String userData = "     745   ";
String fixed;

fixed = userData.trim();

The trim() Method

The trim() method creates a new String. The new String contains the same characters as the old one but has any whitespace characters (blanks, tabs, and several other non-printing characters) removed from both ends (but not from the middle). So, for example, after the last statement. . .

String userData = "     745   ";
String fixed;

fixed = userData.trim();

. . .the new String referenced by fixed will contain the characters "745" but not the surrounding spaces.

(Usage Note:) This method is very useful. Extraneous spaces on either end of user input is a common problem.

String dryden = "   None but the brave deserves the fair.   " ;
System.out.println( dryden.trim() );