Extract digits from string - StringUtils Java

Question

I have a String and I want to extract the (only) sequence of digits in the string.

Example: helloThisIsA1234Sample. I want the 1234

It\'s a given that the s

Answer 1

I've created a JUnit Test class(as a additional knowledge/info) for the same issue. Hope you'll be finding this helpful.

   public class StringHelper {
    //Separate words from String which has gigits
        public String drawDigitsFromString(String strValue){
            String str = strValue.trim();
            String digits="";
            for (int i = 0; i < str.length(); i++) {
                char chrs = str.charAt(i);              
                if (Character.isDigit(chrs))
                    digits = digits+chrs;
            }
            return digits;
        }
    }

And JUnit Test case is:

 public class StringHelperTest {
    StringHelper helper;

        @Before
        public void before(){
            helper = new StringHelper();
        }

        @Test
    public void testDrawDigitsFromString(){
        assertEquals("187111", helper.drawDigitsFromString("TCS187TCS111"));
    }
 }