java - 使用通配符验证 IP 地址

Question

String ip = "1.1.&.&";
String WILDCARD_CHARACTER = "&";
String REGEX_IP_ADDRESS_STRING = "(?:(?:"
        + WILDCARD_CHARACTER
        + "|25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:"
        + WILDCARD_CHARACTER + "|25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)";
Pattern p = Pattern.compile(REGEX_IP_ADDRESS_STRING1);
Matcher m = p.matcher(ip);
System.out.println("Does it match? " + m.matches());

使用上面编码的 IP 验证可以完美地工作。但是我想对导致问题的通配符进行一些修改。

当前场景:

• 192.1.&.& ------> 正确
• 192.1.0.1 ------> 正确
• & ------> 假
• 192.1.& ------> 错误

预期:

• 192.1.&.& ------> 假
• 192.1.0.1 ------> 正确
• & ------> 正确
• 192.1.& ------> 正确

即我想在通配符后通配所有输入。

对正则表达式进行哪些修改可以帮助我实现这一目标？任何人都可以帮忙吗？

Answer 1

我建议如下(我在此正则表达式中使用了文字 &；当然您可以将其更改为您的 + WILDCARD_CHARACTER 构造):

Pattern regex = Pattern.compile(
    "^       # Anchor the match at the start of the string\n" +
    "(?:     # Match either...\n" +
    " &      # the wildcard character\n" +
    " |      # or a number between 0 and 255\n" +
    " (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\n" +
    " \\.    # followed by a dot, followed by...\n" +
    " (?:    # ...either...\n" +
    "  &     # the wildcard character\n" +
    "  |     # or a number etc. etc.\n" +
    "  (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\n" +
    "  \\.\n" +
    "  (?:\n" +
    "   &\n" +
    "   |\n" +
    "   (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\n" +
    "   \\.\n" +
    "   (?:\n" +
    "    &\n" +
    "    |\n" +
    "    (?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\n" +
    "   )\n" +
    "  )\n" +
    " )\n" +
    ")\n" +
    "$        # Anchor the match at the end of the string", 
    Pattern.COMMENTS);