| /* |
| * 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.Arrays; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.regex.PatternSyntaxException; |
| |
| import org.apache.pig.EvalFunc; |
| import org.apache.pig.PigWarning; |
| import org.apache.pig.data.Tuple; |
| import org.apache.pig.data.TupleFactory; |
| import org.apache.pig.impl.logicalLayer.schema.Schema; |
| import org.apache.pig.FuncSpec; |
| import org.apache.pig.data.DataType; |
| import org.apache.pig.impl.logicalLayer.FrontendException; |
| |
| |
| /** |
| * Wrapper around Java's String.split<br> |
| * input tuple: first column is assumed to have a string to split;<br> |
| * the optional second column is assumed to have the delimiter or regex to split on;<br> |
| * if not provided, it's assumed to be '\s' (space)<br> |
| * the optional third column may provide a limit to the number of results.<br> |
| * If limit is not provided, 0 is assumed, as per Java's split(). |
| */ |
| |
| public class STRSPLIT extends EvalFunc<Tuple> { |
| |
| private final static TupleFactory tupleFactory = TupleFactory.getInstance(); |
| |
| /** |
| * Wrapper around Java's String.split |
| * @param input tuple; first column is assumed to have a string to split; |
| * the optional second column is assumed to have the delimiter or regex to split on;<br> |
| * if not provided, it's assumed to be '\s' (space) |
| * the optional third column may provide a limit to the number of results.<br> |
| * If limit is not provided, 0 is assumed, as per Java's split(). |
| * @exception java.io.IOException |
| */ |
| @Override |
| public Tuple exec(Tuple input) throws IOException { |
| if (input == null || input.size() < 1) |
| return null; |
| try { |
| String source = (String) input.get(0); |
| String delim = (input.size() > 1 ) ? (String) input.get(1) : "\\s"; |
| int length = (input.size() > 2) ? (Integer) input.get(2) : 0; |
| if (source == null || delim == null) { |
| return null; |
| } |
| String[] splits = source.split(delim, length); |
| return tupleFactory.newTuple(Arrays.asList(splits)); |
| } catch (ClassCastException e) { |
| warn("class cast exception at "+e.getStackTrace()[0], PigWarning.UDF_WARNING_1); |
| } catch (PatternSyntaxException e) { |
| warn(e.getMessage(), PigWarning.UDF_WARNING_1); |
| } |
| // this only happens if the try block did not complete normally |
| return null; |
| } |
| |
| /* |
| * The outputSchema of STRSPLIT cannot be set as DataType.chararry otherwise in some cases, |
| * it will cause error. For example, when stringsize() is called. |
| */ |
| @Override |
| public Schema outputSchema(Schema input) { |
| return new Schema(new Schema.FieldSchema(null, DataType.TUPLE)); |
| } |
| |
| /* (non-Javadoc) |
| * @see org.apache.pig.EvalFunc#getArgToFuncMapping() |
| */ |
| @Override |
| public List<FuncSpec> getArgToFuncMapping() throws FrontendException { |
| List<FuncSpec> funcList = new ArrayList<FuncSpec>(); |
| Schema s = new Schema(new Schema.FieldSchema(null, DataType.CHARARRAY)); |
| |
| Schema s1 = new Schema(); |
| s1.add(new Schema.FieldSchema(null, DataType.CHARARRAY)); |
| s1.add(new Schema.FieldSchema(null, DataType.CHARARRAY)); |
| |
| Schema s2 = new Schema(); |
| s2.add(new Schema.FieldSchema(null, DataType.CHARARRAY)); |
| s2.add(new Schema.FieldSchema(null, DataType.CHARARRAY)); |
| s2.add(new Schema.FieldSchema(null, DataType.INTEGER)); |
| |
| funcList.add(new FuncSpec(this.getClass().getName(), s)); |
| funcList.add(new FuncSpec(this.getClass().getName(), s1)); |
| funcList.add(new FuncSpec(this.getClass().getName(), s2)); |
| return funcList; |
| } |
| |
| @Override |
| public boolean allowCompileTimeCalculation() { |
| return true; |
| } |
| } |