- Add mapping lambda util methods that ease the in- and output operations of a...

- Add mapping lambda util methods that ease the in- and output operations of a mapped stream (less writing).
- Add a lambda util method for flatmap operations.
refs 2779

org.fortiss.tooling.common/trunk/src/org/fortiss/tooling/common/util/LambdaUtils.java

@@ -153,7 +153,7 @@ public class LambdaUtils {
 
 	/**
 	 * Applies the mapping {@link Function} {@code mapper} to the given collection and returns the
-	 * result as a list.
+	 * result as a collection whose implementation is given by the {@link Supplier}.
 	 * 
 	 * @param inColl
 	 *            Collection of input elements.
@@ -163,8 +163,56 @@ public class LambdaUtils {
 	 *            Supplier for the output {@link Collection}, e.g. TreeSet::new.
 	 * @return Collection of mapping results.
 	 */
-	public static <S, T> Collection<S> map(Collection<T> inColl, Function<T, S> mapper,
+	public static <S, T> Collection<S> mapInOut(Collection<T> inColl, Function<T, S> mapper,
 			Supplier<? extends Collection<S>> sup) {
 		return inColl.parallelStream().map(mapper).collect(Collectors.toCollection(sup));
 	}
+
+	/**
+	 * Applies the mapping {@link Function} {@code mapper} to the given collection and returns the
+	 * result as a {@code Stream}.
+	 * 
+	 * @param inColl
+	 *            Collection of input elements.
+	 * @param mapper
+	 *            Mapping function.
+	 * @return Stream of the mapping result.
+	 */
+	public static <S, T> Stream<S> mapIn(Collection<T> inColl, Function<T, S> mapper) {
+		return inColl.parallelStream().map(mapper);
+	}
+
+	/**
+	 * Applies the mapping {@link Function} {@code mapper} to the given {@code stream} and returns
+	 * the result as a collection whose implementation is given by the {@link Supplier}.
+	 * 
+	 * @param stream
+	 *            Stream of input elements.
+	 * @param mapper
+	 *            Mapping function.
+	 * @param sup
+	 *            Supplier for the output {@link Collection}, e.g. TreeSet::new.
+	 * @return Collection of mapping results.
+	 */
+	public static <S, T> Collection<S> mapOut(Stream<T> stream, Function<T, S> mapper,
+			Supplier<? extends Collection<S>> sup) {
+		return stream.map(mapper).collect(Collectors.toCollection(sup));
+	}
+
+	/**
+	 * Applies the flat mapping {@link Function} {@code mapper} to the given collection and returns
+	 * the result as a collection whose implementation is given by the {@link Supplier}.
+	 * 
+	 * @param inColl
+	 *            Collection of input elements.
+	 * @param mapper
+	 *            Mapping function.
+	 * @param sup
+	 *            Supplier for the output {@link Collection}, e.g. TreeSet::new.
+	 * @return Collection of mapping results.
+	 */
+	public static <S, T, R extends Stream<S>, U extends Collection<S>> Collection<S> flatMapInOut(
+			Collection<T> inColl, Function<T, R> mapper, Supplier<U> sup) {
+		return inColl.parallelStream().flatMap(mapper).collect(Collectors.toCollection(sup));
+	}
 }