net.mograsim.plugin.core/src/net/mograsim/plugin/asm/editor/rules/AsmLabelRule.java

   1 package net.mograsim.plugin.asm.editor.rules;\r
   2 \r
   3 import org.eclipse.core.runtime.Assert;\r
   4 import org.eclipse.jface.text.rules.ICharacterScanner;\r
   5 import org.eclipse.jface.text.rules.IRule;\r
   6 import org.eclipse.jface.text.rules.IToken;\r
   7 import org.eclipse.jface.text.rules.Token;\r
   8 \r
   9 public class AsmLabelRule implements IRule\r
  10 {\r
  11 \r
  12         /** The token to be returned when this rule is successful */\r
  13         protected IToken fToken;\r
  14 \r
  15         /**\r
  16          * Creates a rule which will return the specified token when a numerical sequence is detected.\r
  17          *\r
  18          * @param token the token to be returned\r
  19          */\r
  20         public AsmLabelRule(IToken token)\r
  21         {\r
  22                 Assert.isNotNull(token);\r
  23                 fToken = token;\r
  24         }\r
  25 \r
  26         @Override\r
  27         public IToken evaluate(ICharacterScanner scanner)\r
  28         {\r
  29                 int c = scanner.read();\r
  30                 int i = 1;\r
  31                 if (Character.isJavaIdentifierStart(c))\r
  32                 {\r
  33                         do\r
  34                         {\r
  35                                 c = scanner.read();\r
  36                                 i++;\r
  37                         } while (Character.isJavaIdentifierPart(c));\r
  38                         if (c == ':')\r
  39                                 return fToken;\r
  40                         return abort(scanner, i);\r
  41                 }\r
  42                 scanner.unread();\r
  43                 return Token.UNDEFINED;\r
  44         }\r
  45 \r
  46         private static IToken abort(ICharacterScanner scanner, int i)\r
  47         {\r
  48                 for (int j = 0; j < i; j++)\r
  49                         scanner.unread();\r
  50                 return Token.UNDEFINED;\r
  51         }\r
  52 }