12
 7

The trim() Method

Leading and trailing spaces can be removed from a string by using the trim() method of class String. For example,

"    143   ".trim()

is

"143"

This is useful in correcting some slightly defective input files. Here is the sample program with this enhancement:

import java.io.*;
class AddTwo
{
  public static void main ( String[] args ) throws IOException
  {
    int numberA, numberB;

    String line;
    BufferedReader stdin = new BufferedReader( 
        new InputStreamReader( System.in ) );

    System.out.println("Enter first number:");
    line      = stdin.readLine();
    numberA   = Integer.parseInt( line.trim() );

    System.out.println("Enter second number:");
    line      = stdin.readLine();
    numberB   = Integer.parseInt( line.trim() );

    System.out.println( "Sum: " + (numberA + numberB) );
  }
}

This will not solve all problems, however. Here is a highly defective input file:

12
seven