特殊规则IP验证

IP校验 不能以0、127及224-255开头；是正确的IP

public class IpReg {
	
	public static void main(String[] args) {
		String s = "225.255.255.255";
		
		boolean b = false;
		//只要捕获到了异常，说明Ip是非法的，根据需要处理异常
		try {
			b = validateIP(s);
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println("验证结果为 :"+b);
	}
	
	public static boolean validateIP(String ip){
		boolean b = false;
		String[] ips = ip.split("\\.");
		if(ips.length!=4){
			throw new IllegalArgumentException("Illegal IP ["+ip+"]");
		}
		
		//对第一组进行验证
		String[] ips1 = ips[0].split("");
		if(ips1.length>4){
			throw new IllegalArgumentException("Illegal IP ["+ip+"],String ["+ips[0]+"] given that length must less than 4");
		}
		
		int fip = 0;
		try {
			fip = Integer.parseInt(ips[0]);
		} catch (NumberFormatException e) {
			throw new IllegalArgumentException("Illegal IP ["+ip+"],param ["+ips[0]+"] given must be type of number!");
		}
		//如果没有抛出异常，则全部是数字，进行判断是否合法
		if(fip<0 | fip == 0 | fip == 127){
			throw new IllegalArgumentException("Illegal IP ["+ip+"], can not begin with "+fip);
		}else{
			b = true;
			for(int i=224;i<=255;i++){
				if(fip==i){
					throw new IllegalArgumentException("Illegal IP ["+ip+"], can not begin with "+fip);
				}
			}
		}
		//对剩下的三组进行验证
		boolean b2 = validate(ips[1]);
		boolean b3 = validate(ips[2]);
		boolean b4 = validate(ips[3]);
		
		return b&b2&b3&b4;
	}
	
	private static boolean validate(String subip){
		String[] ips = subip.split("");
		if(ips.length>4){
			throw new IllegalArgumentException("Illegal IP ["+subip+"],String ["+subip+"] given that length must less than 4");
		}
		Integer ip = null;
		
		try {
			ip = Integer.parseInt(subip);
		} catch (NumberFormatException e) {
			throw new IllegalArgumentException("Illegal IP ["+subip+"],param ["+ips[0]+"] given must be type of number!");
		}
		//如果没有抛出异常，则全部是数字，进行判断是否合法
		if(ip<=255 && ip>-1){
			return true;
		}else{
			throw new IllegalArgumentException("Illegal IP ["+subip+"],param ["+subip+"] given that must less than 256 and great than -1");
		}
	}
}

由于对正则表达式不熟悉，以及时间原因，所以上面这是比较笨的方法，解决问题还是得自己细心，用心，精心，好多问题真的是只要自己稍微花点时间用下心，用点时间，用点力就可以解决得了！下面是正则表达式:

String str_pattern = "^(((?!127)([1-9]|[1-9]\\d|1\\d\\d|2[0-1]\\d|22[0-3]))\\.)(([0-9]|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])\\.){2}([0-9]|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])$";
Pattern pattern = Pattern.compile(str_pattern);
String ip ="127.127.127.245";
Matcher m = pattern.matcher(ip);
boolean b = m.find();
if(b){
    System.out.println(m.group());
}else{
    System.out.println(b);
}

评论

4 楼 tigerl 2012-01-05  

直接用正则表达式也可以，但是写正则表达式比较麻烦，测试也麻烦，不是所有的验证都需要正则表达式！只要能满足需求，又不影响性能，写什么都可以！

3 楼 jyjava 2012-01-05  

直接用正则表达式，减去所有麻烦，再说你这个该是前台用js吧

2 楼 tigerl 2012-01-05  

你验证过你的正则表达式吗？我是验证如下的：
IP校验 不能以0、127及224-255开头；是正确的IP

1 楼 gaowei52306 2012-01-05  

正则表达式：IP校验
        String strPattern =
            "^(([0-9]|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])\\.)" + "{3}([0-9]|[1-9]\\d|1\\d\\d|2[0-4]\\d|25[0-5])$";