My application have several execution modes, and in 1 mode it is normal that some of my tests will throw a concrete exception. I need to annotate this methods with something like #SkipOnFail that will set method as skipped if exception was thrown.
thanks in advance!
#Edit(for my question to be more clear)
#Test(expected=ConcreteException.class)
does not work for me because i need my tests to pass even if ConcreteException.class was not thrown(expected tag in junit will mark my test as failed if this exception won't be thrown), and to be skipped otherwise. In all other cases it should work as always.
#Solution that worked for me(junit v4.7) thx to #axtavt
#Rule
public MethodRule skipRule = new MethodRule() {
public Statement apply(final Statement base, FrameworkMethod method, Object target) {
if(method.getAnnotation(SkipOnFail.class) == null) return base;
return new Statement() {
#Override
public void evaluate() throws Throwable {
try{
base.evaluate();
} catch (ConcreteException e) {
Assume.assumeTrue(false);
}
}
};
}
};
#Thx
I don't think that such a feature is available out of the box, but it should be pretty easy to implement with custom TestRule and Assume, something like this:
#Rule
public TestRule skipRule = new TestRule() {
public Statement apply(final Statement base, Description desc) {
if (desc.getAnnotation(SkipOnFail.class) == null) return base;
return new Statement() {
public void evaluate() throws Throwable {
try {
base.evaluate();
} catch (MyExceptoion ex) {
Assume.assumeTrue(false);
}
}
};
}
};
What about using JUnit Extensions?
The following example is taken from their Tutorial.
It provides aditional annotations for Prerequisites (#Prerequisite): Ignore tests based on conditions.
The required approach would be to check this during running tests. So you can simply add a #Prerequisite(requires="") annotation.
public class TestFillDatabase {
#Prerequisite(requires = "databaseIsAvailable")
#Test public void fillData() {
// ...
}
public boolean databaseIsAvailable() {
boolean isAvailable = ...;
return isAvailable;
}
}
public class TestFillDatabase {
#Prerequisite(requires = "databaseIsAvailable")
#Test public void fillData() {
// ...
}
public boolean databaseIsAvailable() {
boolean isAvailable = ...;
return isAvailable ;
}
}
This specified methods with #Prerequisite(requires = "databaseIsAvailable") must be a public method, returning a boolean or Boolean value.
If these methods will be consolidated in helper classes, you can also specify static methods within a class to be called using #Prerequisite(requires = "databaseIsAvailable", callee="DBHelper").
public class TestFillDatabase {
#Prerequisite(requires = "databaseIsAvailable", callee="DBHelper")
#Test public void fillData() {
// ...
}
}
public class DBHelper {
public static boolean databaseIsAvailable() {
boolean isAvailable = ...;
return isAvailable ;
}
}
Also using the Assume class (since jUnit 4.4), you can use assumeNoException():
try{
base.evaluate();
} catch (ConcreteException e) {
Assume.assumeNoException("Concrete exception: skipping test", e);
}
I searched for the docs about JUnit and it appears that from version 4.9 they have introduced what they call test rules (see TestRule). You may start from this.
The ExpectedException class marked as #Rule could be of some help in order to check for exceptions thrown but not mandatory for the test to pass.
For more advanced usage I cannot say for the moment as I've just discovered it.
Related
Hello I have wrote a test cases for my logic and all these are working nicely. however, I have no idea how to test my custom exceptions. My code below;
#Component
public class PlaneFactory {
public Plane getPlane(String planeType) {
if (StringUtils.isBlank(planeType)) {
throw new PlaneTypeNotFoundException();
}
if (planeType.equalsIgnoreCase("lightJet")) {
return new LightJet();
} else if (planeType.equalsIgnoreCase("midJet")) {
return new MidJet();
}
else {
throw new InvalidPlaneTypeException();
}
my custom exceptions below;
PlaneTypeNotFoundException class below;
public class PlaneTypeNotFoundException extends RuntimeException {
private static final long serialVersionUID = 4314211343358454345L;
public PlaneTypeNotFoundException() {
super("You have not enter anything to check a plane");
}
}
InvalidPlaneTypeException below;
public class InvalidPlaneTypeException extends RuntimeException {
public InvalidPlaneTypeException() {
super("You need to enter one of following plane types : {LightJet, MidJet}");
}
}
which methods are suitable to use ? I mean in this scenario should I use assertThrows or just use expected annotations ?
