Sams Teach Yourself C in 21 Days

A Simple Demonstration ..............................................................................

Before continuing with the details of class definitions, it is a good idea to see how to cre-

ate and use a simple class. This Java project will have two files. One, SimpleClass.java,

will define a very simple class that does nothing more than provide two properties, one

to store a number and the other to store some text. The second file,

ClassBasicsDemo.java, is a program that makes use of SimpeClass. The source code for

these two files is shown in Listings B5.1 and B5.2.

LISTINGB5.1 Code in SimpleClass.java

1: import java.lang.String;

2:

3: public class SimpleClass {

4:

5: public double data;

6: public String text;

7: }

LISTINGB5.2 Code in ClassBasicsDemo.java

1: public class ClassBasicsDemo {

2: public static void main(String args[])

3: {

4: SimpleClass MyClass;

5:

6: MyClass = new SimpleClass();

7: MyClass.data = 1.2345;

8: MyClass.text = “A class act.”;

9: System.out.print(“The number stored in MyClass is “);

10: System.out.println(MyClass.data);

11: System.out.print(“The text stored in MyClass is “);

12: System.out.println(MyClass.text);

13: }

14: }

The number stored in MyClass is 1.2345

The text stored in MyClass is A class act

726 Bonus Day 5

Just as with C++ member variables, you should make property variables pri-

vate and create two function to access it—one to get its value and one to

set is value.

Note

OUTPUT

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