I want to know that whether this test case should pass or fail
beacause
expected = IndexOutOfBoundsException.class
and actually it is throwing Arithmatic exception. can anyone explain?
#Test(expected = IndexOutOfBoundsException.class)
public void testDivideNumbers()throws ArithmeticException{
try{
double a = 10/0;
fail("Failed: Should get an Arithmatic Exception");
}
catch (ArithmeticException e) {
}
}
To test that the correct exception is thrown you should not have the test method throw the exception but just have the test itself result in the thrown exception.
So if ArithmeticException is expected then the test should be:
#Test(expected = ArithmeticException.class)
public void testDivideNumbers() {
double a = 10/0;
}
It should fail because it doesn't throw any exception; the ArithmeticException is caught and swallowed by the catch block.
This test is expecting to get an IndexOutOfBoundsException thrown. Because that does not happen in the test, the test fails. You can "fix" the test like this:
#Test(expected = IndexOutOfBoundsException.class)
public void testDivideNumbers() {
try {
double a = 10/0;
Assert.fail("Failed: Should get an Arithmetic Exception");
}
catch (ArithmeticException e) {
// Assert that this exception is thrown as expected
Assert.assertEquals("/ by zero", e.getMessage());
}
throw new IndexOutOfBoundsException();
}
You should not leave the catch block empty. You should always put some assert in it proving that the fail() didn't happen and the catch did happen and, importantly, happened for the reason you expected.
Related
I try to test my Exception JUnit and the test doesn't pass I have this error trace :
org.mockito.internal.runners.JUnit45AndHigherRunnerImpl.run(JUnitAndHigherRunnerImpl.java:37)
and
org.mockito.runners.MockitoJUnitRunner.run(MockitoJUnitRunner.java:62)
and here is my code :
PatientEntityFacade pef = new PatientEntityFacade();
Mockito.when(pef.findByNumber(5555)).thenReturn(patientEntity);
#Rule
public ExpectedException thrown = ExpectedException.none();
#Test
public void shouldThrow() throws PatientNotFoundException
{
thrown.expect(PatientNotFoundException.class);
thrown.expectMessage("personalized exception no patient found");
try {
pef.findByNumber(5555);
} catch (com.patient.facade.PatientNotFoundException e) {
e.printStackTrace();
}
}
If you watn to test your Exception, then do it the right way.
Define when Exception should be thrown.
in #BeforeClass if every Method should
in #Test-method if only this Method should throw it.
Notice, that you can use any(X.class) if other methods got other values for it.
Don´t try-catch in unit-tests.
Catch it this way and if there is no Exception, the test will fail.
#Test(expected = PatientNotFoundException.class)
public void shouldThrow()
pef.findByNumber(5555);
}
in my Junit tests I have a test case that must be fail only when IOexception is throwing by my object under test.
So ,if my object under test throw IllegalStateException (or other Error or Exception) my test case is OK but if my object under test throw IOexception my test case must be fail.
How can I do it ?
Thanks for all.
You can use the expected exception rule
#Rule
public ExpectedException expected = new ExpectedException();
#Test
public void doSomethingWithNoIOException() {
// we expect an exception that's NOT an instance of IOException
// you'll need to static import the hamcrest matchers referenced below
expected.expect(not(instanceOf(IOException.class));
// call the method under test
callSomething();
}
As you want to fail when exception is NOT an IOException, You can do that by catching the IOException and asserting with fail() like below:
#Test
public void yourTestScenario() {
try {
//code that throws IOException and other Exceptions
} catch(IOException ioexe) {
Assert.fail();
} catch(Exception exe) {
//Ignore
}
}
I have a method with a handled exception:
public boolean exampleMethod(){
try{
Integer temp=null;
temp.equals(null);
return
}catch(Exception e){
e.printStackTrace();
}
}
I want to test it
public void test_exampleMethod(){}
I have tried
#Rule
public ExpectedException expectedException=ExpectedException.none();
public void test_exampleMethod(){
expectedException.expect(JsonParseException.class);
exampleMethod();
}
but that doesnt work because the exception is handled inside.
I also tried
#Test(expected=JsonParseException.class)
but same issue...the exception is handled
I know that I can just do
assertTrue(if(exampleMethod()))
but it will still print the stack trace to the log. I would prefer clean logs...Any suggestions?
You cannot test what a method is doing internally. This is completely hidden (unless there are side effects, that are visible outside).
The test can check that for a specific input the method returns a expected output. But you can not check, how this is done. So you have no way to detect if there was a exception that you have handled.
So: either don't handle the exception (let the test catch the exception), or return a special value that tells you about the exception.
Anyway, I hope your real exception handling is more sensible than in your example.
If the method does not throw an exception you cannot expect to get one!
Below an example how write a Junit Test for a method that throws an Exception:
class Parser {
public void parseValue(String number) {
return Integer.parseInt(number);
}
}
Normal test case
public void testParseValueOK() {
Parser parser = new Parser();
assertTrue(23, parser.parseValue("23"));
}
Test case for exception
public void testParseValueException() {
Parser parser = new Parser();
try {
int value = parser.parseValue("notANumber");
fail("Expected a NumberFormatException");
} catch (NumberFormatException ex) {
// as expected got exception
}
}
In my ServiceStack service, I throw an exception that has an inner exception. When I caught a WebServiceRequest on the client side, the ErrorCode was the inner exception type name.