for PlaneTypeNotFoundException I have tried something below which it did not work
#Test
public void testPlaneFactory_isEmptyOrNull_ThenReturnException() {
String planeType = "";
LightJet lightJet= (LightJet) planeFactory.getPlane(planeType);
assertThrows(PlaneNotFoundException.class, () -> lightJet.getType().equalsIgnoreCase(planeType), "You have not enter anything to check a plane");
}
If I follow your code correctly then the executable lambda in assertThrows() should be the code that you expect to generate the exception:
public void testPlaneFactory_isEmptyOrNull_ThenReturnException() {
assertThrows(PlaneNotFoundException.class, () -> planeFactory.getPlane(""));
}
If it does throw an exception then the test should pass.
A test for the second case would be:
void testInvalidPlaneType() {
assertThrows(InvalidPlaneTypeException.class, () -> planeFactory.getPlane("doh"));
}
I need to create a Rule to check for exceptions with customized messages. Below is my attempt, but this is not quite correct since I am simply using methods from the standard "ExpectedException". How to do it right?
public class CustomExpectedExceptionRule implements TestRule {
private final ExpectedException delegate = ExpectedException.none();
public static CustomExpectedExceptionRule none() {
return new CustomExpectedExceptionRule();
}
private CustomExpectedExceptionRule() {
}
public void expect(Class<? extends Throwable> type) {
delegate.expect(type);
}
public void expectMessage(String message) {
delegate.expectMessage(message);
}
#Override
public Statement apply(Statement base, Description description) {
return delegate.apply(base, description);
}
Now I'm trying something like that:
private final ExpectedException expectedException = ExpectedException.none();
private Object exception;
private String expectedMessage;
#Override
public Statement apply(Statement base, Description description) {
return new Statement() {
#Override
public void evaluate() throws Throwable {
expectedException.expect((Class<? extends Throwable>) exception);
expectedException.expectMessage(expectedMessage);
base.evaluate();
}
};
}
public void expectedMessage(String expectedMessage) {
this.expectedMessage = expectedMessage;
}
public void expectedException(Object exception) {
this.exception = exception;
}
But this test does not work where the exception is thrown does not pass, though all fields here are passed.
How do I remake it in the correct form?
As I understand the requirement, in your tests you need to:
public class MyTest {
#Rule
ExpectedException expExc = ExpectedException.none();
#Test
public void throwsNothing() {
// "normal tests" not affected.
}
#Test
public void throwsExceptionWithSpecificTypeAndMessage() {
expExc.expect(MyCustomException.class);
expExc.expectMessage("substring, that passes test");// other matchers possible
// do something that (is expected to) raise(s)
// MyCustomException("substring, that passes test").
}
}
..where MyCustomException.class is a custom exception class (the lowest possible in inheritance hierarchy, which you want to "pass"), and substring, that passes test the (part of) the message, which you want to "pass".
Introducing a custom TestRule saves you 1 line/Test. In this simple case I would recommend you, not to implement the interface but extend ExternalResource (, see here)):
class CustomExpectedException extends ExternalResource /*implements (!) TestRule*/ {
private ExpectedException expExc = ExpectedException.none();
/* Parameterize the message and also the class, if it fits your needs,
* alternatively && additionally implement defaults/constants/more methods.*/
public void myExpect(String substr) {
expExc.expect(MyCustomException.class);
expExc.expectMessage(substr);// other matchers possible
}
}
...and then use it like:
public class MyTest {
#Rule
CustomExpectedException expExc = new CustomExpectedException();
...
#Test
public void throwsExceptionWithSpecificTypeAndMessage() {
expExc.myExpect("substring, that passes test");
// do something...
