How to convert an IP string to an array of integers in java?

Question

I'm trying to make an array of integers from an IP string in java. For example:

String ip = "192.168.0.1";
int[] ipArray = new int[4];
int[0] = 192; int[1] = 168; int[2] = 0; int[3] = 1;

any idea how can I do this?

I know the parseInt tool, but how can I work with the "." ?

Sorry the noob question, I'm still a beginner.

Answer 1

Split your string by . sign. Solution using Java 8 Streams :

int[] ipArray = Arrays.stream(ip.split("\\."))
                .mapToInt(Integer::valueOf)
                .toArray();

EDIT

Integer::parseInt might be better here as it returns primitive int instead of Integer like Integer::valueOf does. So to avoid unnecessary unboxing :

int[] ipArray = Arrays.stream(ip.split("\\."))
                .mapToInt(Integer::parseInt)
                .toArray();

Answer 2

You can use the String.split() method.

For example:

String str = "192.168.0.1";
String[] strSplit = str.split("\\.");
int[] intArray = new int[strSplit.length];
for(int i=0; i<intArray.length; i++){
    intArray[i] = Integer.parseInt(strSplit[i]);
}

The reason for \\\\. is because . is a special character in Java Regex Engine . Otherwise if the string was split with brackets, then str.split("-") would be sufficient.