Out of my mind (list may be incomplete, and is too long to fit in a comment), I would say: use exceptions when checking parameters passed to public or protected methods and constructors use exceptions when interacting with the user or when you expect the client code to recover from an exceptional situation use exceptions … Read more
If you launch your program with -enableassertions (or -ea for short) then this statement assert cond; is equivalent to if (!cond) throw new AssertionError(); If you launch your program without this option, the assert statement will have no effect. For example, assert d >= 0 && d <= s.length();, as posted in your question, is … Read more
Assert.Throws returns the exception that’s thrown which lets you assert on the exception. var ex = Assert.Throws<Exception>(() => user.MakeUserActive()); Assert.That(ex.Message, Is.EqualTo(“Actual exception message”)); So if no exception is thrown, or an exception of the wrong type is thrown, the first Assert.Throws assertion will fail. However if an exception of the correct type is thrown then … Read more
You could use the @Rule annotation with ExpectedException, like this: @Rule public ExpectedException expectedEx = ExpectedException.none(); @Test public void shouldThrowRuntimeExceptionWhenEmployeeIDisNull() throws Exception { expectedEx.expect(RuntimeException.class); expectedEx.expectMessage(“Employee ID is null”); // do something that should throw the exception… System.out.println(“=======Starting Exception process=======”); throw new NullPointerException(“Employee ID is null”); } Note that the example in the ExpectedException docs is … Read more
Asserts should be used to test conditions that should never happen. The purpose is to crash early in the case of a corrupt program state. Exceptions should be used for errors that can conceivably happen, and you should almost always create your own Exception classes. For example, if you’re writing a function to read from … Read more
The assert statement exists in almost every programming language. It has two main uses: It helps detect problems early in your program, where the cause is clear, rather than later when some other operation fails. A type error in Python, for example, can go through several layers of code before actually raising an Exception if … Read more