001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2009 SonarSource SA
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.colorizer;
021    
022    import java.util.List;
023    
024    public class ColorizationEngine {
025    
026      private List<Tokenizer> tokenizers;
027      private CharacterTransformer charTransformer;
028    
029      public ColorizationEngine(List<Tokenizer> tokenizers) {
030        this(tokenizers, new NoTransformer());
031      }
032    
033      public ColorizationEngine(List<Tokenizer> tokenizers, CharacterTransformer charTransformer) {
034        this.tokenizers = tokenizers;
035        this.charTransformer = charTransformer;
036      }
037    
038      public final String colorize(String code) {
039        return colorize(new CodeReader(code));
040      }
041    
042      public final String colorize(CodeReader code) {
043        StringBuilder colorizedCode = new StringBuilder();
044        appendBeginOfFile(colorizedCode);
045        nextChar:
046        while (code.peek() != -1) {
047          for (Tokenizer codeTokenizer : tokenizers) {
048            if (codeTokenizer.hasNextToken(code)) {
049              appendNextToken(code, codeTokenizer, colorizedCode);
050              continue nextChar;
051            }
052          }
053    
054          transformAndAppend((char) code.pop(), colorizedCode);
055        }
056        appendEndOfFile(colorizedCode);
057        code.close();
058        return colorizedCode.toString();
059      }
060    
061      private void appendBeginOfFile(StringBuilder colorizedCode) {
062        for (Tokenizer tokenizer : tokenizers) {
063          colorizedCode.append(tokenizer.getTagBeginOfFile());
064        }
065      }
066    
067      private void appendEndOfFile(StringBuilder colorizedCode) {
068        for (Tokenizer tokenizer : tokenizers) {
069          colorizedCode.append(tokenizer.getTagEndOfFile());
070        }
071      }
072    
073      private void appendNextToken(CodeReader code, Tokenizer codeTokenizer, StringBuilder colorizedCode) {
074        colorizedCode.append(codeTokenizer.getTagBefore());
075        transformAndAppend(codeTokenizer.nextToken(code), colorizedCode);
076        colorizedCode.append(codeTokenizer.getTagAfter());
077      }
078    
079      private void transformAndAppend(String code, StringBuilder output) {
080        char[] chars = code.toCharArray();
081        for (char character : chars) {
082          transformAndAppend(character, output);
083        }
084      }
085    
086      private void transformAndAppend(char character, StringBuilder output) {
087        if (charTransformer.canTransform((int) character)) {
088          output.append(charTransformer.transform((int) character));
089        } else {
090          output.append(character);
091        }
092      }
093    
094    
095      private static class NoTransformer extends CharacterTransformer {
096        @Override
097        boolean canTransform(int character) {
098          return false;
099        }
100    
101        @Override
102        String transform(int character) {
103          throw new IllegalStateException("This method should not be called.");
104        }
105      }
106    }