This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 4 years ago.
I have the following test code for a class:
/**
* Test Class
*/
public class GeneratorTestTest {
private Generator generator;
private static BufferedImage testImage;
private BufferedImage rotatedImageTestResult;
#Before
public void setUp() throws Exception {
generator = new Generator(null, 0);
File inputFile = new File("src/test/resource/picture.jpg");
testImage = ImageIO.read(inputFile);
}
/**
* Test method
*/
#Test
public void testRotateImageRotateImage() {
//Line 39
rotatedImageTestResult = generator.rotateImage(testImage, 0);
assertTrue(imageEquals(testImage, rotatedImageTestResult));
}
I am get a NullPointerException on the Test method when I try to run it. How can I pass the Junit test?
Here is a full log of the Exception:
line 39 is "rotatedImageTestResult = generator.rotateImage(testImage, 0);
rotatedImageTestResult = generator.rotateImage(testImage, 0);
On this line of code either "generator" is null or some helper object in your generator is null so the "rotateImage" method itself is throwing the null pointer exception.
Related
When I try to test a spring cloud stream function based method, it always happens NullPointerException about InputDestination.
I have two questions:
It's hard for me to know how to write UT from the official doc. official test doc
Besides, how to write integration Test if test file has some dependencies. It seems create a new context and always has NoSuchBeanDefination error.
I have tried as flow, but the context can not find some dependency beans.
#Test
public void sampleTest() {
try (ConfigurableApplicationContext context = new SpringApplicationBuilder(
TestChannelBinderConfiguration.getCompleteConfiguration(
MyTestConfiguration.class))
.run("--spring.cloud.function.definition=uppercase")) {
InputDestination source = context.getBean(InputDestination.class);
OutputDestination target = context.getBean(OutputDestination.class);
source.send(new GenericMessage<byte[]>("hello".getBytes()));
assertThat(target.receive().getPayload()).isEqualTo("HELLO".getBytes());
}
}
So I just want to write UT, but still have NPE.
Here is my code.
#Bean
public Function<Message<List<DemoBean>>, Message<DemoBean>> findFirstBean( ){
return message -> {
List<DemoBean> demoBeans = message.getPayload();
return MessageBuilder.withPayload(demoBeans.get( 0 )).build();
};
}
Here is my test.
#SpringBootTest
#ActiveProfiles(profiles = "local")
#Import({ TestChannelBinderConfiguration.class})
class FunctionDemoTest {
#Autowired
private InputDestination inputDestination;
#Autowired
private OutputDestination outputDestination;
private FunctionDemo functionDemo;
// some dependency need to mock
private DemoService demoService;
#BeforeEach
void setUp() {
demoService = Mockito.mock( DemoService.class );
functionDemo = new FunctionDemo( demoService);
}
#Test
public void findFirstBeanTest() {
DemoBean demoBean = new DemoBean();
demoBean.setName("Howard");
demoBean.setAge( 1 );
DemoBean demoBean1 = new DemoBean();
demoBean1.setName("Frank");
demoBean1.setAge( 2 );
List<DemoBean> demoBeanList = new ArrayList<>();
demoBeanList.add( demoBean );
demoBeanList.add( demoBean1 );
Message<List<DemoBean>> inputMessage = MessageBuilder.withPayload(demoBeanList).build();
inputDestination.send(inputMessage,"findFirstBean-in-0");
Assertions.assertNotNull( outputDestination.receive( 10000, "findFirstBean-out-0") );
}
}
Here is error:
java.lang.NullPointerException: while trying to invoke the method org.springframework.messaging.SubscribableChannel.send(org.springframework.messaging.Message) of a null object returned from org.springframework.cloud.stream.binder.test.InputDestination.getChannelByName(java.lang.String)
at org.springframework.cloud.stream.binder.test.InputDestination.send(InputDestination.java:89)
at com.successfactors.caf.listener.FunctionDemoTest.raePdrResultProcessor(FunctionDemoTest.java:82)
Well, I know the root cause of NPE.
Message<byte[]> receive(long timeout, String bindingName)
It seems should be destinationName instead of bindingName in source code.
Any other answers would be appreciated.
