Parametrized Method in Java: try-catch does not catch ClassCastException (on Android)

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Consider creating a new Object and casting it to String within a try-catch block that catches an Exception. Everything seems to be ok. But what does happen if we cast an Object to T within similar try-catch block in a parametrized function? The exception is not catched and the program crashes raising a ClassCastException.

class test
{
    Log.i("", String.format("====== CLASS CAST TEST ======"), true);
    Log.i("", String.format("====== REGULAR CAST TEST "));
    final String test1 = test.regularCastTest(); // the exception thrown is catched within the     method
    Log.i("", String.format("====== PARAMETRIZED CAST TEST "), true);
    final String test2 = test.<String>parametrizedCastTest(); // fails here with     ClassCastException without catching it
    Log.i("", String.format("------ CLASS CAST TEST END --"), true);

    static <T> T parametrizedCastTest()
    {
        Object obj = new Object();
        try
        {
            final T ret = (T) obj;
            Log.d("", String.format("%s; %s",     obj.getClass().getSimpleName(), ret.getClass().getSimpleName())); // does not fail and prints 'Object; Object'
            return ret;
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }

        return null;
    }

    static String regularCastTest()
    {
        Object obj = new Object();
        try
        {
            final String ret = (String) obj;
            return ret;
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        return "";
    }
}

PS: the parametrized method does not fail if we simply call it without getting the result like:

test.<String>parametrizedCastTest();

asked 2 mins ago

atomontage

1

Parametrized Method in Java: try-catch does not catch ClassCastException (on Android)