org.teatrove.tea.compiler
Class Type

java.lang.Object
  org.teatrove.tea.compiler.Type

All Implemented Interfaces:

Serializable

public class Type
extends Object
implements Serializable

Immutable representation of an expression's type.

Author:

Brian S O'Neill

See Also:

Expression, Serialized Form

Field Summary

static Type	BOOLEAN_TYPE Type for representing booleans, provided as a convenience
static Type	INT_TYPE Type for representing ints, provided as a convenience
static Type	LONG_TYPE Type for representing longs, provided as a convenience
static Type	NON_NULL_STRING_TYPE Type for representing non-null Strings, provided as a convenience
static Type	NULL_TYPE Type that is compatble with all other types
static Type	OBJECT_TYPE Type that represents all objects, provided as a convenience
static Type	STRING_TYPE Type for representing Strings, provided as a convenience
static Type	VOID_TYPE Type that represents void, provided as a convenience

Constructor Summary

Type(Class<?> type)

Type(Class<?> type, Type generic)

Type(Class<?> type, TypedElement te)

Type(Class<?> type, Type generic, TypedElement te)

Type(GenericType type)

Type(GenericType type, TypedElement te)

Method Summary

int	convertableFrom(Type other) Returns the conversion cost of assigning the given type to this type.
boolean	equals(Object another)
static Class<?>	findCommonBaseClass(Class<?> a, Class<?> b) Returns the most specific common superclass or interface that can be used to represent both of the specified classes.
Method[]	getArrayAccessMethods() If this Type supports array lookup, then return all of the methods that can be called to access the array.
Type	getArrayElementType() If this Type supports array lookup, then return the element type.
Type[]	getArrayIndexTypes() If this Type supports array lookup, then return the index type.
String	getClassName()
Type	getCompatibleType(Type other) Returns a type that is compatible with this type, and the one passed in.
String	getFullName()
Type	getGenericClass() Returns the JDK 5 generic type associated with this type.
GenericType	getGenericType()
Type	getIterationElementType() If this type supports iteration, then the element type is returned.
static Type	getIterationType(GenericType type) Get the iteration type of the generic type based on the generic type parameters.
Type	getKeyElementType()
static Type	getKeyType(GenericType type) Get the key type of the generic type based on the generic type parameters.
Class<?>	getNaturalClass() Returns the natural class for this type.
Class<?>	getObjectClass() Class returned never represents a primitive type.
String	getSimpleName()
protected static Type	getTypeArgument(GenericType type, int index) Get the associated type of the generic type based on the generic type parameters.
Type	getValueElementType()
static Type	getValueType(GenericType type) Get the value type of the generic type based on the generic type parameters.
int	hashCode()
boolean	hasPrimitivePeer() Returns true if this type is not primitive, but it has a primitive type peer.
boolean	isNonNull() Returns true if this type cannot reference null.
boolean	isNullable() Returns true if this type can reference null, or simply the opposite result of isNonNull.
boolean	isPrimitive() Returns true if this type is a primitive.
boolean	isReverseIterationSupported() Returns true if this type supports iteration in the reverse direction.
boolean	isVoid() Return true if this type is void.
static Type	preserveType(Type currentType, Type newType) Preserve the current type's generic information with the specified new type if they have the same class.
Type	setArrayElementType(Type elementType) Accessed by the TypeChecker, to override the default.
Type	toNonNull() Returns this type converted such that it cannot reference null.
Type	toNonPrimitive() Returns a new type from this one that represents a non-primitive type.
Type	toNullable() Returns this type converted such that it can reference null.
Type	toPrimitive() Returns a new type from this one that represents a primitive type.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