I wrote simple method that executes tests in my test classes: DataContainerTest.class, AnotherTest.class.
public static void main(String [] args) throws Exception {
Result result = JUnitCore.runClasses(DataContainerTest.class, AnotherTest.class);
System.out.println(result.getRunCount());
System.out.println("Total number of tests " + result.getRunCount());
System.out.println("Total number of tests failed: " + result.getFailureCount());
for(Failure failures : result.getFailures()){
System.out.println(failures.getMessage());
}
System.out.println(result.wasSuccessful());
}
This method doesn't work for my another class CommandsTest.class, where i'm using annotation #RunWith(PowerMockRunner.class). See output below:
1
Total number of tests 1
Total number of tests failed: 1
No runnable methods
false
Here is the sample of the CommandsTest.class
#RunWith(PowerMockRunner.class)
#PrepareForTest({Helper.class,
UtilsPlatform.class,
SessionManager.class,
DataContainerTest.class,
FieldObserver.class,
android.util.Log.class})
public class CommandsTest {
private static Commands2 commands;
private static License mockedLicense;
private static HSQL hsql;
#BeforeClass
public static void setUpStatic() throws Exception {
commands = new Commands2();
PowerMockito.mockStatic(UtilsPlatform.class);
PowerMockito.when(UtilsPlatform.isTablet()).thenReturn(true);
PowerMockito.mockStatic(android.util.Log.class);
PowerMockito.mockStatic(FieldObserver.class);
PowerMockito.doNothing().when(FieldObserver.class, "put", Mockito.anyInt(),
Mockito.anyInt(), Mockito.anyInt(), Mockito.anyInt(), Mockito.any(Session.class));
hsql = PowerMockito.mock(HSQL.class);
PowerMockito.when(hsql, "OnCaseOpen", Mockito.anyInt(), Mockito.anyInt(),
Mockito.anyInt()).thenReturn(false);
mockedLicense = PowerMockito.mock(License.class);
}
#Before
public void setUp() throws Exception {
PowerMockito.mockStatic(SessionManager.class);
PowerMockito.mockStatic(Helper.class);
PowerMockito.doNothing().when(Helper.class, "writeToFile", Mockito.anyString(),
Mockito.any(SocketException.class));
PowerMockito.when(Helper.class, "getLicense").thenReturn(mockedLicense);
PowerMockito.doNothing().when(Helper.class, "fieldOpened", Mockito.anyString(), Mockito.anyString());
}
#Test
public void sendKeyCombinationEventTest_nullParameters_returnOne(){
Assert.assertEquals(1, commands.sendResponse());
}
#Test
public void sendKeyCombinationEventTest_registredGuisNotNullAndOneIsLocal_returnOne(){
Assert.assertEquals(1, commands.sendKeyCombinationEvent());
}
While pressing run button in AndroidStudio, all tests are passed but my own TestRunner cannot run tests in this class.
The best way to handle classes using #RunWith(PowerMockRunner.class) annotation is just put them into default test source of your android project and then run all tests via gradle test. You don't actually need to write own test runner.
testclass.java
#Test
public void testgetDictionaryValueListById() {
DictionaryValue dictionaryValue = new DictionaryValue();
dictionaryValue.setId(1);
dictionaryValue.setValueName("Test Dictionary Value");
dictionaryValue.setValueKey("12345678");
dictionaryValue.setStatus("Active");
dictionaryValue.setCreatedOn(new Date());
dictionaryValue.setUpdatedOn(new Date());
Mockito.when(dictionaryValueRepo.findById(1).get()).thenReturn(dictionaryValue);
assertThat(dictionaryService.getDictionaryValueListById(1)).isEqualTo(dictionaryValue);
}
Service.java
public DictionaryValue getDictionaryValueListById(int id) {
return dictionaryValueRepo.findById(id).get();
}
Repo.java
#Repository
public interface DictionaryValueRepo extends JpaRepository<DictionaryValue, Integer> {
}
I am getting no such value present again and again on executing test case in testclass.java. I don't know why? but when I am running my service method from the controller it is working as expected - fetching records from the database but not working in a test case.
Your test should be like this and please check out the naming. You need to Mock the step findId() befor the `get().
