java - 从 Java 中的字符串中删除 IP 地址

Question

有什么方法可以从字符串中删除 IP 吗？

我们获得的输入文件有时会将 IP 附加到用户名，例如

Jan vd MerwePiet Breedt (172.166.23.41)Jan vd Merwe (164.23.23.51)Sarel Fourie (23.12.167.244)Piet Breedt

所以如果有IP，我想删除它。我一直在研究很多函数，但似乎无法正确获取索引和参数。

Answer 1

您可以查找 ( 并删除剩余的字符串。

public class Main {

    public static void main(String[] args) {

        String[] names = { "Jan vd Merwe", 
                           "Piet Breedt (172.166.23.41)",
                           "Jan vd Merwe (164.23.23.51)", 
                           "Sarel Fourie (23.12.167.244)" };

        for (String name : names) {

            int parIndex = name.indexLastOf('(');
            if (parIndex != -1)
                name = name.substring(0, parIndex-1);

            System.out.println(name);
        }
    }
}

打印:

Jan vd Merwe
Piet Breedt
Jan vd Merwe
Sarel Fourie

<小时/>

另一种解决方案，基于正则表达式:

    String[] names = { "Jan vd Merwe", 
                       "Piet Breedt (172.166.23.41)",
                       "Jan vd Merwe (164.23.23.51)", 
                       "Sarel Fourie (23.12.167.244)" };

    String ipExp = "\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}";
    Pattern pattern = Pattern.compile("(.*?)\\s*(\\(" + ipExp + "\\))?");

    for (String nameIp : names) {
        Matcher m = pattern.matcher(nameIp);
        if (m.matches()) {
            String name = m.group(1);
            String ip = m.group(2) == null ? "n/a" : m.group(2);
            System.out.printf("Name: %s, Ip: %s%n", name, ip);
        }
    }

打印

Name: Jan vd Merwe, Ip: n/a
Name: Piet Breedt, Ip: (172.166.23.41)
Name: Jan vd Merwe, Ip: (164.23.23.51)
Name: Sarel Fourie, Ip: (23.12.167.244)