Java Basics 1.05

Switch Statements: Integers

Code:

import java.io.BufferedReader;

import java.io.InputStreamReader;

 

public class SwitchWithInts {

 

   public static void main(String[] args) {

      String input = getInput("Enter a number between 1 and 12: ");

      int month = Integer.parseInt(input);

      

      switch (month) {

      case 1:

            System.out.println("The month is January");

            break; //must use break to leave switch

      case 2:

            System.out.println("The month is February");

            break;

      case 3:

            System.out.println("The month is March");

            break;

      default:

            break;

      }

   }

  

   private static String getInput(String prompt) {

      BufferedReader stdin = new BufferedReader(

                 new InputStreamReader(System.in));

 

      System.out.print(prompt);

      System.out.flush();

      

      try {

            return stdin.readLine();

      } catch (Exception e) {

            return "Error: " + e.getMessage();

      }

   }

 

}

 

 

 

 

Switch Statements: Enums

Project > New > Enum

 

 

Code:

public enum Month {

   JANUARY, FEBRUARY, MARCH; //Constants of enum class

}

 

 

public class SwitchWithEnums {

   // Enumerations

   public static void main(String[] args) {

 

//    int month = 1;

      Month month = Month.FEBRUARY;

      

      switch(month) {

      case JANUARY:

            System.out.println("It's the first month");

            break;

      case FEBRUARY:

            System.out.println("It's the second month");

            break;

      case MARCH:

            System.out.println("Its the third month");

      }

 

   }

 

}

 

 

Switch Statements:  Strings (Java SE7)

 

Loops

 

Code:

public class Main {

 

   static private String[] months =

      {"January", "February", "March",

      "April", "May", "June",

      "July", "August", "September",

      "October", "November", "December"};

 

   public static void main(String[] args) {

 

      // using counter variables instead of complex objects

//    for (int i = 0; i < months.length; i++) {

//          System.out.println(months[i]);             

//    }

 

      // For each month in the months[] array

//    for (String month : months) {

//          System.out.println(month);

//    }

 

      // eval BEFORE loop

//    int counter = 0;

//    while (counter < months.length) {

//          System.out.println(months[counter]);

//          counter ++;

//    }

 

      // eval AFTER loop

      int counter = 0;

      do {

            System.out.println(months[counter]);

            counter ++;

      } while (counter < months.length);

   }

}