What does // Note: Solution requires vector to be saved as an integer-array mean? I can't see that that would be required in the solution

• Please don't use assertTrue() for assertions unless the tested function returns a boolean because it results in confusing assertion messages. Use assertEquals(), also the variant with a delta for norm().
• Catching exceptions and only writing to System.out will actually not fail the test. You could use assertDoesNotThrow() but it might not mix well with nested assertions.