java判断是否是ip

java判断是否是ip

java采用正则判断字符串是否是ip的方法如下：

1、Java源码

import java.util.regex.Matcher;
import java.util.regex.Pattern;


public class IpAddress {
    public static class IpAdd {
        public boolean isIP(String addr) {
            if (addr.length() < 7 || addr.length() > 15 || "".equals(addr)) {
                return false;
            }
            
            String rexp =
                "([1-9]|[1-9]\d|1\d{2}|2[0-4]\d|25[0-5])(\.(\d|[1-9]\d|1\d{2}|2[0-4]\d|25[0-5])){3}";

            Pattern pat = Pattern.compile(rexp);

            Matcher mat = pat.matcher(addr);

            boolean ipAddress = mat.find();

            return ipAddress;
        }
    }
}

2、使用

public static void main(String[] args) {
    
    String oneAddress = "10.127.30.45";
    
    String twoAddress = "127.30.45";
    
    String threeAddress = "7.0.4";
    
    String fourAddress = "255.255.255.2567";

    IpAdd ipAdd = new IpAdd();

    //判断oneAddress是否是IP  
    System.out.println(ipAdd.isIP(oneAddress));

    //判断twoAddress是否是IP  
    System.out.println(ipAdd.isIP(twoAddress));

    //判断threeAddress是否是IP  
    System.out.println(ipAdd.isIP(threeAddress));

    //判断fourAddress是否是IP  
    System.out.println(ipAdd.isIP(fourAddress));
}

3、运行结果

true
false
false
false

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