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.
  • Constructor Details

    • TypeReference

      protected TypeReference()
  • Method Details

    • 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<T>