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Change the object instance type

 
mesagir sajib
Greenhorn
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[Added code tags - see UseCodeTags]


can anyone clarify this topic.
 
Matthew Brown
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Hi Mesagir. Welcome to the Ranch!

What exactly is your question? Is it about what's happening on line 11? That's a cast. It doesn't actually change the type of the object, but it changes the type of the reference. Without that cast, you couldn't assign the results to a MyClass variable - the compiler would prevent it. Using the cast is telling the compiler "I know that elementAt says it's returning an Object, but I know it's really returning a MyClass, so treat it like that". The JVM then throws an exception at runtime if that isn't actually true.

Using generic collections (e.g an ArrayList<MyClass>) avoids this.
 
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