NULL_TYPE

public static final Type NULL_TYPE

Type that is compatble with all other types

VOID_TYPE

public static final Type VOID_TYPE

Type that represents void, provided as a convenience

OBJECT_TYPE

public static final Type OBJECT_TYPE

Type that represents all objects, provided as a convenience

INT_TYPE

public static final Type INT_TYPE

Type for representing ints, provided as a convenience

LONG_TYPE

public static final Type LONG_TYPE

Type for representing longs, provided as a convenience

BOOLEAN_TYPE

public static final Type BOOLEAN_TYPE

Type for representing booleans, provided as a convenience

STRING_TYPE

public static final Type STRING_TYPE

Type for representing Strings, provided as a convenience

NON_NULL_STRING_TYPE

public static final Type NON_NULL_STRING_TYPE

Type for representing non-null Strings, provided as a convenience

Constructor Detail

Type

public Type(Class<?> type)

Type

public Type(Class<?> type,
            Type generic)

Type

public Type(GenericType type)

Type

public Type(Class<?> type,
            TypedElement te)

Type

public Type(Class<?> type,
            Type generic,
            TypedElement te)

Type

public Type(GenericType type,
            TypedElement te)

Method Detail

getClassName

public String getClassName()

getObjectClass

public Class<?> getObjectClass()

Class returned never represents a primitive type.

getGenericType

public GenericType getGenericType()

getGenericClass

public Type getGenericClass()

Returns the JDK 5 generic type associated with this type.

getNaturalClass

public Class<?> getNaturalClass()

Returns the natural class for this type. If type is primitive, then its primitive peer is returned.

isVoid

public boolean isVoid()

Return true if this type is void.

isPrimitive

public boolean isPrimitive()

Returns true if this type is a primitive.

hasPrimitivePeer

public boolean hasPrimitivePeer()

Returns true if this type is not primitive, but it has a primitive type peer.

toPrimitive

public Type toPrimitive()

Returns a new type from this one that represents a primitive type. If this type cannot be represented by a primitive, then this is returned.

toNonPrimitive

public Type toNonPrimitive()

Returns a new type from this one that represents a non-primitive type. If this type actually is primitive, the returned type is marked as not being able to reference null. i.e. if this type is int, new Type(Integer.class).toNonNull() is returned.

isNonNull

public boolean isNonNull()

Returns true if this type cannot reference null. For primitive types, true is always returned.

isNullable

public boolean isNullable()

Returns true if this type can reference null, or simply the opposite result of isNonNull.

toNonNull

public Type toNonNull()

Returns this type converted such that it cannot reference null.

toNullable

public Type toNullable()

Returns this type converted such that it can reference null. The resulting type is never primitive.

getArrayElementType

public Type getArrayElementType()
                         throws IntrospectionException

If this Type supports array lookup, then return the element type. Otherwise, null is returned.

Throws:

IntrospectionException

getArrayIndexTypes

public Type[] getArrayIndexTypes()
                          throws IntrospectionException

If this Type supports array lookup, then return the index type. Because the index type may be overloaded, an array is returned. Null is returned if this Type doesn't support array lookup.

Throws:

IntrospectionException

getArrayAccessMethods

public Method[] getArrayAccessMethods()
                               throws IntrospectionException

If this Type supports array lookup, then return all of the methods that can be called to access the array. If there are no methods, then an empty array is returned. Null is returned only if this Type doesn't support array lookup.

Throws:

IntrospectionException

getIterationElementType

public Type getIterationElementType()
                             throws IntrospectionException

If this type supports iteration, then the element type is returned. Otherwise, null is returned.

Throws:

IntrospectionException

getKeyElementType

public Type getKeyElementType()
                       throws IntrospectionException

Throws:

IntrospectionException

getValueElementType

public Type getValueElementType()
                         throws IntrospectionException

Throws:

IntrospectionException

isReverseIterationSupported

public boolean isReverseIterationSupported()

Returns true if this type supports iteration in the reverse direction.

setArrayElementType

public Type setArrayElementType(Type elementType)
                         throws IntrospectionException

Accessed by the TypeChecker, to override the default.

Throws:

IntrospectionException

getSimpleName

public String getSimpleName()

getFullName

public String getFullName()

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object another)

Overrides:

equals in class Object

getCompatibleType

public Type getCompatibleType(Type other)

Returns a type that is compatible with this type, and the one passed in. The type returned is selected using a best-fit algorithm.

