src/main/java/wtf/metio/reguloj/RuleBuilder.java

   1 package wtf.metio.reguloj;
   2
   3 import java.util.function.Consumer;
   4 import java.util.function.Predicate;
   5
   6 /**
   7  * <p>
   8  * Fluent interface for building new {@link Rule rules}. It follows the builder-pattern described
   9  * by Joshua Bloch (see Effective Java, Item 2) and offers 3 methods:
  10  * </p>
  11  * <ul>
  12  * <li>{@link #called(String) called}: Use this method to name your new rule.</li>
  13  * <li>{@link #when(Predicate) when}: Use this method to specify the {@link Predicate} for your new rule.</li>
  14  * <li>{@link #then(Consumer) then}: Use this method to specify the {@link Consumer} for your new rule.</li>
  15  * </ul>
  16  * <h2>Examples</h2>
  17  * <ol>
  18  * <li>
  19  * <p>
  20  * Rule creation with name, predicate and consumer:
  21  * </p>
  22  * <pre>
  23  * String name = "...";
  24  * Predicate predicate = ...;
  25  * Consumer consumer = ...;
  26  * Rule rule = Rule.builder()
  27  *               .called(<em>name</em>)
  28  *               .when(<em>predicate</em>)
  29  *               .then(<em>consumer</em>)
  30  * </pre>
  31  * </li>
  32  * </ol>
  33  *
  34  * @param <CONTEXT> The context type.
  35  * @see Rule
  36  * @see Context
  37  * @see Predicate
  38  * @see Consumer
  39  */
  40 public interface RuleBuilder<CONTEXT extends Context<?>> {
  41
  42     /**
  43      * Sets the {@link Predicate} for the new rule.
  44      *
  45      * @param predicate The predicate to set.
  46      * @return The current rule builder.
  47      */
  48     RuleBuilder<CONTEXT> when(Predicate<CONTEXT> predicate);
  49
  50     /**
  51      * Sets the {@link Consumer} for the new rule.
  52      *
  53      * @param consumer The consumer to set.
  54      * @return The current rule builder.
  55      */
  56     Rule<CONTEXT> then(Consumer<CONTEXT> consumer);
  57
  58     /**
  59      * Sets the name of the new rule.
  60      *
  61      * @param name The name to set.
  62      * @return The current rule builder.
  63      */
  64     RuleBuilder<CONTEXT> called(String name);
  65
  66 }