1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 #ifndef ADC_TKP_HXX 25 #define ADC_TKP_HXX 26 27 // USED SERVICES 28 // BASE CLASSES 29 // COMPONENTS 30 class CharacterSource; 31 class TkpContext; 32 // PARAMETRS 33 34 35 36 /** This is the interface for parser classes, which get a sequence of tokens from 37 a text. 38 39 Start() starts to parse the text from the given i_rSource. 40 GetNextToken() returns a Token on the heap as long as there are 41 still characters in the text left. This can be checked by 42 HasMore(). 43 44 The algorithms for parsing tokens from the text are an issue of 45 the derived classes. 46 */ 47 #if 0 48 /** 49 Parsing can be interrupted for a different source by PushSource(). 50 The parsing before interruption is continued after PopSource(). 51 */ 52 #endif // 0 53 54 class TokenParser 55 { 56 public: 57 // LIFECYCLE 58 TokenParser(); ~TokenParser()59 virtual ~TokenParser() {} 60 61 // OPERATIONS 62 /** Start parsing a character source. Any previously parsed sources 63 are discarded. 64 */ 65 virtual void Start( 66 CharacterSource & 67 i_rSource ); 68 69 /** @short Gets the next identifiable token out of the 70 source code. 71 */ 72 void GetNextToken(); 73 74 /// @return true, if there are more tokens to parse. HasMore() const75 bool HasMore() const { return bHasMore; } 76 77 private: 78 void InitSource( 79 CharacterSource & 80 i_rSource ); 81 82 virtual void SetStartContext() = 0; 83 virtual void SetCurrentContext( 84 TkpContext & io_rContext ) = 0; 85 virtual TkpContext & 86 CurrentContext() = 0; 87 // DATA 88 CharacterSource * pChars; 89 bool bHasMore; 90 }; 91 92 93 #endif 94 95 96