Callable and Supplier
– never shall the two meet!?

Let’s say we have this clever little legacy API method:

Now, we discover Java 8’s neat Supplier functional interface. As a courtesy to our users, we decide we would like to accept those as well. Does this work? A naïve addition gives us:

So far so good? Well, what happens if we try […]

A case for == on Class objects

Sending around Class objects can be useful in some cases. Most people don’t know or bother declaring them with types, and that can work too. I recently encountered code like this; the method choose was supposed to take Class objects belonging to a certain class hierarchy, and they used .equals() to find what class object […]

Ugly multiple inheritance in Java

Let’s say we have two classes:

Let’s imagine that the methods are really big and complex and for some horrid reason we want to inherit from both classes.