| /* |
| * 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.wayang.spark.compiler; |
| |
| import org.apache.spark.api.java.function.FlatMapFunction; |
| import org.apache.wayang.core.function.FunctionDescriptor; |
| import org.apache.wayang.core.util.Iterators; |
| import org.apache.wayang.spark.execution.SparkExecutionContext; |
| |
| import java.util.ArrayList; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.function.Function; |
| |
| /** |
| * Wraps a {@link Function} as a {@link FlatMapFunction}. |
| */ |
| public class ExtendedMapPartitionsFunctionAdapter<InputType, OutputType> |
| implements FlatMapFunction<Iterator<InputType>, OutputType> { |
| |
| private final FunctionDescriptor.ExtendedSerializableFunction<Iterable<InputType>, Iterable<OutputType>> impl; |
| |
| private final SparkExecutionContext executionContext; |
| |
| public ExtendedMapPartitionsFunctionAdapter( |
| FunctionDescriptor.ExtendedSerializableFunction<Iterable<InputType>, Iterable<OutputType>> extendedFunction, |
| SparkExecutionContext sparkExecutionContext) { |
| this.impl = extendedFunction; |
| this.executionContext = sparkExecutionContext; |
| } |
| |
| @Override |
| public Iterator<OutputType> call(Iterator<InputType> it) throws Exception { |
| this.impl.open(executionContext); |
| List<OutputType> out = new ArrayList<>(); |
| while (it.hasNext()) { |
| final Iterable<OutputType> mappedPartition = this.impl.apply(Iterators.wrapWithIterable(it)); |
| for (OutputType dataQuantum : mappedPartition) { |
| out.add(dataQuantum); |
| } |
| } |
| return out.iterator(); |
| } |
| } |