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As you saw in the last section you can connect “if” statements with “else” statements. You can connect these into long ladders. This allows you to process several different options. Listing 5.5 shows an if/else ladder.

Listing 5.5: If/Else Ladder (NumberIf.java)

import java.io.*;

class NumberIf
{
  public static void main(String args[])
  {
    try
    {
      InputStreamReader inputStreamReader = 
        new InputStreamReader ( System.in );
      BufferedReader in = 
        new BufferedReader ( inputStreamReader );
      System.out.print(
        "Enter a number between 1 and 5? ");
      String num = in.readLine();
      int number = Integer.parseInt(num);

      if( number==1 )
      {
        System.out.println("You entered One.");
      }
      else if( number==2 )
      {
        System.out.println("You entered Two.");
      }
      else if( number==3 )
      {
        System.out.println("You entered Three.");
      }
      else if( number==4 )
      {
        System.out.println("You entered Four.");
      }
      else if( number==5 )
      {
        System.out.println("You entered Five.");
      }
      else
      {
        System.out.println(
       "You did not enter a number between 1 and 5.");
      }
    }
    catch(NumberFormatException e)
    {
      System.out.println(
        "You must enter a valid number.");
    }
    catch(IOException e)
    {
    }
  }
}

This program asks you to enter a number. For numbers 1-5 it will print out the word form of the number. For example it will print out “one” if you enter “1”. This is done with an if/else ladder.