why does List.toArray() return Object[] and not String[]? how to work around this?

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You need to pass in an array so its runtime type can be used as a hint by toArray. Try toArray(new String[0]) instead. You can also pass in a pre-sized array.

To understand, consider what type erasure would have to do to make

new T[4]

work. If Java allowed that, the best it could do post erasure is

new Object[4]

Most toArray implementations use java.lang.reflect.Array to construct an output array of the right type given a type hint passed as a Class.

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