/******************************************************************************* * Copyright (c) 2015-2018 Skymind, Inc. * * This program and the accompanying materials are made available under the * terms of the Apache License, Version 2.0 which is available at * https://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. * * SPDX-License-Identifier: Apache-2.0 ******************************************************************************/ package org.datavec.local.transforms.join; import lombok.AllArgsConstructor; import org.datavec.api.writable.Writable; import org.nd4j.common.function.Function; import org.nd4j.common.primitives.Pair; import java.util.ArrayList; import java.util.Collections; import java.util.List; /** Created by huitseeker on 3/6/17. */ @AllArgsConstructor public class ExtractKeysFunction implements Function<List<Writable>, Pair<List<Writable>, List<Writable>>> { private int[] columnIndexes; @Override public Pair<List<Writable>, List<Writable>> apply(List<Writable> writables) { List<Writable> keyValues; if (columnIndexes.length == 1) { keyValues = Collections.singletonList(writables.get(columnIndexes[0])); } else { keyValues = new ArrayList<>(columnIndexes.length); for (int i : columnIndexes) { keyValues.add(writables.get(i)); } } return Pair.of(keyValues, writables); } }