}
}
A rule-less approach(, see here) :
public class MyTest {
#Test
public void throwsExceptionWithSpecificTypeAndMessage() {
try { // !
// do something ...
// after that, fail the test:
org.junit.Assert.fail("expected exception!");
} catch (Exception exc) { // ! here i would recommend "the highest possible Exception" (in inheritance hierarchy) ...even better <code>Throwable</code>.
// this code can be moved to a (static) util method:
if (exc instanceof MyCustomException) {
// make assertions on ((MyCustomException) exc).getMessage();
} else {
org.junit.Assert.fail("UNexpected exception!");
// or rethrow:
// throw exc;
}
}
}
}
I would like to test the return code of an exception. Here is my production code:
class A {
try {
something...
}
catch (Exception e)
{
throw new MyExceptionClass(INTERNAL_ERROR_CODE, e);
}
}
And the corresponding exception:
class MyExceptionClass extends ... {
private errorCode;
public MyExceptionClass(int errorCode){
this.errorCode = errorCode;
}
public getErrorCode(){
return this.errorCode;
}
}
My unit test:
public class AUnitTests{
#Rule
public ExpectedException thrown= ExpectedException.none();
#Test (expected = MyExceptionClass.class,
public void whenRunningSomething_shouldThrowMyExceptionWithInternalErrorCode() throws Exception {
thrown.expect(MyExceptionClass.class);
??? expected return code INTERNAL_ERROR_CODE ???
something();
}
}
Simple:
#Test
public void whenSerialNumberIsEmpty_shouldThrowSerialNumberInvalid() throws Exception {
try{
whenRunningSomething_shouldThrowMyExceptionWithInternalErrorCode();
fail("should have thrown");
}
catch (MyExceptionClass e){
assertThat(e.getCode(), is(MyExceptionClass.INTERNAL_ERROR_CODE));
}
That is all you need here:
you don't want to expect that specific exception, as you want to check some properties of it
you know that you want to enter that specific catch block; thus you simply fail when the call doesn't throw
you don't need any other checking - when the method throws any other exception, JUnit will report that as error anyway
You can check for it using hamcres matchers as long as thrown.expect is overload to receive Matcher
thrown.expect(CombinableMatcher.both(
CoreMatchers.is(CoreMatchers.instanceOf(MyExceptionClass.class)))
.and(Matchers.hasProperty("errorCode", CoreMatchers.is(123))));
Note that you will need to add hamcrest matcher to your dependencies. Core matched that are included in JUnit is not enough.
Or if you don't want to use CombinableMatcher:
thrown.expect(CoreMatchers.instanceOf(MyExceptionClass.class));
thrown.expect(Matchers.hasProperty("errorCode", CoreMatchers.is(123));
Also, you don't need (expected = MyExceptionClass.class) declaration for #Test annotation
Expanding upon Sergii's answer, you can clean this up even more by writing a custom matcher.
import org.hamcrest.Description;
import org.hamcrest.TypeSafeMatcher;
public class CustomMatcher extends TypeSafeMatcher<CustomException> {
public static CustomMatcher hasCode(String item) {
return new CustomMatcher(item);
}
private String foundErrorCode;
private final String expectedErrorCode;
private CustomMatcher(String expectedErrorCode) {
this.expectedErrorCode = expectedErrorCode;
}
#Override
protected boolean matchesSafely(final CustomException exception) {
foundErrorCode = exception.getErrorCode();
return foundErrorCode.equalsIgnoreCase(expectedErrorCode);
}
#Override
public void describeTo(Description description) {
description.appendValue(foundErrorCode)
.appendText(" was not found instead of ")
.appendValue(expectedErrorCode);
}
}
The error code can then be checked like:
import org.junit.rules.ExpectedException;
public class MyObjTest {
#Rule
public ExpectedException thrown = ExpectedException.none();
#Test
public void someMethodThatThrowsCustomException() {
thrown.expect(CustomException.class);
thrown.expect(CustomMatcher.hasCode("110501"));
MyObj obj = new MyObj();
obj.methodThatThrowsCustomException();
}
}
Reference: https://dzone.com/articles/testing-custom-exceptions
I have a class which I would like to test with a public static method that contains some chained method calls. Assuming that an exception occurs during the chained method calls, how do I handle this effectively and make it return some specific value?
