/* * 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 javax.annotation.Nullable; import org.apache.commons.lang3.StringUtils; import org.apache.hadoop.hive.ql.exec.Description; import org.apache.hadoop.hive.ql.exec.UDFArgumentException; import org.apache.hadoop.hive.ql.exec.UDFArgumentLengthException; 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.primitive.PrimitiveObjectInspectorFactory; import org.apache.hadoop.hive.serde2.objectinspector.primitive.StringObjectInspector; @Description(name = "array_to_str", value = "_FUNC_(array arr [, string sep=',']) - Convert array to string using a sperator", extended = "SELECT array_to_str(array(1,2,3),'-');\n" + "1-2-3") @UDFType(deterministic = true, stateful = false) public final class ArrayToStrUDF extends GenericUDF { private ListObjectInspector listOI; @Nullable private StringObjectInspector sepOI; @Override public ObjectInspector initialize(ObjectInspector[] argOIs) throws UDFArgumentException { if (argOIs.length != 1 && argOIs.length != 2) { throw new UDFArgumentLengthException( "array_to_str(array, string sep) expects one or two arguments: " + argOIs.length); } this.listOI = HiveUtils.asListOI(argOIs[0]); if (argOIs.length == 2) { this.sepOI = HiveUtils.asStringOI(argOIs[1]); } return PrimitiveObjectInspectorFactory.javaStringObjectInspector; } @Override public String evaluate(DeferredObject[] arguments) throws HiveException { Object arg0 = arguments[0].get(); if (arg0 == null) { return null; } String sep = ","; if (arguments.length == 2) { Object arg1 = arguments[1].get(); if (arg1 != null) { sep = sepOI.getPrimitiveJavaObject(arg1); } } final StringBuilder buf = new StringBuilder(); final int len = listOI.getListLength(arg0); for (int i = 0; i < len; i++) { Object e = listOI.getListElement(arg0, i); if (e != null) { if (i != 0 && buf.length() > 0) { buf.append(sep); } buf.append(e.toString()); } } return buf.toString(); } @Override public String getDisplayString(String[] children) { return "array_to_str(" + StringUtils.join(children, ',') + ")"; } }