If the type passed in represents a primitive type, but this type is not, the type returned is an object (or a subclass of), but never a primitive type. Compatible primitive types are returned when both this and the parameter type were already primitive types.

Input types which are arrays are also supported by this method.

Returns null if the given type isn't compatible with this one.

getIterationType

public static Type getIterationType(GenericType type)

Get the iteration type of the generic type based on the generic type parameters. If the type is not generic or has no resolvable type params, then OBJECT_TYPE is returned.

Parameters:

type - The generic type

Returns:

The iteration element type

getKeyType

public static Type getKeyType(GenericType type)

Get the key type of the generic type based on the generic type parameters. The key type is usually based around a map or key/value pair class containing 2 or more type arguments. If the type is not generic or has no resolvable type params, then OBJECT_TYPE is returned.

Parameters:

type - The generic type

Returns:

The key element type

getValueType

public static Type getValueType(GenericType type)

Get the value type of the generic type based on the generic type parameters. The kevaluey type is usually based around a map or key/value pair class containing 2 or more type arguments. If the type is not generic or has no resolvable type params, then OBJECT_TYPE is returned.

Parameters:

type - The generic type

Returns:

The value element type

getTypeArgument

protected static Type getTypeArgument(GenericType type,
                                      int index)

Get the associated type of the generic type based on the generic type parameters. If the type is not generic or has no resolvable type params, then OBJECT_TYPE is returned.

Parameters:

type - The generic type

index - The index of the type argument

Returns:

The element type

preserveType

public static Type preserveType(Type currentType,
                                Type newType)

Preserve the current type's generic information with the specified new type if they have the same class.

findCommonBaseClass

public static Class<?> findCommonBaseClass(Class<?> a,
                                           Class<?> b)

Returns the most specific common superclass or interface that can be used to represent both of the specified classes. Null is only returned if either class refers to a primitive type and isn't the same as the other class.

convertableFrom

public int convertableFrom(Type other)

Returns the conversion cost of assigning the given type to this type. Conversions are allowed between arrays as well if they have the same dimensions. If no legal conversion exists, -1 is returned. The conversion costs are as follows:

1. any type is assignable by its own type
2. any superclass type is assignable by a subclass type
3. any object with a primitive peer can be converted to its primitive
4. any primitive can be converted to its object peer
5. any byte or short can be widened to an int
6. any byte, short or int can be widened to a long
7. any byte or short can be widened to a float
8. any primitive number can be widened to a double
9. any Number object can be converted to a primitive and widened
10. any primitive number can be converted to a Number object
11. any primitive number can be widened to a Number object
12. any Number object can be widened to another Number object
13. any primitive number can be narrowed to a double
14. any Number object can be narrowed to a double
15. any primitive number can be narrowed to a Double object
16. any Number object can be narrowed to a Double object
17. any primitive number can be narrowed to a long
18. any Number object can be narrowed to a long
19. any primitive number can be narrowed to a Long object
20. any Number object can be narrowed to a Long object
21. any primitive number can be narrowed to a float
22. any Number object can be narrowed to a float
23. any primitive number can be narrowed to a Float object
24. any Number object can be narrowed to a Float object
25. any primitive number can be narrowed to a int
26. any Number object can be narrowed to a int
27. any primitive number can be narrowed to a Integer object
28. any Number object can be narrowed to a Integer object
29. any primitive number can be narrowed to a short
30. any Number object can be narrowed to a short
31. any primitive number can be narrowed to a Short object
32. any Number object can be narrowed to a Short object
33. any primitive number can be narrowed to a byte
34. any Number object can be narrowed to a byte
35. any primitive number can be narrowed to a Byte object
36. any Number object can be narrowed to a Byte object
37. any primitive can be converted to an object
38. NULL_TYPE can be converted to any object
39. anything can be converted to a String

Returns:

the conversion cost, or -1 if the other can't assign to this