String.replace not working

Question

I am trying to replace the "X" in this String with another char by sending it to a method...

This is the String I'm sending:

adress = "http://developer.android.com/sdk/api_diff/X/changes.html";
//Caliing method
getadress(adress,i)

and this is the method:

private static String getadress(String stadress, Integer i) {
 stadress.replaceAll("X",i.toString());
 System.out.print(stadress);
 return stadress;
}

The method doesn't work for me and I guess it's because I'm not using it correctly.

What I was trying to do:

adress.replace("X","2"); //for example ...

Answer 1

Methods that operate on Strings return the changed result; they do not modify the original String. Change

stadress.replaceAll("X",i.toString());

to

stadress = stadress.replaceAll("X",i.toString());

Answer 2

You almost had it right. You just need to update the stadress variable with the new value:

private static String getadress(String stadress, Integer i) {
 stadress = stadress.replaceAll("X",i.toString());//assign with new value here
 System.out.print(stadress);
 return stadress;
}

Or, as a shorter way of achieving this:

private static String getadress(String stadress, Integer i) {
 return stadress.replaceAll("X",i.toString());//assign with new value here on one line
 //System.out.print(stadress);
 //return stadress;
}