Generic data type conversion method

Question

This question is in response to another question by opensas: building a generic initializer function in java

From his question it became clear that he needs to conve

Answer 1

I am not aware of any library, however the code is just one line.

Apart from Date, all boxed primitives have a String construtor, so this method does the trick:

public static  O convert(I input, Class outputClass) throws Exception {
    return input == null ? null : outputClass.getConstructor(String.class).newInstance(input.toString());
}

To cater for Dates, you could use instanceof within the method, but I would recommend a separate method, since converting dates is a format- and context-sensitive thing (eg String-->Date parses and uses which format?, Long-->Date sets the time).

I have deliberately left error/special handling to the reader as an exercise.