Following is the code sample of the test class.
#RunWith(PowerMockRunner.class)
#PrepareForTest({CodeWithPrivateMethod.class,CodeWithAnotherPrivateMethod.class,CodeWithYetAnotherPrivateMethod.class})
public class CodeWithPrivateMethodTest {
#Test
public void when_gambling_is_true_then_always_explode() throws Exception {
CodeWithYetAnotherPrivateMethod codeWithYetAnotherPrivateMethod = PowerMockito.spy(new CodeWithYetAnotherPrivateMethod());
PowerMockito.whenNew(CodeWithYetAnotherPrivateMethod.class).withAnyArguments().thenReturn(codeWithYetAnotherPrivateMethod);
CodeWithAnotherPrivateMethod codeWithAnotherPrivateMethod = PowerMockito.spy(new CodeWithAnotherPrivateMethod());
PowerMockito.whenNew(CodeWithAnotherPrivateMethod.class).withAnyArguments().thenReturn(codeWithAnotherPrivateMethod);
PowerMockito.doReturn(true).when(codeWithYetAnotherPrivateMethod, "getGambling");
//PowerMockito.doReturn(codeWithYetAnotherPrivateMethod).when(codeWithAnotherPrivateMethod, "getGambleValue");
PowerMockito.spy(CodeWithPrivateMethod.class);
CodeWithPrivateMethod.startGamble();
}
}
Following is the code sample for the class under test
public class CodeWithPrivateMethod {
public static void startGamble() {
Boolean gamble = CodeWithAnotherPrivateMethod.getGambleValue()
.getGambling();
if (gamble) {
System.out.println("kaboom");
}else{
System.out.println("boom boom");
}
}
}
Following is the code sample for the class that gets called from the class under test
public class CodeWithAnotherPrivateMethod {
static CodeWithYetAnotherPrivateMethod codeWithYetAnotherPrivateMethod = new CodeWithYetAnotherPrivateMethod();
public static CodeWithYetAnotherPrivateMethod getGambleValue() {
return codeWithYetAnotherPrivateMethod; //works fine
return null; // fails
}
}
Following is the code sample for the other class that gets called from the class under test
public class CodeWithYetAnotherPrivateMethod {
public Boolean getGambling() {
return false;
}
}
So Assuming I return a null value from getGambleValue() method of CodeWithAnotherPrivateMethod class, how do I handle this null value effectively in my testclass?
This is how to specify expected exceptions using Mockito:
#Test(expected = NullPointerException.class)
public void when_gambling_is_true_then_always_explode() throws Exception {
...
Before I found out about this I would do:
#Test
public void when_gambling_is_true_then_always_explode() throws Exception {
// setup omitted
try {
CodeWithPrivateMethod.startGamble();
}
catch(NullPointerException e) {
// expected
return;
}
fail("Expected NullPointerException");
}
EDIT: Testing multiple classes that call each other statically like this is a severe code smell. Unit tests should test a single class and inline static calls should be limited to utility classes.
Another comment: your example class names are very confusing. Next time please stick with Foo, Bar, Baz or Appple, Pear, Banana.
If you are not getting an NPE then I expect your mocking/spying is interfering. If you call the code under test without mocking/spying the call chain would be:
CodeWithPrivateMethod.startGamble();
->
CodeWithYetAnotherPrivateMethod value = CodeWithAnotherPrivateMethod.getGambleValue();
->
return null;
<-
value.getGambling();
<- throws NullPointerException
What exactly are you trying to find out or achieve?
