Tools/Source/Cpptasks/net/sf/antcontrib/cpptasks/parser/CaseInsensitiveLetterState.java

   1 /*
   2  *
   3  * Copyright 2004 The Ant-Contrib project
   4  *
   5  *  Licensed under the Apache License, Version 2.0 (the "License");
   6  *  you may not use this file except in compliance with the License.
   7  *  You may obtain a copy of the License at
   8  *
   9  *      http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  *  Unless required by applicable law or agreed to in writing, software
  12  *  distributed under the License is distributed on an "AS IS" BASIS,
  13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  *  See the License for the specific language governing permissions and
  15  *  limitations under the License.
  16  */
  17 package net.sf.antcontrib.cpptasks.parser;
  18
  19 /**
  20  * This parser state checks consumed characters against a specific character
  21  * (case insensitive).
  22  *
  23  * @author Curt Arnold
  24  */
  25 public final class CaseInsensitiveLetterState
  26     extends AbstractParserState {
  27   /**
  28    * Next state if a match is found.
  29    */
  30   private final AbstractParserState nextState;
  31
  32   /**
  33    * Next state if not match is found.
  34    */
  35   private final AbstractParserState noMatchState;
  36
  37   /**
  38    * Lower case version of character to match.
  39    */
  40   private final char lowerLetter;
  41
  42   /**
  43    * Lower case version of character to match.
  44    */
  45   private final char upperLetter;
  46
  47   /**
  48    * Constructor.
  49    *
  50    * @param parser
  51    *            parser
  52    * @param matchLetter
  53    *            letter to match
  54    * @param nextStateArg
  55    *            next state if a match on the letter
  56    * @param noMatchStateArg
  57    *            state if no match on letter
  58    */
  59   public CaseInsensitiveLetterState(final AbstractParser parser,
  60                                     final char matchLetter,
  61                                     final AbstractParserState nextStateArg,
  62                                     final AbstractParserState noMatchStateArg) {
  63     super(parser);
  64     this.lowerLetter = Character.toLowerCase(matchLetter);
  65     this.upperLetter = Character.toUpperCase(matchLetter);
  66     this.nextState = nextStateArg;
  67     this.noMatchState = noMatchStateArg;
  68   }
  69
  70   /**
  71    * Consumes a character and returns the next state for the parser.
  72    *
  73    * @param ch
  74    *            next character
  75    * @return the configured nextState if ch is the expected character or the
  76    *         configure noMatchState otherwise.
  77    */
  78   public AbstractParserState consume(final char ch) {
  79     if (ch == lowerLetter || ch == upperLetter) {
  80       return nextState;
  81     }
  82     if (ch == '\n') {
  83       getParser().getNewLineState();
  84     }
  85     return noMatchState;
  86   }
  87 }