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Thread: Manual Memory Management

  1. #1
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    Question Manual Memory Management

    How can one allocate an object in a function with a new command and add it to a list, and keep it even after the function returns?
    To be more precise, here is the C++ equivalent:
    void myfunction()
    {
    MyClass* myobject = new MyClass(...);
    mylist.add(myobject);
    }
     
    void someOtherFunction()
    {
    MyClass* myobject = mylist.at(2); // The object has not been deleted
    }

    At some point, I would simply call
    delete myobject;
    to deallocate my object when I wouldn't need it anymore

    I tried doing the same with Java, but my object must be getting deleted when the function terminates because I get a null reference exception
    void myfunction()
    {
    MyClass object = new MyClass();
    mylist.add(object);
    }

    Does anyone know the way I can do this in Java? Also, how can I delete the object?


  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Manual Memory Management

    how can I delete the object?
    You can't. The garbage collector takes care of recovering dead objects.

    keep it even after the function returns?
    If there is a reference to the object in some variable or list outside of the method, the object will be retained.

    my object must be getting deleted when the function terminates because I get a null reference exception
    Please post the full text of the error message and a small program that compiles, executes and shows the problem. Your explanation does not make sense. Something else is happening.
    If you don't understand my answer, don't ignore it, ask a question.

  3. #3
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    Default Re: Manual Memory Management

    Thank you Norm

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