Added interface to JDK collector API

1 files changed, 41 insertions, 0 deletions

diff --git a/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java
new file mode 100644
index 0000000..a44059b
--- /dev/null
+++ b/BJC-Utils2/src/main/java/bjc/utils/funcutils/CollectorUtils.java
@@ -0,0 +1,41 @@
+package bjc.utils.funcutils;
+
+import java.util.stream.Collector;
+
+import bjc.utils.data.IHolder;
+import bjc.utils.data.IPair;
+
+/**
+ * Utilities for producing implementations of {@link Collector}
+ * 
+ * @author ben
+ *
+ */
+public class CollectorUtils {
+	/**
+	 * Create a collector that applies two collectors at once
+	 * 
+	 * @param <InitialType>
+	 *            The type of the collection to collect from
+	 * @param <AuxType1>
+	 *            The intermediate type of the first collector
+	 * @param <AuxType2>
+	 *            The intermediate type of the second collector
+	 * @param <FinalType1>
+	 *            The final type of the first collector
+	 * @param <FinalType2>
+	 *            The final type of the second collector
+	 * @param firstCollector
+	 *            The first collector to use
+	 * @param secondCollector
+	 *            The second collector to use
+	 * @return A collector that functions as mentioned above
+	 */
+	public static <InitialType, AuxType1, AuxType2, FinalType1, FinalType2>
+			Collector<InitialType, IHolder<IPair<AuxType1, AuxType2>>, IPair<FinalType1, FinalType2>>
+			compoundCollect(
+					Collector<InitialType, AuxType1, FinalType1> firstCollector,
+					Collector<InitialType, AuxType2, FinalType2> secondCollector) {
+		return new CompoundCollector<>(firstCollector, secondCollector);
+	}
+}