home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

What this is

This file is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Other links

The source code

/*
 *  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('^');
    }
}

new blog posts

 

Copyright 1998-2016 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.