Mockito throw Exception

Question

@Test(expectedExceptions=DataAccessException.class)
public void testUpdateSubModuleOrderDateExceptionCheck() {
    //some code to initialize//
    UserSubModuleDao userSubModuleDao = mock(UserSubModuleDao.class);
    userModuleServiceImpl.setUserSubModuleDao(userSubModuleDao);
    UserSubModule userSubModule=new UserSubModule();
    UserSubModuleId userSubModuleId=new UserSubModuleId();
      when(userSubModuleDao.findById(any(UserSubModuleId.class),eq(false))).thenThrow(DataAccessException.class);

    userModuleServiceImpl.updateSubModuleOrder(data, moduleSysId, userId);

I want to throw the Db exception for code coverage . its working if i give expected exception as : Exception.class but not for DataAccessException.class

My method in original class is as following:

public void updateSubModuleOrder(Long[] data, Long moduleSysId, Long userId) {
    try {

        for (int i = 0; i < data.length; i++) {
            SubModule subModule=new SubModule();
            subModule.setSubModuleId(data[i]);
            UserSubModuleId userSubModuleId = new UserSubModuleId();
            userSubModuleId.setSubModuleId(subModule);
            userSubModuleId.setUserId(userId);
            userSubModuleId.setUserModuleId(moduleSysId);
            UserSubModule userSubmodule = new UserSubModule();
            userSubmodule = userSubModuleDao.findById(userSubModuleId,
                    false);
catch (DataAccessException ewmsDataExp) {
        LOGGER.error(
                "Database Exception while updateSubModuleOrder because of {}",
                ewmsDataExp.getMessage());
        throw new EWMSServiceException(
                "Database Exception while updateSubModuleOrder"
                        + ewmsDataExp.getMessage());
    } catch (Exception exp) {
        LOGGER.error(
                "System Exception while updateSubModuleOrder because of {}",
                exp.getMessage());
        throw new EWMSServiceException(
                "Database Exception while updateSubModuleOrder"
                        + exp.getMessage());
    }*

i get the error

FAILED: testUpdateSubModuleOrderDateExceptionCheck
org.testng.TestException: 
**Expected exception org.springframework.dao.DataAccessException but got    org.testng.TestException:** 
**Expected exception org.springframework.dao.DataAccessException but got         java.lang.InstantiationError: org.springframework.dao.DataAccessException**
    at org.testng.internal.Invoker.handleInvocationResults(Invoker.java:1497)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:1245)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:127)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:111)
at org.testng.TestRunner.privateRun(TestRunner.java:767)
at org.testng.TestRunner.run(TestRunner.java:617)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:334)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:329)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:291)
at org.testng.SuiteRunner.run(SuiteRunner.java:240)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1224)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1149)
at org.testng.TestNG.run(TestNG.java:1057)
at org.testng.remote.RemoteTestNG.run(RemoteTestNG.java:111)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:204)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:175)

and some error lines....

Default test

Tests run: 1, Failures: 1, Skips: 0

===============================================

===============================================

Solution 1

Change this:

thenThrow(DataAccessException.class)

to

thenThrow(new DataAccessException("..."){ })

Example:

when(userSubModuleDao.findById(any(UserSubModuleId.class),eq(false))).thenThrow(new DataAccessException("..."){});

You can only pass a Class reference when that Exception type has a No-Arg constructor, and the Spring exception does not have one.

Solution 2

Try

Mockito.doThrow(new Exception()).when(mockedObject).methodName(...);

Solution 3

As stated by Jen S:

You can only pass a Class reference when that Exception type has a No-Arg constructor, and the Spring exception does not have one.

My solution was using Mockito:

Mockito.when(mockedObject.method(Mockito.anyString())).thenThrow(Mockito.mock(DataAccessException.class));

Comments

[Dawood ibn Kareem]

Why are you expecting a DataAccessException when your class explicitly catches DataAccessException and converts it to something else?

[user2375298]

it says DataAccessException cannot be instantiatied

[Jen S.]

Yes, it says the class cannot be instantiated because it tries to use a no-arg constructor to make it. And the class has no such constructor.

[wanovak]

DataAccessException is an abstract class, so you can't instantiate it. You can use new DataRetrievalFailureException("reason") instead

[Saurabh Patil]

This is a more correct answer because when...thenThrow doesn't work with the methods that return void.

[Udit Kumawat]

it is still giving errors..."java.lang.AssertionError: Expected exception: org.springframework.dao.DataAccessException"...even I have used 'new DataAccessException("..."){}'

[b15]

Worked for me, +1, but what is that { } doing?

[PAA]

@SaurabhPatil - How will you solve the issue where void method throws exception?

[Saurabh Patil]

@PAA Do you mean to say you want void method to throw an exception during testing? Yes that's exactly the reason why this answer is better than the other one.

[Prakruti Pathik]

very helpful and quick solution.. Thanks