bayou.jtype

Class ClassType<T>

java.lang.Object

bayou.jtype.JavaType<T>

bayou.jtype.ReferenceType<T>

bayou.jtype.ClassType<T>

All Implemented Interfaces:

TypeArg

public abstract class ClassType<T>
extends ReferenceType<T>

Class or interface type. ( Ideally this should be named as ClassOrInterfaceType, but that would be too long. )

A ClassType may represent a parameterized types, e.g. Map<String,Integer>.

A ClassType can be created by one of the static factory methods, for example

     ClassType< Map<String,Integer> > type = ClassType.of(Map.class, String.class, Integer.class);
 

or as "type literal" by anonymous subclass , for example

     new ClassType< List<String> > (){}
 

Field Summary

Fields

Modifier and Type	Field and Description
static ClassType<Object>	OBJECT The java.lang.Object type.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ClassType() For anonymous subclass to create type literal.

Method Summary

Instance Methods
Class<T>	getTheClass() Get the class or interface of this type.
List<TypeArg>	getTypeArgs() Get the type arguments.
List<TypeVar<?>>	getTypeVars() Get the type variables of the class/interface definition.
boolean	isRawType() Whether this is a raw type.
boolean	hasWildcard() Whether any type argument is a wildcard.
int	hashCode()
boolean	equals(Object obj) Whether this type is equal to another type.
String	toString(boolean full) A textual description of the type.
Static Methods
<C,T extends C> ClassType<T>	of(Class<C> clazz, TypeArg... typeArgs) Create a ClassType with the class and type arguments.
<C,T extends C> ClassType<T>	of(Class<C> clazz, Class<?>... typeArgs) Create a ClassType with the class and type arguments.
<T> ClassType<T>	of(Class<T> clazz) Create a ClassType representing the class.
<C> ClassType<? extends C>	withTypeVars(Class<C> clazz) Create a ClassType, using type variables as type arguments.

Methods inherited from class bayou.jtype.JavaType

convertFrom, toString

Methods inherited from class java.lang.Object

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

Field Detail

OBJECT

public static final ClassType<Object> OBJECT

The java.lang.Object type.

Constructor Detail

ClassType

protected ClassType()

For anonymous subclass to create type literal.

This protected constructor is only intended to be used to create "type literal" by anonymous subclass. For example

     new ClassType< List<String> > (){}
 

Method Detail

of

public static <C,T extends C> ClassType<T> of(Class<C> clazz,
                                              TypeArg... typeArgs)

Create a ClassType with the class and type arguments.

If `clazz` is generic, and `typeArgs` is empty, this method creates a raw type.

of

public static <C,T extends C> ClassType<T> of(Class<C> clazz,
                                              Class<?>... typeArgs)

Create a ClassType with the class and type arguments.

This is a convenience method for of(Class, TypeArg...) by converting each Class to a TypeArg.

Example

     ClassType<Map<String,Integer>> type = ClassType.of(Map.class, String.class, Integer.class);
 

of

public static <T> ClassType<T> of(Class<T> clazz)

Create a ClassType representing the class. For example

     ClassType<String> type = ClassType.of(String.class);
 

If `clazz` is generic, this method creates a raw type.

withTypeVars

public static <C> ClassType<? extends C> withTypeVars(Class<C> clazz)

Create a ClassType, using type variables as type arguments.

For example, ClassType.withTypeVars(java.util.Map.class) returns a ClassType<K,V> where K,V are type variables defined on java.util.Map<K,V>.

getTheClass

public final Class<T> getTheClass()

Get the class or interface of this type.

For example, if this ClassType represents List<String>, this method will return List.class.

Strictly speaking, the return type of this method should be Class<|T|> where |T| is the erasure of T. However, we cannot express that constraint precisely. Therefore the return type might be for example Class<List<String>> which technically does not exist.

getTypeArgs

public final List<TypeArg> getTypeArgs()

Get the type arguments.

For example, if this ClassType represents Map<String,Integer>, this method returns [String,Integer].

Return an empty list if this is not a parameterized type, either because the class/interface is non-generic, or this is a raw type.

getTypeVars

public final List<TypeVar<?>> getTypeVars()

Get the type variables of the class/interface definition.

For example, if getTheClass() is java.util.Map.class, this method returns [K,V] as they are declared on Map.

Return an empty list if the class/interface is not generic.

isRawType

public final boolean isRawType()

Whether this is a raw type.

If the class/interface is generic, but there is no type arguments for this ClassType, this is a raw type.

hasWildcard

public final boolean hasWildcard()

Whether any type argument is a wildcard.

hashCode

public final int hashCode()

Overrides:

hashCode in class JavaType<T>

equals

public final boolean equals(Object obj)

Whether this type is equal to another type.

A `ClassType` is only equal to another `ClassType` with the same class and the same type arguments.

Overrides:

equals in class JavaType<T>

toString

public final String toString(boolean full)

Description copied from class: JavaType

A textual description of the type.

If `full==false`, simpler names are used for types.

For example:

    ClassType< List<String> > type = ClassType.of(List.class, String.class);

    type.toString(true);    //  "java.util.List<java.lang.String>"
    type.toString(false);   //  "List<String>"
 

Specified by:

toString in interface TypeArg

Specified by:

toString in class JavaType<T>