| /* |
| * 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.pig.builtin; |
| |
| import java.io.IOException; |
| import java.util.List; |
| import java.util.ArrayList; |
| |
| import org.apache.pig.EvalFunc; |
| import org.apache.pig.FuncSpec; |
| import org.apache.pig.data.Tuple; |
| import org.apache.pig.impl.logicalLayer.schema.Schema; |
| import org.apache.pig.data.DataType; |
| import org.apache.pig.impl.logicalLayer.FrontendException; |
| |
| /** |
| * ROUND implements a binding to the Java function |
| * {@link java.lang.Math#round(double) Math.round(double)}. |
| * Given a single data atom it Returns the closest long to the argument. |
| * |
| */ |
| public class ROUND extends EvalFunc<Long>{ |
| /** |
| * java level API |
| * @param input expects a single numeric value |
| * @return output returns a single numeric value, |
| * the closest long to the argument |
| */ |
| @Override |
| public Long exec(Tuple input) throws IOException { |
| if (input == null || input.size() == 0 || input.get(0) == null) |
| return null; |
| |
| try{ |
| Double d = DataType.toDouble(input.get(0)); |
| return Math.round(d); |
| } catch (NumberFormatException nfe){ |
| System.err.println("Failed to process input; error - " + nfe.getMessage()); |
| return null; |
| } catch (Exception e){ |
| throw new IOException("Caught exception processing input row ", e); |
| } |
| } |
| |
| @Override |
| public Schema outputSchema(Schema input) { |
| return new Schema(new Schema.FieldSchema(getSchemaName(this.getClass().getName().toLowerCase(), input), DataType.LONG)); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.apache.pig.EvalFunc#getArgToFuncMapping() |
| */ |
| @Override |
| public List<FuncSpec> getArgToFuncMapping() throws FrontendException { |
| List<FuncSpec> funcList = new ArrayList<FuncSpec>(); |
| funcList.add(new FuncSpec(this.getClass().getName(), new Schema(new Schema.FieldSchema(null, DataType.BYTEARRAY)))); |
| funcList.add(new FuncSpec(DoubleRound.class.getName(), new Schema(new Schema.FieldSchema(null, DataType.DOUBLE)))); |
| funcList.add(new FuncSpec(FloatRound.class.getName(), new Schema(new Schema.FieldSchema(null, DataType.FLOAT)))); |
| return funcList; |
| } |
| |
| @Override |
| public boolean allowCompileTimeCalculation() { |
| return true; |
| } |
| } |