Hello Geoffery,
At the risk of adding an "I agree" reply, James and Scott are absolutely correct. Your example is a really good illustration that
Java's type checking extends to arrays as well as "standard" class types.
When the compiler evaluates a .java file, it checks that all variable assignments are type compatible throughout the file. This prevents us from assigning a reference to an incompatible object... a java.util.Date object to a java.lang.String reference, for example.
The same compiler check applies to arrays... Java recognizes that int[] is a different class type than int[][], so will generate a compiler error in your example. However, both are subclasses of Object, so we CAN assign an array to an object using a standard "widening" conversion.
Steve