This is bad for me because it doesn't allow me to respond to the specific exception type that was thrown on the server.
I'm failing to see why ServiceStack was designed this way. It's pretty typical to catch lower level exceptions and wrap them with more informative and sometimes end-user friendly exceptions.
How can I change the default behavior so it uses the surface level exception and not the inner-most?
After looking at the first example at https://github.com/ServiceStack/ServiceStack/wiki/Error-Handling, I decided to check out at DtoUtils.HandleException, which looks like this:
public static object HandleException(IResolver iocResolver, object request, Exception ex)
{
if (ex.InnerException != null && !(ex is IHttpError))
ex = ex.InnerException;
var responseStatus = ex.ToResponseStatus();
if (EndpointHost.DebugMode)
{
// View stack trace in tests and on the client
responseStatus.StackTrace = GetRequestErrorBody(request) + ex;
}
Log.Error("ServiceBase<TRequest>::Service Exception", ex);
if (iocResolver != null)
LogErrorInRedisIfExists(iocResolver.TryResolve<IRedisClientsManager>(), request.GetType().Name, responseStatus);
var errorResponse = CreateErrorResponse(request, ex, responseStatus);
return errorResponse;
}
The very first instruction replaces the exception with it's inner exception. I'm not sure what the the thinking was with that. It seems counter intuitive to me and so I just re-implemented the method in my AppHost class, removing that first if statement block:
public override void Configure(Container container)
{
ServiceExceptionHandler += (request, exception) => HandleException(this, request, exception);
}
/// <remarks>
/// Verbatim implementation of DtoUtils.HandleException, without the innerexception replacement.
/// </remarks>
public static object HandleException(IResolver iocResolver, object request, Exception ex)
{
var responseStatus = ex.ToResponseStatus();
if (EndpointHost.DebugMode)
{
// View stack trace in tests and on the client
responseStatus.StackTrace = DtoUtils.GetRequestErrorBody(request) + ex;
}
var log = LogManager.GetLogger(typeof(DtoUtils));
log.Error("ServiceBase<TRequest>::Service Exception", ex);
if (iocResolver != null)
DtoUtils.LogErrorInRedisIfExists(iocResolver.TryResolve<IRedisClientsManager>(), request.GetType().Name, responseStatus);
var errorResponse = DtoUtils.CreateErrorResponse(request, ex, responseStatus);
return errorResponse;
}
This is obviously not ideal, since I had to copy a bunch of code that is totally unrelated to the problem that I had with the original implementation. It makes me feel like I have to maintain this method whenever I update ServiceStack. I would love to here of a better way to accomplish this.
Anyway, I have the exception handling that I like in my client code:
catch (WebServiceException ex)
{
if (ex.ErrorCode == typeof (SomeKindOfException).Name)
{
// do something useful here
}
else throw;
}
It doesn't seem like you'll have to maintain a bunch of code. You're writing one method to implement your own error handling. You could try calling DtoUtils.HandleException(this, request, exception) in your own method and modify the HttpError object returned. Not sure you have access to change all properties/values you're looking for.
public static object HandleException(IResolver iocResolver, object request, Exception ex)
{
HttpError err = (HttpError)DtoUtils.HandleException(this, request, ex);
err.Reponse = ex.InnerException;
}
I am facing a very peculiar situation. I am using hibernate template with spring 3.0.5 for DB operations. When I try to insert a User model the first time, a DataAccessException is thrown, which I catch. Now I wish to retry the same DB operation for say 3 times. The second time when it, no exception is thrown.
Here is the code:
package com.user.profile.dao;
#Repository("userProfileDAOImpl")
public class UserProfileDAOImpl implements IUserProfileDAO {
#Autowired
private HibernateTemplate hibernateTemplate;
public Long insertUserProfileData(User user) throws AppNonFatalException {
Long id = null;
int retryCount = 0;
while (retryCount < 3) {
try {
id = (Long)hibernateTemplate.save(user);
}
catch (DataAccessException e) {
e.printStackTrace();
retryCount++;
System.out.println("Retry Count = " + retryCount);
if (retryCount > 3) {
throw new AppNonFatalException(e.getLocalizedMessage(), "10000", e.getMessage(), e);
}
}
catch (Exception e) {
/* not coming inside this block too second time onwards */
System.out.println("Pure Exception");
}
}
return id;
}
}
I read that RuntimeExceptions should not be caught. Then how do I retry the operation. Should I retry at the service layer? Am I missing something? Any help is appreciated.
From https://community.oracle.com/docs/DOC-983543:
Unchecked exceptions are exceptions
that do not need to be declared in a
throws clause. They extend
RuntimeException. An unchecked
exception indicates an unexpected
problem that is probably due to a bug
in the code.
Since DataAccessException is a RuntimeException, you might want to check what is the real cause of the exception and fix it instead of catching it and retry the operation.