Page 285 - Introduction to Programming with Java: A Problem Solving Approach
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Figure 7.3
CarDriver class that drives Car class in Figure 7.2
Doing this overlays johnCar’s previous reference to John’s original Car object, and that Car object be- comes inaccessible to the program (abandoned), like Car object #1 is in this picture:
johnCar Car object #1
7.3 Assigning a Reference 251
1 /********************************************************
2 *
CarDriver.java
Dean & Dean
This class demonstrates copying an object.
6 ********************************************************/
3 *
4*
5 *
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8 public class CarDriver
9{
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public static void main(String[] args)
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{
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Car johnCar = new Car();
Car stacyCar;
johnCar.setMake("Honda");
johnCar.setYear(2003);
johnCar.setColor("silver");
stacyCar = johnCar.makeCopy();
stacyCar.setColor("peach");
System.out.println("John's car:");
johnCar.display();
System.out.println("Stacy's car:");
stacyCar.display();
Apago PDF Enhancer
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}
// end main
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}
// end class CarDriver
Output:
John's car:
make= Honda
year= 2003
color= silver
Stacy's car:
make= Honda
year= 2003
color= peach
This assigns the returned reference to a reference variable in the calling method.
stacyCar Car object #2
