Encapsulate cloning behavior of in-process ParDo evaluator

sdks/java/core/src/main/java/org/apache/beam/sdk/runners/inprocess/CloningSupplier.java

@@ -0,0 +1,42 @@
+/*
+ * 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.beam.sdk.runners.inprocess;
+
+import org.apache.beam.sdk.util.SerializableUtils;
+
+import com.google.common.base.Supplier;
+
+import java.io.Serializable;
+
+class CloningSupplier<T extends Serializable> implements Supplier<T> {
+  private final T value;
+
+  public static <ValueT extends Serializable> CloningSupplier<ValueT> forValue(ValueT value) {
+    return new CloningSupplier<>(value);
+  }
+
+  private CloningSupplier(T value) {
+    this.value = value;
+  }
+
+  @Override
+  public T get() {
+    return SerializableUtils.clone(value);
+  }
+}

sdks/java/core/src/main/java/org/apache/beam/sdk/runners/inprocess/ParDoInProcessEvaluator.java

@@ -25,7 +25,6 @@
 import org.apache.beam.sdk.util.DoFnRunner;
 import org.apache.beam.sdk.util.DoFnRunners;
 import org.apache.beam.sdk.util.DoFnRunners.OutputManager;
-import org.apache.beam.sdk.util.SerializableUtils;
 import org.apache.beam.sdk.util.UserCodeException;
 import org.apache.beam.sdk.util.WindowedValue;
 import org.apache.beam.sdk.util.common.CounterSet;
@@ -34,6 +33,8 @@
 import org.apache.beam.sdk.values.PCollectionView;
 import org.apache.beam.sdk.values.TupleTag;
 
+import com.google.common.base.Supplier;
+
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -45,7 +46,7 @@ public static <InputT, OutputT> ParDoInProcessEvaluator<InputT> create(
       InProcessEvaluationContext evaluationContext,
       CommittedBundle<InputT> inputBundle,
       AppliedPTransform<PCollection<InputT>, ?, ?> application,
-      DoFn<InputT, OutputT> fn,
+      Supplier<DoFn<InputT, OutputT>> fnSupplier,
       List<PCollectionView<?>> sideInputs,
       TupleTag<OutputT> mainOutputTag,
       List<TupleTag<?>> sideOutputTags,
@@ -68,7 +69,7 @@ public static <InputT, OutputT> ParDoInProcessEvaluator<InputT> create(
     DoFnRunner<InputT, OutputT> runner =
         DoFnRunners.createDefault(
             evaluationContext.getPipelineOptions(),
-            SerializableUtils.clone(fn),
+            fnSupplier.get(),
             evaluationContext.createSideInputReader(sideInputs),
             BundleOutputManager.create(outputBundles),
             mainOutputTag,

sdks/java/core/src/main/java/org/apache/beam/sdk/runners/inprocess/ParDoMultiEvaluatorFactory.java

@@ -54,7 +54,7 @@ private static <InT, OuT> ParDoInProcessEvaluator<InT> createMultiEvaluator(
         evaluationContext,
         inputBundle,
         application,
-        fn,
+        CloningSupplier.forValue(fn),
         application.getTransform().getSideInputs(),
         application.getTransform().getMainOutputTag(),
         application.getTransform().getSideOutputTags().getAll(),

sdks/java/core/src/main/java/org/apache/beam/sdk/runners/inprocess/ParDoSingleEvaluatorFactory.java

@@ -33,6 +33,8 @@
  * {@link Bound ParDo.Bound} primitive {@link PTransform}.
  */
 class ParDoSingleEvaluatorFactory implements TransformEvaluatorFactory {
+
+
   @Override
   public <T> TransformEvaluator<T> forApplication(
       final AppliedPTransform<?, ?, ?> application,
@@ -45,16 +47,18 @@ public <T> TransformEvaluator<T> forApplication(
   }
 
   private static <InputT, OutputT> ParDoInProcessEvaluator<InputT> createSingleEvaluator(
-      @SuppressWarnings("rawtypes") AppliedPTransform<PCollection<InputT>, PCollection<OutputT>,
-          Bound<InputT, OutputT>> application,
-      CommittedBundle<InputT> inputBundle, InProcessEvaluationContext evaluationContext) {
+      @SuppressWarnings("rawtypes")
+      final AppliedPTransform<PCollection<InputT>, PCollection<OutputT>, Bound<InputT, OutputT>>
+          application,
+      CommittedBundle<InputT> inputBundle,
+      InProcessEvaluationContext evaluationContext) {
     TupleTag<OutputT> mainOutputTag = new TupleTag<>("out");
 
     return ParDoInProcessEvaluator.create(
         evaluationContext,
         inputBundle,
         application,
-        application.getTransform().getFn(),
+        CloningSupplier.forValue(application.getTransform().getFn()),
         application.getTransform().getSideInputs(),
         mainOutputTag,
         Collections.<TupleTag<?>>emptyList(),