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Avoid making a copy reference of an object

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What is the best way to copy an object?
Using obj2 = obj1 would change the values in obj1 when I change them in obj2.

I do not want the second object to be a reference to the first object. Changes in object2 should not change object1.

Is the interface Cloneable the best way to do this?
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You can make a copy constructor so that your code becomes

obj2 = new MyObject(obj1);

You then just implement the MyObject(MyObject o) constructor to perform the copy in whatever way is appropriate for your class.
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there's a 100 answers to "which way is best", and the only correct ones include "it depends"

there's a lot written about it, you should be able to find by searching a bit,

in the mean time, the copy constructor above is a minimally invasive way to get a copy,
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