Computer Science 121
Example using if-else

// Application that gives advice for patient with a fever.

import java.io.*;
import java.text.*;

public class MedicalAdvice
{
    public static void main (String [] args)
    {
        Advice advice = new Advice ();
        advice.readData ();
        advice.classifyTemperature ();
    } // method main
} // class MedicalAdvice

class Advice
{
    private int temperature = 0;

    public void readData ()
    {
        System.out.print ( "Enter your temperature. ");
        try
        {
            BufferedReader stdin = new BufferedReader (new InputStreamReader (System.in));
            temperature = Integer.parseInt (stdin.readLine ());
        }
        catch (IOException e) { System.out.println ("I/O error");}
        catch (NumberFormatException ex) { System.out.println ("Number format error.");}
    } // method readData

    // Method to analyse a patient's temperature.
    public void classifyTemperature ()
    {
        if (temperature >= 105)
            System.out.println ( "Medical emergency, go to the hospital." );
        else if (temperature >= 101)
            System.out.println ( "High temperature, see a doctor." );
        else if (temperature >= 99)
            System.out.println ( "Mild fever, take two aspirin and go to bed." );
        else if (temperature >= 97)
            System.out.println ( "Temperature normal." );
        else
            System.out.println ( "Your temperature is low, take a warm bath." );
    } // classifyTemperature
} // class Advice