Package org.apache.commons.collections

Interface Transformer

All Known Implementing Classes:
ChainedTransformer, CloneTransformer, ClosureTransformer, ConstantTransformer, ExceptionTransformer, FactoryTransformer, InstantiateTransformer, InvokerTransformer, MapTransformer, NOPTransformer, PredicateTransformer, StringValueTransformer, SwitchTransformer
public interface Transformer
Defines a functor interface implemented by classes that transform one object into another.

A Transformer converts the input object to the output object. The input object should be left unchanged. Transformers are typically used for type conversions, or extracting data from an object.

Standard implementations of common transformers are provided by TransformerUtils. These include method invokation, returning a constant, cloning and returning the string value.

Since:
Commons Collections 1.0
Version:
$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $
Author:
James Strachan, Stephen Colebourne

  • Method Summary

    Modifier and Type
    Method
    Description
    Object
    transform(Object input)
    Transforms the input object (leaving it unchanged) into some output object.

  • Method Details

    • transform

      Object transform(Object input)
      Transforms the input object (leaving it unchanged) into some output object.
      Parameters:
      input - the object to be transformed, should be left unchanged
      Returns:
      a transformed object
      Throws:
      ClassCastException - (runtime) if the input is the wrong class
      IllegalArgumentException - (runtime) if the input is invalid
      FunctorException - (runtime) if the transform cannot be completed