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Tag: interface

How to cast an object of an ArrayList of objects (of type superclass) to an object of type subclass

If I have a superclass, let’s call it Car, with the constructor parameters String name, String color, double wheelSize, and a subclass of this, let’s call it Truck, with the constructor parameters String name, String color, double wheelSize, and double truckBedArea, and in the subclass (Truck), I have a method called modifyCar with the paramaters Car car, String newName, String

Can you change the Type of Java Exception’s error message?

I’m writing an Internal-Facing tool with a very slow runtime. Because of this runtime I’m trying to validate the input for errors and send a JSON object with a detailed list of every missing or failing element to the client before actually running the tool. I was wondering if there was a way to modify java Exception’s error message return

What’s the meaning of this line of code? And how can I create an object of this class?

I was trying to construct an object of the MTree class (https://github.com/Waikato/moa/blob/master/moa/src/main/java/moa/clusterers/outliers/utils/mtree/MTree.java) The constructor of MTree looks like this: The DistanceFunction here is an interface, the code of it is: And it’s implementation is: And my first question is what’s the meaning of return new DistanceFunction<Data>() in the method public static <Data> DistanceFunction<Data> cached(final DistanceFunction<Data> distanceFunction) [the method is in