用正则表达式验证Email代码段

以下是一段使用正则表达式验证Email的代码段：

StringBuffer regex = new StringBuffer();
		regex.append("(([\\da-zA-Z]+[-._+&'])*[\\da-zA-Z]+)");//user name re
		regex.append("@(");
		regex.append("([0-9a-zA-Z]([-0-9a-zA-Z]{0,65}[0-9a-zA-Z])?\\.)");//domain name re
		regex.append("+(arpa|aero|biz|com|coop|edu|gov|info|int|mil|museum|name|net|org|pro|travel|xxx|jobs|mobi|post|ac|ad|ae|af|ag|ai|al|am|an|ao|aq|ar|as|at|au|aw|az|ba|bb|bd|be|bf|bg|bh|bi|bj|bm|bn|bo|br|bs|bt|bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|cr|cu|cv|cx|cy|cz|de|dj|dk|dm|do|dz|ec|ee|eg|er|es|et|fi|fj|fk|fm|fo|fr|ga|gd|ge|gf|gg|gh|gi|gl|gm|gn|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie|il|im|in|io|ir|is|it|je|jm|jo|jp|ke|kg|kh|ki|km|kn|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly|ma|mc|md|mg|mh|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|mv|mw|mx|my|mz|na|nc|ne|nf|ng|ni|nl|no|np|nr|nu|nz|om|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|ps|pt|pw|py|qa|re|ro|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sk|sl|sm|sn|sr|st|su|sv|sy|sz|tc|td|tf|tg|th|tj|tk|tm|tn|to|tr|tt|tv|tw|tz|ua|ug|uk|us|uy|uz|va|vc|ve|vg|vi|vn|vu|wf|ws|ye|yt|yu|za|zm|zw)");
		regex.append("|(((\\d|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])\\.){3}(\\d|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])|(0[xX]0*[\\da-fA-F]?[\\da-fA-F]\\.){3}0[xX]0*[\\da-fA-F]?[\\da-fA-F]|(0+[0-3][0-7][0-7]\\.){3}0+[0-3][0-7][0-7]|(0|[1-9]\\d{0,8}|[1-3]\\d{9}|4[01]\\d{8}|42[0-8]\\d{7}|429[0-3]\\d{6}|4294[0-8]\\d{5}|42949[0-5]\\d{4}|429496[0-6]\\d{3}|4294967[01]\\d{2}|42949672[0-8]\\d|429496729[0-5])|0[xX]0*[\\da-fA-F]{1,8}|([\\da-fA-F]{1,4}\\:){7}[\\da-fA-F]{1,4}|([\\da-fA-F]{1,4}\\:){6}((\\d|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])\\.){3}(\\d|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])))");
		
		Pattern pattern;
		Perl5Matcher matcher = new Perl5Matcher();

		try {
			pattern = new Perl5Compiler().compile(regex.toString());
			if(!matcher.matches(mail, pattern)){
				return "Invalid email format for " + title;
			}
		} catch (MalformedPatternException e) {
		}
		
		int usernamepos = mail.indexOf("@");
		if(usernamepos > 64) {
			return "Invalid email format for " + title;
		}

验证url的正则表达式：
((https?|ftp|gopher|telnet|file|notes|ms-help):((//)|(\\\\))+[\w\d:#@%/;$()~_?\+-=\\\.&]*)
java中的写法：
(https?|ftp|gopher|telnet|file|notes|ms-help):((//)|(\\\\\\\\))+[\\w\\d:#@%/;$()~_?\\+-=\\\\\\.&]*