Java Programming Helper

JAVA

Getting Started:

Output, Main Method:

1.  Write a statement that prints  Hello, world to the screen.

System.out.println("Hello, world") ;

2.  Write a complete main  method that prints  Hello, world to the screen.

public static void main (String[] args)

     {

          System.out.println("Hello, world") ;

     }

3.  Suppose your name was Alan Turing. Write a statement that would print your last name, followed by a comma, followed by a space and your first name.

System.out.println("Turing, Alan") ;

4.  Suppose your name was George Gershwin. Write a complete main method that would print your last name, followed by a comma, followed by a space and your first name.

public static void main (String[] args)

     {

          System.out.println("Gershwin, George") ;

     }

More Output:

1.  Given an integer variable count, write a statement that displays the value of  count on the screen.  Do not display anything else on the screen -- just the value of count.

Example:  If the value of count were 194, then:

194

(with no other characters) would be displayed on the screen.

System.out.println(count);

2.  Given a floating point variable fraction , write a statement that displays the value of  fraction on the screen.  Do not display anything else on the screen-- just the value of fraction.

Example:  If the value of fraction were 2.667, then the output of your code would be:

2.667

on a line by itself (with no other characters).

System.out.println(fraction) ;

3.  The exercise instructions here are LONG -- please read them all carefully. If you see an internal scrollbar to the right of these instructions, be sure to scroll down to read everything.

 Given an integer variable i and a floating-point variable f, that have already been given values, write a statement that writes both of their values to standard output in the following format:

i=value-of-i f=value-of-f

System.out.println("i="+i+" f="+f) ;

Declarations:

Basics:

1.  Declare a variable populationChange, suitable for holding numbers like -593142 and 8930522.

int populationChange ;

2.  Declare a variable x, suitable for storing values like 3.14159 and 6.02E23.

double x ;

Initialization:

1.  Declare an integer variable cardsInHand and initialize it to  13.

int cardsInHand = 13;

2.  Declare a variable temperature and initialize it to  98.6.

Instructor's notes:  Declaring floating-point numbers can be done with either type float or type double.  Of the two, you should use double, since it gives you more precision.

double temperature = 98.6;

3.  Declare a variable  precise and initialize it to the value  1.09388641.

double precise = 1.09388641;

Programs:

1.  Write a complete program whose class name is Hello and that displays Hello, world on the screen.

public class Hello

{

     public static void main (String[] args)

     {

          System.out.println("Hello, world");

     }

}