Throwable class has two subclasses: Error and Exception. Take a look at the inheritance tree of the OutOfMemoryError class. Also, check if you should catch such an error and if you do, what you can or cannot do.
Keep in mind that an OutOfMemoryError (OOME) indicates that the JVM doesn't have enough memory for some operation. This can very well mean that your code will cause another OOME, because it's quite likely there still isn't enough memory.