need help in java

hello everyone, i was going through exercise in book and here is the part i need some help.

Consider this code that creates some location objects with coordinates x=10 and y=20:

Location a, b, c;
a=new Location (10,20);
b=new Location (10,20);
c=b;

after this code executes, what are the values of these boolean expressions?

A= =b
a.equals(b)
a= =c
a.equals(c)
b= =c
b.equals(c)

Comments

  • : hello everyone, i was going through exercise in book and here is the part i need some help.
    :
    : Consider this code that creates some location objects with coordinates x=10 and y=20:
    :
    : Location a, b, c;
    : a=new Location (10,20);//creates an object
    : b=new Location (10,20);//creates an object with the same values of a, but is not the same object
    : c=b;//c now refers to b ie they point to the same location in memory
    :
    : after this code executes, what are the values of these boolean expressions?

    //the boolean expressions refer to memory addresses, not the value of the object

    //equals() evaluates some value in both objects, not the references. What they return, depends on the implementation of Location
    :
    : A= =b
    : a.equals(b)
    : a= =c
    : a.equals(c)
    : b= =c
    : b.equals(c)
    :

    You can compile this code(after some modifications of course) and find out, but in short it is helping to point out that you rarely want to compare 2 objects with ==. That 2 references refer to the same object is rarely useful info. But, how they compare in relation to the object value has many important applications.


    [italic][blue]Just my 2 bits[/blue][italic]

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