.

Parameters:

type - The type.

name - The name of the type.

theClass - The implementation (token class) for the type.

clone

public java.lang.Object clone()

Return this, that is, return the reference to this object.

Specified by:

clone in interface Type

Overrides:

clone in class java.lang.Object

Returns:

A BaseType.

convert

public abstract Token convert(Token t)
                       throws IllegalActionException

Convert the specified token to a token having the type represented by this object.

Specified by:

convert in interface Type

Parameters:

t - A token.

Returns:

A token.

Throws:

IllegalActionException - If lossless conversion cannot be done.

divide

public Type divide(Type rightArgumentType)

Return a new type which represents the type that results from dividing a token of this type and a token of the given argument type.

Specified by:

divide in interface Type

Parameters:

rightArgumentType - The type to add to this type.

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

equals

public boolean equals(java.lang.Object object)

Determine if the argument represents the same BaseType as this object.

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 BaseType as this object; false otherwise.

forClassName

public static Type forClassName(java.lang.String className)

Return an instance of Type of that corresponds to tokens of a class with the given name, or null if none exists.

Parameters:

className - The name of the class.

Returns:

An instance of BaseType.

forName

public static Type forName(java.lang.String name)

Return an instance of this class with the specified name, or null if none exists. Note that this does not recognize all the types that have symbolic names. It is better to use ptolemy.data.expr.Constants.types() to map a name to a type.

Parameters:

name - The name of the type.

Returns:

An instance of BaseType.

getTokenClass

public java.lang.Class getTokenClass()

Return the class for tokens that this basetype represents.

Specified by:

getTokenClass in interface Type

Returns:

The class for tokens that this type represents.

getTypeHash

public int getTypeHash()

Return a perfect hash for this type. This number corresponds uniquely to a particular type, and is used to improve performance of certain operations in the TypeLattice class. All instances of a particular type (e.g. integer array) must return the same number. Types that return HASH_INVALID will not have results in TypeLattice cached. Note that it is safer to return HASH_INVALID, than to return a number that is not unique, or different number for the same type from different instances. This base class returns HASH_INVALID.

Specified by:

getTypeHash in interface Type

Returns:

A number greater than or equal to 0, or HASH_INVALID.

hashCode

public int hashCode()

Return a hash code value for this object.

Overrides:

hashCode in class java.lang.Object

modulo

public Type modulo(Type rightArgumentType)

Return a new type which represents the type that results from moduloing a token of this type and a token of the given argument type.

Specified by:

modulo in interface Type

Parameters:

rightArgumentType - The type to add to this type.

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

multiply

public Type multiply(Type rightArgumentType)

Return a new type which represents the type that results from multiplying a token of this type and a token of the given argument type.

Specified by:

multiply in interface Type

Parameters:

rightArgumentType - The type to add to this type.

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

isAbstract

public boolean isAbstract()

Return true if this type does not correspond to a single token class. This occurs if the type is not instantiable, or it represents either an abstract base class or an interface.

Specified by:

isAbstract in interface Type

Returns:

True if this type does not correspond to a single token class.

isCompatible

public boolean isCompatible(Type type)

Test if the argument type is compatible with this type. The method returns true if this type is UNKNOWN, since any type is a substitution instance of it. If this type is not UNKNOWN, this method returns true if the argument type is less than or equal to this type in the type lattice, and false otherwise.

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 Type is UNKNOWN.

Specified by:

isConstant in interface Type

Returns:

True if this Type is not UNKNOWN; false otherwise.

isInstantiable

public boolean isInstantiable()

Determine if this type corresponds to an instantiable token classes. A BaseType is instantiable if it does not correspond to an abstract token class, or an interface, or UNKNOWN.

Specified by:

isInstantiable in interface Type

Returns:

True if this type is instantiable.

isSubstitutionInstance

public boolean isSubstitutionInstance(Type type)

Return true if the argument is a substitution instance of this type.

Specified by:

isSubstitutionInstance in interface Type

Parameters:

type - A Type.

Returns:

True if this type is UNKNOWN; false otherwise.

one

public Type one()

Return the type of the multiplicative identity for elements of this type.

Specified by:

one in interface Type

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

subtract

public Type subtract(Type rightArgumentType)

Return a new type which represents the type that results from subtracting a token of this type and a token of the given argument type.

Specified by:

subtract in interface Type

Parameters:

rightArgumentType - The type to add to this type.

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.

toString

public java.lang.String toString()

Return the string representation of this type.

Specified by:

toString in interface Type

Overrides:

toString in class java.lang.Object

Returns:

A String.

zero

public Type zero()

Return the type of the additive identity for elements of this type.

Specified by:

zero in interface Type

Returns:

A new type, or BaseType.GENERAL, if the operation does not make sense for the given types.