Java constructors assingning value to variable and then interchanging them
Hi
>Whats should be the output of the following code and why?
>the output turned out to be 131713.Below is the code. the object >references are interchanging so the values are changing.
enter code here
public class Test { int age; String name;
Test(int age,String name){
this.age=age;
this.name=name;
} public static void main(String[] args){
Test t1 = new Test(17,"A");
Test t2 = new Test(13,"B");
Test t3 = new Test(14,"C");
t3=t2;
t2=t1;
t1=t3;
System.out.print(t1.age);
System.out.print(t2.age);
System.out.print(t3.age);
}
}
Changing the value of a reference variable doesn't modify anything inside the object that it refers to. But it can make that variable refer to a different object. The variables exist independently of the objects. This can be visualised as in the following diagrams.
After you create your three objects, you have a situation like this.
/ / /
| | | | | |
t1-> | 17 A | t2-> | 13 B | t3-> | 14 C |
| | | | | |
/ / /
Then you change what t3 refers to, so you have
/ / /
| | t2-> | | | |
t1-> | 17 A | | 13 B | | 14 C |
| | t3-> | | | |
/ / /
Then you change what t2 refers to, so you have
/ / /
t1-> | | | | | |
| 17 A | t3-> | 13 B | | 14 C |
t2-> | | | | | |
/ / /
And you change what t1 refers to, so you have
/ / /
| | t1-> | | | |
t2-> | 17 A | | 13 B | | 14 C |
| | t3-> | | | |
/ / /
Then you start printing stuff. As shown in the final diagram above, t1.age and t3.age are both 13 , and t2.age is 17 .
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