Constructor Detail

• SwitchTransformer

  public SwitchTransformer(Predicate[] predicates,
                   Transformer[] transformers,
                   Transformer defaultTransformer)

  Constructor that performs no validation. Use getInstance if you want that.

  Parameters:

  predicates - array of predicates, not cloned, no nulls

  transformers - matching array of transformers, not cloned, no nulls

  defaultTransformer - the transformer to use if no match, null means return null

Method Detail

• getInstance

  public static Transformer getInstance(Predicate[] predicates,
                        Transformer[] transformers,
                        Transformer defaultTransformer)

  Factory method that performs validation and copies the parameter arrays.

  Parameters:

  predicates - array of predicates, cloned, no nulls

  transformers - matching array of transformers, cloned, no nulls

  defaultTransformer - the transformer to use if no match, null means return null

  Returns:

  the chained transformer

  Throws:

  IllegalArgumentException - if array is null

  IllegalArgumentException - if any element in the array is null

• getInstance

  public static Transformer getInstance(Map predicatesAndTransformers)

  Create a new Transformer that calls one of the transformers depending on the predicates.

  The Map consists of Predicate keys and Transformer values. A transformer is called if its matching predicate returns true. Each predicate is evaluated until one returns true. If no predicates evaluate to true, the default transformer is called. The default transformer is set in the map with a null key. The ordering is that of the iterator() method on the entryset collection of the map.

  Parameters:

  predicatesAndTransformers - a map of predicates to transformers

  Returns:

  the switch transformer

  Throws:

  IllegalArgumentException - if the map is null

  IllegalArgumentException - if any transformer in the map is null

  ClassCastException - if the map elements are of the wrong type

• transform

  public Object transform(Object input)

  Transforms the input to result by calling the transformer whose matching predicate returns true.

  Specified by:

  transform in interface Transformer

  Parameters:

  input - the input object to transform

  Returns:

  the transformed result

• getPredicates

  public Predicate[] getPredicates()

  Gets the predicates, do not modify the array.

  Returns:

  the predicates

  Since:

  Commons Collections 3.1

• getTransformers

  public Transformer[] getTransformers()

  Gets the transformers, do not modify the array.

  Returns:

  the transformers

  Since:

  Commons Collections 3.1

• getDefaultTransformer

  public Transformer getDefaultTransformer()

  Gets the default transformer.

  Returns:

  the default transformer

  Since:

  Commons Collections 3.1