检测Emai地址是否正确

//用户名：un
//域名：ym
//后缀名：hz

String un = "(^[//w&&[^_]][//w[.-]]+[//w&&[^.]&&[^-]&&[^_]])@";
String ym = "([[0-9]|[a-z]|[A_Z]|[-]]{1,10})//.";
String hz = "([^.][//w|[.]&&[^_]]+)";
String strEmail = un + ym + hz;

Pattern p = Pattern.compile(strEmail);
Matcher m = p.matcher(str);