/tags/release-0.0.0-rc0/hive/external/ql/src/java/org/apache/hadoop/hive/ql/udf/generic/GenericUDFSize.java
Java | 84 lines | 55 code | 7 blank | 22 comment | 15 complexity | 7a100b11bd47f0e125b0d6c0ebface10 MD5 | raw file
Possible License(s): Apache-2.0, BSD-3-Clause, JSON, CPL-1.0
- /**
- * 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.hadoop.hive.ql.udf.generic;
- 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.exec.UDFArgumentTypeException;
- import org.apache.hadoop.hive.ql.metadata.HiveException;
- import org.apache.hadoop.hive.serde.Constants;
- import org.apache.hadoop.hive.serde2.objectinspector.ListObjectInspector;
- import org.apache.hadoop.hive.serde2.objectinspector.MapObjectInspector;
- import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
- import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector.Category;
- import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
- import org.apache.hadoop.io.IntWritable;
- /**
- * GenericUDFSize.
- *
- */
- @Description(name = "size", value = "_FUNC_(a) - Returns the size of a")
- public class GenericUDFSize extends GenericUDF {
- private ObjectInspector returnOI;
- private final IntWritable result = new IntWritable(-1);
- @Override
- public ObjectInspector initialize(ObjectInspector[] arguments)
- throws UDFArgumentException {
- if (arguments.length != 1) {
- throw new UDFArgumentLengthException(
- "The function SIZE only accepts 1 argument.");
- }
- Category category = arguments[0].getCategory();
- String typeName = arguments[0].getTypeName();
- if (category != Category.MAP && category != Category.LIST
- && !typeName.equals(Constants.VOID_TYPE_NAME)) {
- throw new UDFArgumentTypeException(0, "\""
- + Category.MAP.toString().toLowerCase() + "\" or \""
- + Category.LIST.toString().toLowerCase()
- + "\" is expected at function SIZE, " + "but \""
- + arguments[0].getTypeName() + "\" is found");
- }
- returnOI = arguments[0];
- return PrimitiveObjectInspectorFactory.writableIntObjectInspector;
- }
- @Override
- public Object evaluate(DeferredObject[] arguments) throws HiveException {
- Object data = arguments[0].get();
- if (returnOI.getCategory() == Category.MAP) {
- result.set(((MapObjectInspector) returnOI).getMapSize(data));
- } else if (returnOI.getCategory() == Category.LIST) {
- result.set(((ListObjectInspector) returnOI).getListLength(data));
- } else if (returnOI.getTypeName().equals(Constants.VOID_TYPE_NAME)) {
- // null
- result.set(-1);
- }
- return result;
- }
- @Override
- public String getDisplayString(String[] children) {
- assert (children.length == 1);
- return "size(" + children[0] + ")";
- }
- }