Tools/Java/Source/Cpptasks/net/sf/antcontrib/cpptasks/parser/WhitespaceOrCaseInsensitiveLetterState.java

   1 /*
   2  *
   3  * Copyright 2002-2004 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) or whitespace.
  22  *
  23  * @author Curt Arnold
  24  */
  25 public final class WhitespaceOrCaseInsensitiveLetterState
  26     extends
  27     AbstractParserState {
  28   /**
  29    * Next state if the character is found.
  30    */
  31   private final AbstractParserState nextState;
  32
  33   /**
  34    * Character to match (lower case).
  35    */
  36   private final char lowerLetter;
  37
  38   /**
  39    * Character to match (upper case).
  40    */
  41   private final char upperLetter;
  42
  43   /**
  44    * Constructor.
  45    *
  46    * @param parser
  47    *            parser
  48    * @param matchLetter
  49    *            letter to match
  50    * @param nextStateArg
  51    *            next state if a match on the letter
  52    */
  53   public WhitespaceOrCaseInsensitiveLetterState(final AbstractParser parser,
  54                                                 final char matchLetter,
  55                                                 final AbstractParserState
  56                                                 nextStateArg) {
  57     super(parser);
  58     this.lowerLetter = Character.toLowerCase(matchLetter);
  59     this.upperLetter = Character.toUpperCase(matchLetter);
  60     this.nextState = nextStateArg;
  61   }
  62
  63   /**
  64    * Consumes a character and returns the next state for the parser.
  65    *
  66    * @param ch
  67    *            next character
  68    * @return the configured nextState if ch is the expected character or the
  69    *         configure noMatchState otherwise.
  70    */
  71   public AbstractParserState consume(final char ch) {
  72     if (ch == lowerLetter || ch == upperLetter) {
  73       return nextState;
  74     }
  75     if (ch == ' ' || ch == '\t') {
  76       return this;
  77     }
  78     if (ch == '\n') {
  79       getParser().getNewLineState();
  80     }
  81     return null;
  82   }
  83 }