public class RegMatcher {

	private static Hashtable cache = new Hashtable(); //patterns cache


	/**
     * We use null for 'All' - not to make matching with ".*" - when no need
     */
    public static boolean matches(String string, String pattern) throws Exception{

    	if(pattern==null) //we use null to match with everything for efficiency
        	return true;  //('All' - the most frequent value been transformed to null)

        Pattern p = (Pattern)cache.get(pattern);
        if(p==null){
        	p = Pattern.compile(pattern);
        	cache.put(pattern, p);
        }

        return p.matcher(string.trim()).matches();
    }


}

Usage example:

        //email validation pattern which works
	public final static String EMAIL_VALIDATION_PATTERN = "^[_A-Za-z0-9-+']+(\\.[_A-Za-z0-9-+']+)*@[A-Za-z0-9-]+(\\.[A-Za-z0-9-]+)*(\\.[A-Za-z]{2,})$";
	public final static String CONTACT_NAME_VALIDATION_PATTERN_NOT = ".*[~`!@#$^*_+=|\\<>?/].*";
	...

public void testMatchesEmail() throws Exception{
	assertTrue(RegMatcher.matches("a@b.COM", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("a@b", Constants.EMAIL_VALIDATION_PATTERN));
	assertTrue(RegMatcher.matches("a@b.c.d.AAZ", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("ab.c", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("a@BBB@c", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("@b.c", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("AAAa@", Constants.EMAIL_VALIDATION_PATTERN));
	assertTrue(RegMatcher.matches("_@a.bb", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("scassel@org", Constants.EMAIL_VALIDATION_PATTERN));
	assertTrue(RegMatcher.matches("some_real@ontario.aaaaaaaaaaaaaaaaaaaaaaaaaaa", Constants.EMAIL_VALIDATION_PATTERN));
	assertFalse(RegMatcher.matches("O'Henry@org", Constants.EMAIL_VALIDATION_PATTERN));
}