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Thread: Question on String class

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    Default Question on String class

    Hi, I know that to create an object we use the new keyword which then makes the variable a reference variable.

    Are String variables already objects? if so how if we dont use the new keyword, and why have they implemented the String class to do this, thanks.


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    Default Re: Question on String class

    There are String variables and there are String objects.
    String aStr; // define a String variable (it has a null value)
    aStr = "A string"; // give the variable a value
    Strings are handled differently in a shortcut manner so that you are not required to use new.
    Strings are used a lot in programs so the authors decided to make it easier to use them.

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    Default Re: Question on String class

    At what point does a String variable become an object?

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    Default Re: Question on String class

    A variable is always a variable. Class variables (as opposed to primitives) can either have a null value or a reference to(address of) an object.
    They "point" to the object.

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    Default Re: Question on String class

    ok, can you answer me two things please:

    At what point does a class variable (example: String example have a reference to an object?

    Also, can you tell me is there a point in having a class variable with a null value, is this not pointless?

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    Default Re: Question on String class

    At what point does a class variable (example: String example have a reference
    When it is assigned one. That is true of all variables. They do not have values until assigned one.

    point in having a class variable with a null value, is this not pointless?
    Most of the time yes. But you don't always know what value you are going to assign a variable at the time you define it. You define it so other code can see it (its definition is in scope), later you give it a value when you know what value you want it to have.

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    Default Re: Question on String class

    Thanks for replying, but what im asking is how are String objects handled differently so that we do not need to use the new keyword?

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    Default Re: Question on String class

    The compiler takes care of the details.

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    Default Re: Question on String class

    Thank you

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