Berkeley CSUA MOTD:Entry 19871
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2025/05/28 [General] UID:1000 Activity:popular
5/28    

2000/11/21 [Computer/SW/Languages/C_Cplusplus, Computer/SW/Languages/Java] UID:19871 Activity:very high
11/21   All java class inherites from class *Object*, if I have three classes
        A, B, and C all have one same method showErr().  If I want to have a
        function that can call showErr() depending on the object that I passed
        in, eg.
                public void handleErr(Object o) {
                        o.showErr();
                }
        This code won't compile because Object doesn't have method showErr();
        Question is is this possible?  Type casting won't work because we don\
        don't the object type at compile time.  I don't think c/c++ can do th\
                          It works fine in C++: _/

                          template<typename T> void handleErr(T *object) {
                              object->showErr();
                          }

                          You don't need to create an interface, and you don't
                          need to use run-time type checking; it just works.
        In Java, there's Object.getClass(), however I don't think it'll help
        here...Does anyone know if the above code can be tweaked to work?
        \_ use an interface
           \_ I guess you could have A, B & C implement the interface but
              you can be more hacker style with instanceof and casting.

              if (o instanceof A) {
                ((A)o).showErr();
              } else if (o instanceof B) {
                ((B)o).showErr();
              ...
              \_ That's not hacker style, that's tjb l4m3r-style.
                 Use reflection.  -pld
                     \_ is reflection available in 1.0 or 1.1?
                 \_ how dare you call me a l4m3r you lu53r. - tjb
                 \_ how dare you call me a l4m3r U 1u53r. - tjb
                 \_ dumbass, if it works, I should get 100% for it.
                    It's about getting it to work, not showing off your
                    "elite" style.  -tjb #1 fan
                    \_ whatever happened to the effort to get tjb
                       a soda account?
2025/05/28 [General] UID:1000 Activity:popular
5/28    

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        \_ C is still more popular than C++?  I feel much better about myself
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