#InjectMocks
Service cut;
#Mock
DictionaryValueRepo dictionaryValueRepoMock;
// Can skipped by adding a #RunWith... on Testclass
#Before
public init() {
Mockito.initMocks(this);
}
#Test
public void testgetDictionaryValueListById() {
// Prepare Data
final int testId = 1;
DictionaryValue dictionaryValue = new DictionaryValue();
dictionaryValue.setId(testId);
dictionaryValue.setValueName("Test Dictionary Value");
dictionaryValue.setValueKey("12345678");
dictionaryValue.setStatus("Active");
dictionaryValue.setCreatedOn(new Date());
dictionaryValue.setUpdatedOn(new Date());
// config mocking
Mockito.when(dictionaryValueRepo.findById(testId)).thenReturn(<VALUE>);
Mockito.when(dictionaryValueRepo.findById(testId).get()).thenReturn(dictionaryValue);
// Call yout method for Testing
cut.getDictionaryValueListById(testId);
// verifies (if wanted) + assertions....
}
I concur with LenglBoy, so the right answer should be given to him.
The thing you need to be careful is what "VALUE" means in this line:
Mockito.when(dictionaryValueRepo.findById(testId)).thenReturn(VALUE);
The findById returns an Optional, so that is what you should build and pass to Mockito. Something like this:
Mockito.when(dictionaryValueRepo.findById(testId))
.thenReturn(Optional.ofNullable(dictionaryValue));
And for a scenario where the id does not exists in BD, passing Optional.empty() should be good enough.
I am having trouble to test correctly a thrown exception (Is it a namspacing problem).
Here is my custom exception:
<?php
namespace Example\Customexception;
class ResourceNotAvailableException extends \Exception {}
Here the class I am testing:
namespace Example\Lib;
use Example\Customexception\ResourceNotAvailableException;
class Configuration {
private static $instance;
private $arrConfig;
private function __construct($configFile)
{
$this->arrConfig = parse_ini_file($configFile, true);
if ($this->arrConfig == false){
throw new ResourceNotAvailableException("Config file {$configFile} not available.");
}
}
public static function getInstance($configFile = "config/config.ini")
{
if (self::$instance == null){
try {
self::$instance = new Configuration($configFile);
}
catch(ResourceNotAvailableException $e) {
throw $e;
}
}
return self::$instance;
}
}
And here is my test class:
use Example\Lib\Configuration;
class ConfigurationTest extends PHPUnit_Framework_TestCase {
/**
* #expectedException Example\Customexception\ResourceNotAvailableException
*/
function testGetInstanceThrowsException()
{
$configuration = Configuration::getInstance("configtestini");
}
}
And here is the output I get:
PHPUnit 5.3.2 by Sebastian Bergmann and contributors.
E 1 / 1 (100%)
Time: 89 ms, Memory: 2.75Mb
There was 1 error:
1) ConfigurationTest::testGetInstanceThrowsException
parse_ini_file(configtestini): failed to open stream: No such file or directory
/home/me/workspace/codeexample/src/Lib/Configuration.php:24
/home/me/workspace/codeexample/src/Lib/Configuration.php:39
/home/me/workspace/codeexample/tests/unit/Lib/ConfigurationTest.php:14
FAILURES!
Tests: 1, Assertions: 0, Errors: 1.
Please ignore the line numbers in the output because I removed some comments from the code to make it easily readable here.
Thanks
parse_ini_file() raises an error which is turned into an exception by PHPUnit's error handler.
My problem is as follows:
I am trying to test multiple unit-tests in my controller in a Play Framework 2.4 application. I figured out I need to use a FakeApplication to run the FakeRequests to my controllers in, but for some odd reason the unit-tests work if I start and stop a new FakeApplication. If I start and stop the same FakeApplication, the first unit-test with a FakeRequest works, and the rest dont.
My question:
What am I doing wrong? Why are my unit-tests working if I start and stop a new FakeApplication, and why are they not working if I start and stop the same FakeApplication?
Here is my code snippet:
UnitTest class:
#Test
public void submitTestCorrectInput() {
final String input = CORRECT_INPUT;
final Result result = doCall(input);
assertThat(result.status(), is(equalTo(Http.Status.OK)));
}
#Test
public void submitTestIncorrectInput() {
final String input = INCORRECT_INPUT;
final Result result = doCall(input);
assertThat(result.status(), is(equalTo(Http.Status.NOT_FOUND)));
}
private Result doCall(final String input, final String max, final String filter) {
final Http.RequestBuilder requestBuilder = Helpers.fakeRequest(routes.Application.submit(input));
return route(requestBuilder);
}
Superclass from unittest class:
#Before
public void setUp() {
Play.start(Helpers.fakeApplication().getWrappedApplication());
}
#After
public void tearDown() {
Play.stop(Helpers.fakeApplication().getWrappedApplication());
}