我可以在以下条件下为java中的以下字符串获取适当的正则表达式吗

Karthikeyan V 发表于 Dev

卡尔提克扬五世

测试字符串是

It is a test data
%Warning: portfast should only be enabled on ports connected to a single
 host. Connecting hubs, concentrators, switches, bridges, etc. to this
 interface when portfast is enabled can cause temporary bridging loops.
 Use with CAUTION
Test is a test.

如果字符串中包含%符号，则该字符串无效。但是，如果在%后面加上以下字符序列，则是有效的，即“％Warning：portfast仅应在连接到单个主机的端口上启用。将集线器，集中器，交换机，网桥等连接到此\ n接口启用portfast时可能会导致临时桥接循环。\ n小心使用“。即使在这种情况下，'％'符号也只能出现一次。

我的代码是：

public class Abc {

    public static void main(String[] args) {
        String reg="%(Warning: portfast should only be enabled on ports connected to a single\n host. Connecting hubs, concentrators, switches, bridges, etc. to this\n interface when portfast is enabled can cause temporary bridging loops.\n Use with CAUTION)([^%])";
        String str = "%Warning: portfast should only be enabled on ports connected to a single\n host. Connecting hubs, concentrators, switches, bridges, etc. to this\n interface when portfast is enabled can cause temporary bridging loops.\n Use with CAUTIONTest is a testData is invalid%";
        Pattern regEx2 = Pattern
                .compile(reg);
        Matcher matcher = regEx2.matcher(str);
        if (matcher.find()) {
            System.out.println("valid");
        } else {
            System.out.println("invalid");
        }
    }
}

但是我没有得到预期的结果。我可以得到合适的正则表达式吗？

十字军

也许您可以将代码与另一个获得“％”计数的表达式进行编译

 public static void main(String[] args) {
     String reg = "%Warning: portfast should only be enabled on ports connected to a single\n host. Connecting hubs, concentrators, switches, bridges, etc. to this\n interface when portfast is enabled can cause temporary bridging loops.\n Use with CAUTION";
     String str = "%Warning: portfast should only be enabled on ports connected to a single\n host. Connecting hubs, concentrators, switches, bridges, etc. to this\n interface when portfast is enabled can cause temporary bridging loops.\n Use with CAUTIONTest is a testData is invalid%";
     Pattern regEx2 = Pattern.compile(reg);
     Matcher matcher = regEx2.matcher(str);
     int occurences = str.length() - str.replace("%", "").length();

     if (matcher.find() && occurences <= 1) {
        System.out.println("valid");
     } else {
        System.out.println("invalid");
     }

 }

如果您有StringUtils类，则可以使用其方法countMatches

本文收集自互联网，转载请注明来源。

如有侵权，请联系[email protected] 删除。