org.codehaus.jackson.type
Class TypeReference<T>
java.lang.Object
org.codehaus.jackson.type.TypeReference<T>
- All Implemented Interfaces:
- Comparable<TypeReference<T>>
public abstract class TypeReference<T>
- extends Object
- implements Comparable<TypeReference<T>>
This class is used to pass full generics type information, and
avoid problems with type erasure (that basically removes most
usable type references from runtime Class objects).
It is based on ideas from
http://gafter.blogspot.com/2006/12/super-type-tokens.html,
Additional idea (from a suggestion made in comments of the article)
is to require bogus implementation of Comparable
(any such generic interface would do, as long as it forces a method
with generic type to be implemented).
to ensure that a Type argument is indeed given.
Usage is by sub-classing: here is one way to instantiate reference
to generic type List<Integer>
:
TypeReference ref = new TypeReference<List<Integer>>() { };
which can be passed to methods that accept TypeReference.
Method Summary |
int |
compareTo(TypeReference<T> o)
The only reason we define this method (and require implementation
of Comparable ) is to prevent constructing a
reference without type information. |
Type |
getType()
|
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
TypeReference
protected TypeReference()
getType
public Type getType()
compareTo
public int compareTo(TypeReference<T> o)
- The only reason we define this method (and require implementation
of
Comparable
) is to prevent constructing a
reference without type information.
- Specified by:
compareTo
in interface Comparable<TypeReference<T>>