how to extract numeric values from input string in java

Question

How can I extract only the numeric values from the input string?

For example, the input string may be like this:

String str="abc d 1234567890pqr 54897";

I want the numeric values only i.e, "1234567890" and "54897". All the alphabetic and special characters will be discarded.

Answer 1

String str=" abc d 1234567890pqr 54897";
Pattern pattern = Pattern.compile("\\w+([0-9]+)\\w+([0-9]+)");
Matcher matcher = pattern.matcher(str);
for(int i = 0 ; i < matcher.groupCount(); i++) {
  matcher.find();
  System.out.println(matcher.group());
}

Answer 2

You could use the .nextInt() method from the Scanner class:

Scans the next token of the input as an int.

Alternatively, you could also do something like so:

String str=" abc d 1234567890pqr 54897";

Pattern p = Pattern.compile("(\\d+)");
Matcher m = p.matcher(str);
while(m.find())
{
    System.out.println(m.group(1));
}