1 files changed, 79 insertions, 0 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/data/ListHolder.java b/BJC-Utils2/src/main/java/bjc/utils/data/ListHolder.java
new file mode 100644
index 0000000..8dc33d3
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/data/ListHolder.java
@@ -0,0 +1,79 @@
+package bjc.utils.data;
+
+import java.util.function.Function;
+import java.util.function.UnaryOperator;
+
+import bjc.utils.funcdata.FunctionalList;
+import bjc.utils.funcdata.IFunctionalList;
+
+/**
+ * A holder that represents a set of non-deterministic computations
+ * 
+ * @author ben
+ *
+ * @param <ContainedType>
+ *            The type of contained value
+ */
+public class ListHolder<ContainedType> implements IHolder<ContainedType> {
+	private IFunctionalList<ContainedType> heldValues;
+
+	private ListHolder(IFunctionalList<ContainedType> toHold) {
+		heldValues = toHold;
+	}
+
+	/**
+	 * Create a new list holder
+	 * 
+	 * @param values
+	 *            The possible values for the computation
+	 */
+	@SafeVarargs
+	public ListHolder(ContainedType... values) {
+		heldValues = new FunctionalList<>();
+
+		if (values != null) {
+			for (ContainedType containedValue : values) {
+				heldValues.add(containedValue);
+			}
+		}
+	}
+
+	@Override
+	public <BoundType> IHolder<BoundType> bind(
+			Function<ContainedType, IHolder<BoundType>> binder) {
+		IFunctionalList<IHolder<BoundType>> boundValues = heldValues
+				.map(binder);
+
+		return new BoundListHolder<>(boundValues);
+	}
+
+	@Override
+	public <MappedType> IHolder<MappedType> map(
+			Function<ContainedType, MappedType> mapper) {
+		IFunctionalList<MappedType> mappedValues = heldValues.map(mapper);
+
+		return new ListHolder<>(mappedValues);
+	}
+
+	@Override
+	public IHolder<ContainedType> transform(
+			UnaryOperator<ContainedType> transformer) {
+		heldValues = heldValues.map(transformer);
+
+		return this;
+	}
+
+	@Override
+	public <UnwrappedType> UnwrappedType unwrap(
+			Function<ContainedType, UnwrappedType> unwrapper) {
+		return unwrapper.apply(heldValues.randItem());
+	}
+
+	@Override
+	public <NewType> Function<ContainedType, IHolder<NewType>> lift(
+			Function<ContainedType, NewType> func) {
+		return (val) -> {
+			return new ListHolder<>(new FunctionalList<>(func.apply(val)));
+		};
+	}
+}