/* * 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 hivemall.tools.array; import hivemall.utils.hadoop.HiveUtils; import java.util.ArrayList; import java.util.List; import java.util.Set; import java.util.TreeSet; import org.apache.hadoop.hive.ql.exec.Description; import org.apache.hadoop.hive.ql.exec.UDFArgumentException; import org.apache.hadoop.hive.ql.metadata.HiveException; import org.apache.hadoop.hive.ql.udf.UDFType; import org.apache.hadoop.hive.ql.udf.generic.GenericUDF; import org.apache.hadoop.hive.serde2.objectinspector.ListObjectInspector; import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector; import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorFactory; import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorUtils; import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorUtils.ObjectInspectorCopyOption; /** * Return a list of unique entries for a given set of lists. * * <pre> * {1, 2} ∪ {1, 2} = {1, 2}, * {1, 2} ∪ {2, 3} = {1, 2, 3}, * {1, 2, 3} ∪ {3, 4, 5} = {1, 2, 3, 4, 5} * </pre> */ @Description(name = "array_union", value = "_FUNC_(array1, array2, ...) - Returns the union of a set of arrays", extended = "SELECT array_union(array(1,2),array(1,2));\n" + "[1,2]\n\n" + "SELECT array_union(array(1,2),array(2,3),array(2,5));\n" + "[1,2,3,5]") @UDFType(deterministic = true, stateful = false) public final class ArrayUnionUDF extends GenericUDF { private ListObjectInspector[] _listOIs; @Override public ObjectInspector initialize(ObjectInspector[] argOIs) throws UDFArgumentException { if (argOIs.length < 2) { throw new UDFArgumentException("Expecting at least two arrays as arguments"); } ListObjectInspector[] listOIs = new ListObjectInspector[argOIs.length]; ListObjectInspector arg0OI = HiveUtils.asListOI(argOIs[0]); listOIs[0] = arg0OI; ObjectInspector arg0ElemOI = arg0OI.getListElementObjectInspector(); for (int i = 1; i < argOIs.length; ++i) { ListObjectInspector checkOI = HiveUtils.asListOI(argOIs[i]); if (!ObjectInspectorUtils.compareTypes(arg0ElemOI, checkOI.getListElementObjectInspector())) { throw new UDFArgumentException("Array types does not match: " + arg0OI.getTypeName() + " != " + checkOI.getTypeName()); } listOIs[i] = checkOI; } this._listOIs = listOIs; return ObjectInspectorFactory.getStandardListObjectInspector( ObjectInspectorUtils.getStandardObjectInspector(arg0ElemOI, ObjectInspectorCopyOption.WRITABLE)); } @Override public List<Object> evaluate(DeferredObject[] args) throws HiveException { final Set<Object> objectSet = new TreeSet<Object>(); // new HashSet<Object>(); for (int i = 0; i < args.length; ++i) { final Object undeferred = args[i].get(); if (undeferred == null) { continue; } final ListObjectInspector oi = _listOIs[i]; final ObjectInspector elemOI = oi.getListElementObjectInspector(); for (int j = 0, len = oi.getListLength(undeferred); j < len; ++j) { Object nonStd = oi.getListElement(undeferred, j); Object copyed = ObjectInspectorUtils.copyToStandardObject(nonStd, elemOI, ObjectInspectorCopyOption.WRITABLE); objectSet.add(copyed); } } return new ArrayList<>(objectSet); } @Override public String getDisplayString(String[] args) { return "array_union(" + args[0] + ", " + args[1] + " )"; } }