2003/06/28 06:54:18

[org.ibex.core.git] / src / gnu / regexp / RETokenStart.java

diff --git a/src/gnu/regexp/RETokenStart.java b/src/gnu/regexp/RETokenStart.java
new file mode 100644 (file)
index 0000000..f411572
--- /dev/null
+++ b/src/gnu/regexp/RETokenStart.java
@@ -0,0 +1,69 @@
+/*
+ *  gnu/regexp/RETokenStart.java
+ *  Copyright (C) 1998-2001 Wes Biggs
+ *
+ *  This library is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License as published
+ *  by the Free Software Foundation; either version 2.1 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+package gnu.regexp;
+
+class RETokenStart extends REToken {
+    private String newline; // matches after a newline
+    
+    RETokenStart(int subIndex, String newline) {
+       super(subIndex);
+       this.newline = newline;
+    }
+    
+    boolean match(CharIndexed input, REMatch mymatch) {
+       // charAt(index-n) may be unknown on a Reader/InputStream. FIXME
+       // Match after a newline if in multiline mode
+       
+       if (newline != null) {
+           int len = newline.length();
+           if (mymatch.offset >= len) {
+               boolean found = true;
+               char z;
+               int i = 0; // position in REToken.newline
+               char ch = input.charAt(mymatch.index - len);
+               do {
+                   z = newline.charAt(i);
+                   if (ch != z) {
+                       found = false;
+                       break;
+                   }
+                   ++i;
+                   ch = input.charAt(mymatch.index - len + i);
+               } while (i < len);
+           
+               if (found) return next(input, mymatch);
+           }
+       }
+       
+       // Don't match at all if REG_NOTBOL is set.
+       if ((mymatch.eflags & RE.REG_NOTBOL) > 0) return false;
+       
+       if ((mymatch.eflags & RE.REG_ANCHORINDEX) > 0)
+           return (mymatch.anchor == mymatch.offset) ? 
+               next(input, mymatch) : false;
+       else
+           return ((mymatch.index == 0) && (mymatch.offset == 0)) ?
+               next(input, mymatch) : false;
+    }
+    
+    void dump(StringBuffer os) {
+       os.append('^');
+    }
+}