Answer:
public static String onlyDigits(String in){
String digitsOnly = in.replaceAll("[^0-9]", "");
return digitsOnly;
}
A Complete program is wrtten in the explanation section
Explanation:
public class TestClass {
public static void main(String[] args) {
String a = "-jaskdh2367sd.27askjdfh23";
System.out.println(onlyDigits(a));
}
public static String onlyDigits(String in){
String digitsOnly = in.replaceAll("[^0-9]", "");
return digitsOnly;
}
}
The output: 23672723
The main logic here is using the Java replaceAll method which returns a string after replacing all the sequence of characters that match its argument, regex with an empty string
