Never executed - never tested!

Code samples I'll publish in this post are not fakes: they come from real code, released into production.

And they are not only brilliant samples of never tested code: they are samples of never executed code!!! Indeed there are in these code snippets execution path which ever - ever! - fail. Read to believe...

Sample #1 - NullPointerException at each catch execution

MyClass result = null;
try {
    result = callMethod(...);

} catch(Exception e) {    // throws ever NullPointerException...
    result.registerException(e);
}

Sample #2: ArrayIndexOutOfBoundException at each catch execution

try {
    result = callSomeMethod(...);
} catch(Exception e) {
    String[] messages = new String[3];
    messages[0] = ... ;
    messages[1] = ... ;
    messages[2] = ... ;

    // throws ever ArrayIndexOutOfBoundException ...

    messages[3] = ... ; 

    throw new CustomException(messages);
}

Sample #3: ClassCastException whenever if condition is verified

public class AClass {

    ...

    public void aMethod(final Object obj) {
        ...
        if(!obj instanceof InterfaceXYZ) {
            final InterfaceXYZ xyz = (InterfaceXYZ)obj;
            ...
        }
        ...
    }
}