Fixing compilation in tests

Author: Alexey Kudinkin

hudi-client/hudi-spark-client/src/main/scala/org/apache/hudi/util/JFunction.scala

@@ -20,7 +20,12 @@ package org.apache.hudi.util
 // TODO scala-doc
 object JFunction {
 
-  def apply[T, R](f: java.util.function.Function[T, R]): T => R =
+  def toScala[T, R](f: java.util.function.Function[T, R]): T => R =
     (t: T) => f.apply(t)
 
+  def toJava[T](f: T => Unit): java.util.function.Consumer[T] =
+    new java.util.function.Consumer[T] {
+      override def accept(t: T): Unit = f.apply(t)
+    }
+
 }

hudi-client/hudi-spark-client/src/test/java/org/apache/hudi/testutils/HoodieClientTestHarness.java

@@ -213,7 +213,7 @@ protected void initSparkContexts(String appName) {
     context = new HoodieSparkEngineContext(jsc);
 
     sparkSession = SparkSession.builder()
-        .withExtensions(JFunction.apply(sparkSessionExtensions -> {
+        .withExtensions(JFunction.toScala(sparkSessionExtensions -> {
           sparkSessionExtensionsInjector.ifPresent(injector -> injector.accept(sparkSessionExtensions));
           return null;
         }))

hudi-spark-datasource/hudi-spark/src/test/scala/org/apache/hudi/functional/TestCOWDataSource.scala

@@ -31,6 +31,7 @@ import org.apache.hudi.exception.{HoodieException, HoodieUpsertException}
 import org.apache.hudi.keygen._
 import org.apache.hudi.keygen.constant.KeyGeneratorOptions.Config
 import org.apache.hudi.testutils.HoodieClientTestBase
+import org.apache.hudi.util.JFunction
 import org.apache.hudi.{AvroConversionUtils, DataSourceReadOptions, DataSourceWriteOptions, HoodieDataSourceHelpers}
 import org.apache.spark.sql._
 import org.apache.spark.sql.functions.{col, concat, lit, udf}
@@ -88,7 +89,10 @@ class TestCOWDataSource extends HoodieClientTestBase {
   }
 
   override def getSparkSessionExtensionsInjector: util.Option[Consumer[SparkSessionExtensions]] =
-    toJavaOption(Some((receiver: SparkSessionExtensions) => new HoodieSparkSessionExtension().apply(receiver)))
+    toJavaOption(
+      Some(
+        JFunction.toJava((receiver: SparkSessionExtensions) => new HoodieSparkSessionExtension().apply(receiver)))
+    )
 
   @Test def testShortNameStorage() {
     // Insert Operation

hudi-spark-datasource/hudi-spark/src/test/scala/org/apache/hudi/functional/TestMORDataSource.scala

@@ -31,6 +31,7 @@ import org.apache.hudi.index.HoodieIndex.IndexType
 import org.apache.hudi.keygen.NonpartitionedKeyGenerator
 import org.apache.hudi.keygen.constant.KeyGeneratorOptions.Config
 import org.apache.hudi.testutils.{DataSourceTestUtils, HoodieClientTestBase}
+import org.apache.hudi.util.JFunction
 import org.apache.hudi.{DataSourceReadOptions, DataSourceWriteOptions, HoodieDataSourceHelpers, SparkDatasetMixin}
 import org.apache.log4j.LogManager
 import org.apache.spark.sql._
@@ -80,7 +81,10 @@ class TestMORDataSource extends HoodieClientTestBase with SparkDatasetMixin {
   }
 
   override def getSparkSessionExtensionsInjector: util.Option[Consumer[SparkSessionExtensions]] =
-    toJavaOption(Some((receiver: SparkSessionExtensions) => new HoodieSparkSessionExtension().apply(receiver)))
+    toJavaOption(
+      Some(
+        JFunction.toJava((receiver: SparkSessionExtensions) => new HoodieSparkSessionExtension().apply(receiver)))
+    )
 
   @Test def testCount() {
     // First Operation: