How to mock private methods from Jmokit 1.49 version - junit

I am using Junit 3.8.1 and updated Jmokit to 1.49
I have a project in which existing tests present with MockUp. Having private methods mocked. After updating Jmockit jar to 1.49 version getting error as follows
java.lang.IllegalArgumentException: Unsupported fake for private method
My Java class to test is
public class Foo {
String aVar;
public Foo(String str) {
aVar = str;
}
private void concatStr(String append) {
aVar = aVar.concat(append);
}
public void doSomeTask() {
concatStr("Test");
}
}
and test class is
public class FooTest extends TestCase {
public FooTest(String testName) {
super(testName);
}
public static Test suite() {
return new TestSuite(FooTest.class);
}
public void test() {
new MockUp<Foo>() {
#Mock
private void concatStr(String append) {
Assert.assertEquals("Test", append);
}
};
Foo foo = new Foo("demoString");
foo.doSomeTask();
}
}
On console getting error as below
[INFO] Running org.test.jmokitupdate.FooTest
[ERROR] Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.028 s <<< FAILURE! - in
org.test.jmokitupdate.FooTest
[ERROR] test(org.test.jmokitupdate.FooTest) Time elapsed: 0.025 s <<< ERROR!
java.lang.IllegalArgumentException: Unsupported fake for private method
Foo#concatStr(Ljava/lang/String;)V found
at mockit.internal.faking.FakedClassModifier.visitMethod(FakedClassModifier.java:96)
at mockit.asm.methods.MethodReader.readMethodBody(MethodReader.java:118)
at mockit.asm.methods.MethodReader.readMethod(MethodReader.java:75)
at mockit.asm.methods.MethodReader.readMethods(MethodReader.java:62)
at mockit.asm.classes.ClassReader.readFieldsAndMethods(ClassReader.java:196)
at mockit.asm.classes.ClassReader.accept(ClassReader.java:89)
at mockit.internal.faking.FakeClassSetup.modifyRealClass(FakeClassSetup.java:80)
at mockit.internal.faking.FakeClassSetup.redefineMethods(FakeClassSetup.java:61)
at mockit.MockUp.redefineClass(MockUp.java:114)
at mockit.MockUp.<init>(MockUp.java:78)
at org.test.jmokitupdate.FooTest$1.<init>(FooTest.java:31)
at org.test.jmokitupdate.FooTest.test(FooTest.java:31)

Earlier versions of JMockit allowed mocking private methods, and honestly, I thought it was a brilliant differentiator with other mocking-frameworks. Sadly, more recent versions have eliminated the ability to mock privates - became a warning in 1.45 and an exception in 1.47.
There is no real official explanation, although supposition is that private methods should be so simple they do not need testing/mocking. By extension, if you are trying to access it for purposes of testing, then it should not be private. People (other than you) would likely want to also alter the behavior, and that your need to access it for test purposes is strongly suggesting the method ought to be accessible. Make it protected or package-private. FWIW, there are annotations like "#VisibleForTesting" that can be used to help indicate the intent.
So you know, 1.47 also removed the "Deencapsulation" mechanism which was one of my favorite tools for inspecting/setting private data. Painful at the time I had to convert, because it littered my test code, but in hind sight, #Tested/#Injectable (the replacement) is way cleaner. As the maintainer indicates, JMockit is not intended as a way to get at privates, there are other frameworks that do that and no sense in doing the job that they do better. I switched over to Apache's commons-lang3 (FieldUtils/MethodUtils/etc), but other frameworks exist

Related

Spring-boot Redis JMS JUnit

I am using Redis Server for message broker in my spring boot application.
Is there any simple way to Junit my publish and receive API?
e.g :
Publisher :
public String publish(Object domainObj) {
template.convertAndSend(topic.getTopic(), domainObj.toString());
return "Event Published";
}
Receiver :
public class Receiver implements MessageListener {
#Override
public void onMessage(Message message, byte[] bytes) {
System.out.println("Consumed Message {}" + message);
}
}
I am using JedisConnectionFactory and RedisMessageListenerContainer and RedisTemplate for my implementation
#Configuration
#EnableRedisRepositories
public class RedisConfig {
#Bean
public JedisConnectionFactory connectionFactory() {
RedisStandaloneConfiguration configuration = new RedisStandaloneConfiguration();
configuration.setHostName("localhost");
configuration.setPort(6379);
return new JedisConnectionFactory(configuration);
}
#Bean
public RedisTemplate<String, Object> template() {
RedisTemplate<String, Object> template = new RedisTemplate<>();
template.setConnectionFactory(connectionFactory());
template.setKeySerializer(new StringRedisSerializer());
template.setHashKeySerializer(new StringRedisSerializer());
template.setHashKeySerializer(new JdkSerializationRedisSerializer());
template.setValueSerializer(new JdkSerializationRedisSerializer());
template.setEnableTransactionSupport(true);
template.afterPropertiesSet();
return template;
}
#Bean
public ChannelTopic topic() {
return new ChannelTopic("common-channel");
}
#Bean
public MessageListenerAdapter messageListenerAdapter() {
return new MessageListenerAdapter(new Receiver());
}
#Bean
public RedisMessageListenerContainer redisMessageListenerContainer() {
RedisMessageListenerContainer container = new RedisMessageListenerContainer();
container.setConnectionFactory(connectionFactory());
container.addMessageListener(messageListenerAdapter(), topic());
return container;
}
Unit Testing Receiver and Publisher implementation is quite straight.
JUnit 5 coupled with Mockito extension should do the job.
For example for testing that :
public String publish(Object domainObj) {
template.convertAndSend(topic.getTopic(), domainObj.toString());
return "Event Published";
}
I expect that topic and template be fields of the current class.
These fields could be set by constructor.
So you could write something that check that convertAndSend() is eventually executed with the correct parameters :
#Mock
RedisTemplate<String, Object> templateMock;
#Test
void publish(){
Topic topicFixture = new Topic(...);
Object domainObjFixture = new FooBar(...);
Publisher publisher = new Publisher(templateMock, topicFixture);
//when
publisher.publish(domainObjFixture);
// then
Mockito.verify(templateMock)
.convertAndSend(topicFixture.getTopic(), domainObjFixture);
}
But I don't think that the unit test of these two classes be enough because it never tests the final things : the JMS processing performed by Redis backend.
Particularly, the RedisConfig part that you set with specific things as serializers that have important side effects on the processing.
For my part, I try to always write integration or partial integration tests for Redis backend stuffs to ensure a good no regression harness.
The java embedded-redis library is good for that. It allows to start a redis server
on localhost (works on Windows as well as on Linux).
Starting and stopping the redis server is as simple as :
RedisServer redisServer = new RedisServer(6379);
redisServer.start();
// do some work
redisServer.stop();
Move the start() in the #BeforeEach and the stop() in the #AfterEach and the server is ready.
Then it still requires some adjustments to ensure that the redis configuration specified in Spring is well setup during the tests while using your local redis server and not the "real" redis server. Not always simple to set but great when it is done !
The simplest way to unit test this is to use embedded-redis module. What you do is in BeforeAll you can start embedded Redis and stop the embedded Redis in AfterAll method.
You can also PostConstruct PreDestroy annotations to accomplish this.
If you're looking for Junit5 then you can find the code in my repo here
See BootstrapRedis annotation and their usage here
https://github.com/sonus21/rqueue/blob/7ef545c15985ef91ba719f070f7cc80745525047/rqueue-core/src/test/java/com/github/sonus21/rqueue/core/RedisScriptFactoryTest.java#L40

Unable to Mock functions inside static method Powermock

I am writing unit test for the below code using junit and mockito
public class Abc implements Runnable
{
private static ServerSocket server;
private static int port;
public Abc(int cPort)
{
port = cPort;
}
public void run()
{
init();
}
public static void init()
{
try {
server = new ServerSocket(port);
...something...
client.close();
}
}
catch(IOException e)
{
System.out.println("Exception inside init()...");
e.printStackTrace();
}
}
};
Unit test I have written
#RunWith(PowerMockRunner.class)
#PrepareForTest({ServerSocket.class})
public class abcTest {
#Mock (name = "server") //same name as private var.
ServerSocket mockServer;
#InjectMocks
Abc abc;
#Test
public void testInit() throws Exception {
int port = 1880;
Socket mockClient = Mockito.mock(Socket.class);
PowerMockito.whenNew(ServerSocket.class).
withArguments(anyInt()).thenReturn(mockServer);
abc = new Abc(port);
Abc.init();
PowerMockito.verifyNew(ServerSocket.class).withArguments(port);
}
};
But the call always go to original function definition. I am using junit 4.11 with mockito 2.28.2 and powermockito 2.0.2. I'm using java after a long time. Now its feel like kind of new. Please correct me if anything wrong in the code also.
You will need to change your PrepareForTest annotation
to #PrepareForTest({Abc.class}).
From the PowerMockito docu:
This annotation tells PowerMock to prepare certain classes for testing. Classes needed to be defined using this annotation are typically those that needs to be byte-code manipulated
In this case that refers to the class which creates the new instance of ServerSocket. ServerSocket itself is a non-final public class that does not require special handling from PowerMockito (instead Mockito can deal with this class on its own).
You could also change your test to do the following:
#Test
public void testInit() throws Exception {
int port = 1880;
ServerSocket mockServer = Mockito.mock(ServerSocket.class);
PowerMockito.whenNew(ServerSocket.class)
.withArguments(Mockito.anyInt()).thenReturn(mockServer);
Abc.port = port;
Abc.init();
PowerMockito.verifyNew(ServerSocket.class).withArguments(port);
}
(This first point is unrelated to whether the test fails or succeeds)
I do not know why you mix object's and static method behaviour together, but I think you should change that.In the test instead of creatic an ABC object, just could just set the static port variable directly.
Or alternatively change the whole ABC class into an object.
#InjectMocks failed for me as there is no default constructor
(Actually I got an error message in the console when trying to execute your code)
Additonaly you create a new instance of ABC in your test, which would have overwritten the things done by the annotations. Also as server is created during the init call, there is no need to inject a mock for it.
powermockito 2.0.2 actually depends on junit 4.12, so I am not sure what effects downgrading to an older version might have.
Socket mockClient seemed somewhat unrelated to the code your posted, so I removed it from my example in the answer, however as you use a client (I assume that is your Socket) in your code your probably need to do some mocking for that as well and provide the mock to the method accordingly.

Is it possible to name a test suite in JUnit 4?

In JUnit3, one would could name a test suite like this:
public static Test suite() {
TestSuite suite = new TestSuite("Some test collection");
suite.addTestSuite(TestX.class);
return suite;
}
Is there an equivalent way to do this in JUnit4?
Thanks.
EDIT
Thank you, I actually managed to get it working. My question was if there is a JUnit4 equivalent way of specifying the name/description of a test suite, like in JUnit3 with "Some test collection".
Some background:
I'm converting junit tests in legacy code to the version 4, and I don't want to lose any information if possible. I apologize, I should really have been more specific in the original question.
You can do this with the Suite runner #RunWith(Suite.class):
#RunWith(Suite.class)
#SuiteClasses({Test1.class, Test2.class, TestX.class})
public class MySuite {}
Where Test1, Test2, TestX contain your tests
ref. RunWith, Suite
update:
WRT changing the actual description of your suite, I don't think there's a way to do it out-of-the-box (if there is I haven't seen it yet). What you can do, is to define your own runner with a custom description [update2]:
#RunWith(DescribedSuiteRunner.class)
#SuiteClasses({Test1.class, Test2.class, TestX.class})
#SuiteDescription("Some test collection")
public class MySuite {}
public class DescribedSuiteRunner extends Suite {
// forward to Suite
public DescribedSuiteRunner(Class<?> klass, RunnerBuilder builder)
throws InitializationError {
super(klass, builder);
}
#Override
protected String getName() {
return getTestClass()
.getJavaClass()
.getAnnotation(SuiteDescription.class)
.value();
}
}
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.TYPE)
public #interface SuiteDescription {
String value();
}
The default implementation of getName just returns the class being tested's name
Yes, In JUnit 3.x, the JUnit methods had to be specifically named. They needed to begin with the word test in order for JUnit to run that as a test case. Now you can just use the #Test annotation:
#Test
public void thisIsMyTest() {
// test goes here
}
Also in JUnit4 you can state if you want some tests to run before or after all the tests in this class are invoked:
#Before
public void init() throws Exception {
System.out.println("Initializing...");
}
#After
public void finish() throws Exception {
System.out.println("Finishing...");
}
Further comparisons between JUnit3 and JUnit4 here and here.
Edit: after blgt's comment, I see I might have misunderstood your intent.
You are probably looking for #RunWith(Suite.class) - When a class is annotated with #RunWith, JUnit will invoke the class in which is annotated so as to run the tests, instead of using the runner built into JUnit. Full example of usage is here, tl;dr below:
#RunWith(Suite.class)
#SuiteClasses({ FirstTest.class, SecondTest.class })
public class AllTests {
...
}

Error in Parameterised test cases in Junit

I am trying to write a parameterized test case in JUnit. My code looks like this:
#RunWith(Parameterized.class)
#PrepareForTest({AR9DirectDebitFileWriterCustomization.class})
public class AR9DirectDebitFileWriterCustomizationTest2 extends AR3BasicUnitTest {
private DirectDebitExtractDetRec mockObj;
private ARApplicationContext mockAppCon;
private AR9DirectDebitFileWriterCustomization spyObj = null;
AccountDBViewData mockdbData;
AccountDBView mockdbView;
SearchInvoicesDBViewData[] mocksearchInvdbviewdatarr = new SearchInvoicesDBViewData[1];
#Before
public void setUp() throws Exception {
AR9DirectDebitFileWriterCustomization ar9Obj = new AR9DirectDebitFileWriterCustomization(mockdbView, mocksearchInvdbviewdatarr, mockdbData);
spyObj = PowerMockito.spy(ar9Obj);
}
public AR9DirectDebitFileWriterCustomizationTest2(DirectDebitExtractDetRec mockObj_from_collection, ARApplicationContext mockAppCon_from_collection) {
this.mockObj = mockObj_from_collection;
this.mockAppCon = mockAppCon_from_collection;
}
#Parameterized.Parameters
public static Collection<Object[]> getparameters() throws ACMException{
return Arrays.asList(new Object[][]{
{mock(DirectDebitExtractDetRec.class),mock(ARApplicationContext.class)}
});
}
#Test
#Parameters
public final void testAddFileRecordCustObjectARApplicationContext( ) throws Exception {
.....SOME CODE
}
Whenever I right click on the testAddFileRecordCustObjectARApplicationContext function and run it as Junit test I get an initialization error :
java.lang.Exception: No tests found matching Method
testAddFileRecordCustObjectARApplicationContext(amdocs.ar.customizationexits.handlers.helpers.AR9DirectDebitFileWriterCustomizationTest2)
from org.junit.internal.requests.ClassRequest#3fa50b at
org.junit.internal.requests.FilterRequest.getRunner(FilterRequest.java:37)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.(JUnit4TestReference.java:33)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestMethodReference.(JUnit4TestMethodReference.java:25)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:54)
at
org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:38)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:452)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at
org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
After looking for several hours on internet about this issue I could not find anything meaningful. In this scenario I am using spy and powerMocktio Functionality as well.I am not sure what is the root of this error .
And interesting thing is when I run it without using Parameterised test ,it works perfectly fine.
I had very similar error:
No tests found matching data with any parameter from...
According to my observations, it is caused by another strange error:
Unable to mock class ... due to a missing dependency
Only the first I see when I run the test, and the second, when I debug it. According to https://stackoverflow.com/a/23788935/715269,
https://stackoverflow.com/a/25659518/715269, it is the bug connected to classpath reading. The problem disappears, when we upgrade JMockit to higher versions.

Accessing non public Method of Object in JUNIT

Hi I am new to unit testing. Is it possible to access methods that are private?
A very simple example
ObjectA
----------
File file;
private void setupFile (){
//do something
file = "C:\file.dat"
}
In TestCase
File sth = ObjectA.setupFile();
assertNotNull(sth);
I am unable to test whether the file variable is null in method ObjectA.setup()
as I cannot run ObjectA.setupFile()
I am not sure about whether doing like this make sense in terms of unit testing.
So is that a better practice to write every method returning sth and set them public for easier unit testing?
Thanks in advance
In general, you should avoid changing the access of a method/field to enable testing. If you do this then you risk developers using the method directly.
However, if you do need to, then making it protected as Deco says is a good way, so it's accessible from the JUnit tests. If you do this, make sure that it is well documented that this is an method for internal use.
A better way is to test the behaviour of the public methods; you shouldn't care about internal implementation details of a class, so you should only be testing public methods. It's hard to tell from your code, but presumably, the setupFile() has effects later on other methods, so you can test those effects, not the fact that file is not null.
External dependencies (such as dependencies on file system, environment variables) can be worked around in your tests, or injected directly into the class. For the general principle, see my answer to How to test code dependent on environment variables using JUnit?
If it is not absolutely necessary to have the method as private, you can have it as package private (i.e. default access) so that you can call it directly in a JUnit test.
Package private methods can only be used in the package that they are declared, and do not become part of the API of the class. You declare a method package private by putting no modifier on it's declaration.
Here's an example to demonstrate:
public class MyClass() {
int foo;
public MyClass() {
this.foo = 0;
}
void notSoComplexCalculationMethod(int a) {
foo = a * 2;
}
//Other methods here . . .
}
public class MyClassTest extends TestCase {
private MyClass myClass;
protected void setUp() {
super.setUp();
myClass = new MyClass();
}
public void testNotSoComplexCalculationMethod() {
int a = 2;
assertEquals(4, myClass.notSoComplexCalculationMethod(a));
//Unit test passes, yay! Now you've tested a package private method.
}
}