Java tutorial
/* * Copyright 2011,2012 Metamarkets Group Inc. * * Licensed 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 com.metamx.common.parsers; import com.google.common.collect.Maps; import com.metamx.common.IAE; import java.util.List; import java.util.Map; /** */ public class ToLowerCaseParser implements Parser<String, Object> { private final Parser baseParser; public ToLowerCaseParser(Parser baseParser) { this.baseParser = baseParser; } @Override public Map parse(String input) { Map<String, Object> line = baseParser.parse(input); Map<String, Object> retVal = Maps.newLinkedHashMap(); for (Map.Entry<String, Object> entry : line.entrySet()) { String k = entry.getKey().toLowerCase(); if (retVal.containsKey(k)) { // Duplicate key, case-insensitively throw new ParseException("Unparseable row. Duplicate key found : [%s]", k); } retVal.put(k, entry.getValue()); } return retVal; } @Override public void setFieldNames(Iterable<String> fieldNames) { baseParser.setFieldNames(fieldNames); } @Override public List<String> getFieldNames() { return baseParser.getFieldNames(); } }