EDIT: Here's how it should work with PowerMock
#RunWith(PowerMockRunner.class)
#PrepareForTest(CodeWithAnotherPrivateMethod.class)
public class CodeWithPrivateMethodTest {
#Mock
private CodeWithYetAnotherPrivateMethod yetAnotherInstance;
#Test
public final void testStartGamble() {
// SETUP
mockStatic(CodeWithAnotherPrivateMethod.class);
expect(CodeWithAnotherPrivateMethod.getGambleValue())
.andReturn(yetAnotherInstance);
Boolean gamblingValue = true;
expect(yetAnotherInstance.getGambling()).andReturn(gamblingValue);
replayAll();
// CALL
CodeWithPrivateMethod.startGamble();
// VERIFY
verifyAll();
}
I have been trying to run the following test using mockito and junit and I keep on getting "java.lang.NullPointerException: name must not be null"
Can anyone tell me why this is happening?
On debugging, I found out that this exception is thrown when the test executes the following statement in isStopValid(String) method:
FacilityValidationUtil facUtil = new FacilityValidationUtil();
#RunWith(MockitoJUnitRunner.class)
public class MyFormTest{
#InjectMocks MyForm form = new MyForm();
#Mock FacilityValidationUtil facUtil;
#Test
public void testIsStopValid() throws FinderException{
when(facUtil.isFacilityValid("")).thenReturn(false);
form.setOrigin("");
assertEquals(false, form.isStopValid(form.getOrigin()));
}
}
Class with method to be tested:
public class MyForm{
FacilityValidationUtil facUtil = new FacilityValidationUtil();
public boolean isStopValid(String stop){
try {
return facUtil.isFacilityValid(stop);
} catch (FinderException e) {
log.error("Error finding the stop. "+e.getCause());
return false;
}
}
}
public class FacilityValidationUtil{
private FacilityDAO facilityDao = new HibernateFacilityDAO();
public boolean isFacilityValid(String facility) throws FinderException{
boolean test;
FacilityImpl facilityImpl = facilityDao.findFacilityByNassCode(facility);
test = (facilityImpl==null)?false : true;
return test;
}
}
public class HibernateFacilityDAO extends HibernateAbstractDeltaDAO implements FacilityDAO {
public HibernateFacilityDAO() {
super(false);
}
}
Short Answer: You are trying to mock a variable (facUtil) that is local to your isStopValid method, so the mock version of this object in your test is never going to be called because you are 'newing it up" each time.
Long Answer: It looks like you are trying to mock the call to your FacilityValidationUtil class, and if this is the case, then you need to either make the class a field so that Mockito can inject the object by reflection (if this object is thread safe, which it looks like it is) or explore a mocking framework like PowerMockito that will allow you to mock a constructor (google for PowerMockito when new).
PowerMockito.whenNew(FacilityValidationUtil.class).withNoArguments().thenReturn(facUtil);
Mockito doesn't support any mocking of constructor args by default.
EDIT
If you are still having trouble, then I would suggest starting with a smaller example. I've put together one for you that works and uses the code you are trying to test (It's using inner classes though, which Mockito has some quirky rules about, but I'm just doing it to compress the example).
#RunWith(MockitoJUnitRunner.class)
public class MyFormTest {
#InjectMocks
private MyForm form = new MyForm();
#Mock
private FacilityValidationUtil facUtil;
#Test
public void testIsStopValid_false() {
when(facUtil.isFacilityValid("")).thenReturn(false);
assertEquals(false, form.isStopValid(""));
}
#Test
public void testIsStopValid_true() {
when(facUtil.isFacilityValid("")).thenReturn(true);
assertEquals(true, form.isStopValid(""));
}
public class MyForm {
private FacilityValidationUtil facUtil = new FacilityValidationUtil();
public boolean isStopValid(String stop) {
try {
return facUtil.isFacilityValid(stop);
} catch (FinderException e) {
return false;
}
}
}
public class FacilityValidationUtil {
public boolean isFacilityValid(String facility) throws FinderException {
throw new RuntimeException(facility);
}
}
public class FinderException extends RuntimeException {
public FinderException(String message) {
super(message);
}
}
}
What's really important is that your mock is not getting injected correctly. Until you get that resolved, you are going to keep getting the same error. Set a break point in your MyForm at the point you call facUtil.isFaciltyValid and look at the object. It should be a mockito object, not your class.
Good luck.