[SPARK-4557][STREAMING] Spark Streaming foreachRDD Java API method should accept a VoidFunction<...>

Currently streaming foreachRDD Java API uses a function prototype requiring a return value of null.  This PR deprecates the old method and uses VoidFunction to allow for more concise declaration.  Also added VoidFunction2 to Java API in order to use in Streaming methods.  Unit test is added for using foreachRDD with VoidFunction, and changes have been tested with Java 7 and Java 8 using lambdas.

Author: Bryan Cutler <bjcutler@us.ibm.com>

Closes #9488 from BryanCutler/foreachRDD-VoidFunction-SPARK-4557.

1 files changed, 27 insertions, 0 deletions

diff --git a/core/src/main/java/org/apache/spark/api/java/function/VoidFunction2.java b/core/src/main/java/org/apache/spark/api/java/function/VoidFunction2.java
new file mode 100644
index 0000000000..6c576ab678
--- /dev/null
+++ b/core/src/main/java/org/apache/spark/api/java/function/VoidFunction2.java
@@ -0,0 +1,27 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.spark.api.java.function;
+
+import java.io.Serializable;
+
+/**
+ * A two-argument function that takes arguments of type T1 and T2 with no return value.
+ */
+public interface VoidFunction2<T1, T2> extends Serializable {
+  public void call(T1 v1, T2 v2) throws Exception;
+}