MvcProvider.java

   1 package org.argeo.api.cms;
   2
   3 import java.util.function.BiFunction;
   4
   5 /**
   6  * Stateless UI part creator. Takes a parent view (V) and a model context (M) in
   7  * order to create a view part (W) which can then be further configured. Such
   8  * object can be used as services and reference other part of the model which
   9  * are relevant for all created UI part.
  10  */
  11 @FunctionalInterface
  12 public interface MvcProvider<V, M, W> extends BiFunction<V, M, W> {
  13         W createUiPart(V parent, M context);
  14
  15         /**
  16          * Whether this parent view is supported.
  17          *
  18          * @return true by default.
  19          */
  20         default boolean isViewSupported(V parent) {
  21                 return true;
  22         }
  23
  24         /**
  25          * Whether this context is supported.
  26          *
  27          * @return true by default.
  28          */
  29         default boolean isModelSupported(M context) {
  30                 return true;
  31         }
  32
  33         default W apply(V parent, M context) {
  34                 if (!isViewSupported(parent))
  35                         throw new IllegalArgumentException("Parent view " + parent + "is not supported.");
  36                 if (!isModelSupported(context))
  37                         throw new IllegalArgumentException("Model context " + context + "is not supported.");
  38                 return createUiPart(parent, context);
  39         }
  40
  41         default W createUiPart(V parent) {
  42                 return createUiPart(parent, null);
  43         }
  44 }