Java Regular Expression verification IP Address

There are many expressions for verifying IP addresses using regular expressions on the Internet. You can search a large number of expressions and write them on your own. However, it is very troublesome and troublesome. It is inevitable that someone else will write a bug. I found a few tests. I don't know any bugs or even the correct IP addresses. Many of them are still vowed, as if I had tested them myself. Today, I found a regular expression for comparison, but there is also a small bug (no error is reported when the * number is used). Package des; import java. util. RegEx. matcher;
Import java. util. RegEx. pattern; public class IP {/**
* @ Param ARGs
*/
Public static void main (string [] ARGs ){
// Todo auto-generated method stub
Ip p = new IP ();
String II = "127.0.0.1 ";

String II2 = "127.0.0 .";
String ii3 = "127.0.0.1000 ";
String ii4 = "256.0.0.1 ";
String ii5 = "127.0.0.gg ";
String ii6 = "127. h.0.1 ";
String ii7 = "127.555.0.1 ";
String ii8 = "127.00.0.1 ";
String ii9 = "127.0.04.1 ";
String ii10 = "127.100. #. 1 ";
String ii11 = "127. *. 0.1 ";
String ii12 = "127.0.0.000 ";

String ii13 = "192.168.3.12 ";

P. ismatches (II );
P. ismatches (II2 );
P. ismatches (ii3 );
P. ismatches (ii4 );
P. ismatches (ii5 );
P. ismatches (ii6 );
P. ismatches (ii7 );
P. ismatches (ii8 );

P. ismatches (ii9 );
P. ismatches (ii10 );
P. ismatches (ii11 );
P. ismatches (ii12 );
P. ismatches (ii13 );

}
Public Boolean ismatches (string IP ){
Boolean flag = false;
Try {
// String RegEx = "[0-9] + [.] [0-9] + [.] [0-9] + [.] [0-9] + ";
String RegEx = "^ (\ d | [1-9] \ d | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5] | [*]) \\.) {3} (\ d | [1-9] \ d | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5] | [*]) $ ";
// The correct one is // string RegEx = "^ (\ d | [1-9] \ d | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5]) \\.) {3} (\ d | [1-9] \ d | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5] | [*]) $ ";
// String RegEx = "\ B ((?! \ D) \ D + | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5]) \\. ((?! \ D) \ D + | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5]) \\. ((?! \ D) \ D + | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5]) \\. ((?! \ D) \ D + | 1 \ D \ d | 2 [0-4] \ d | 25 [0-5]) \ B ";
Pattern P = pattern. Compile (RegEx );
Matcher M = P. matcher (IP );
If (M. Find ()){
System. Out. println ("successss ");
Return true;
} Else {
System. Out. println ("falsss ");
}
} Catch (exception e ){
E. printstacktrace ();
}
Return flag;
}
} Output successss
Falsss
Falsss
Falsss
Falsss
Falsss
Falsss
Falsss
Falsss
Falsss
Successss
Falsss
Successss
The last 3rd are incorrect, but the output is successful.