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How to mock a static method in side a public class using Power mockito?

Hi every one I am trying to mock a static method name mapCreditInfo(UCIPin, creditAssessmentResults) which has two parameters UCIPin and creditAssessmentResults. UCIPin is String type and creditAssessmentResults is List
This method is inside a public class ResponseMapper
type as shown below:
private CreditInfo getAccountByUCI(String audiUser, String UCIPin) throws EnterpriseCustomerVerificationException {
List<CreditAssessmentResult> creditAssessmentResults = creditInfoRepository.getUCISummary(UCIPin, audiUser);
return ResponseMapper.mapCreditInfo(UCIPin, creditAssessmentResults);
}
Note: getAccountbyUCI method is called inside another public method
name executeCustomerVerification which is in the class
EnterpriseCustomerVerificationService
ResponseMapper class
public class ResponseMapper {
public static CreditInfo mapCreditInfo(String UCIPin, List<CreditAssessmentResult> creditAssessmentResults) {
CreditInfo creditInfo = new CreditInfo();
creditInfo.setUCIPin(UCIPin);
List<AccountCreditInfo> accountCreditInfos = new ArrayList<AccountCreditInfo>();
for (CreditAssessmentResult creditAssessmentResult : creditAssessmentResults) {
AccountCreditInfo accountCreditInfo = new AccountCreditInfo();
accountCreditInfo.setDelinquenctBalance(creditAssessmentResult.getPastDueAmount());
accountCreditInfo.setNonPayDisconnect(creditAssessmentResult.getNonpayDiscount());
accountCreditInfo.setPreviousAccountNumber(creditAssessmentResult.getAccountNumber());
accountCreditInfo.setUnreturnedEquipmentFlag(creditAssessmentResult.getUnreturnedEquipment());
accountCreditInfos.add(accountCreditInfo);
}
creditInfo.setAccountCreditInfo(accountCreditInfos);
return creditInfo;
}
}
I have Tried like some portion of my test class as shown below :
Test Class
#PrepareForTest( EnterpriseCustomerVerificationService.class)
#RunWith(PowerMockRunner.class)
public class EnterpriseCustomerVerificationServiceTest {
#InjectMocks
private EnterpriseCustomerVerificationService enterpriseCustormerVerificationServiceMock ;
#Test
public void executeCustomerVerificationTest() throws Exception {
List<ErrorResponse> errorResponses = getErrorResponse();
List<String> mso = new ArrayList<String>();
mso.add("a");
mso.add("b");
mso.add("c");
AddressResponse addressResponse = getAddressResponse();
String experianAuthorization = "experianAuthorization";
String UCIPin = "110019";
String auditUser = "ABC";
CreditInfo credit = getCreditInfo();
CreditCheck creditCheck = getcreditCheck();
EnterpriseCustomerVerificationService spy = PowerMockito.spy(new EnterpriseCustomerVerificationService());
PowerMockito.when(spy,PowerMockito.method(EnterpriseCustomerVerificationService.class,"executeCreditCheck",CreditCheck.class)).withArguments(Mockito.any()).thenReturn("#1");
Mockito.when(creditInfoRepository.getUCISummary("110019", "test")).thenReturn(getCreditAssessmentResultList());
PowerMockito.mockStatic(ResponseMapper.class);
Mockito.when(ResponseMapper.mapCreditInfo(UCIPin, getCreditAssessmentResultList())).thenReturn(credit);
CustomerVerification cv = spy
.executeCustomerVerification(getCustomerVerificationRequest1(),
"101");
}
My question is how to mock static mapCreditInfo method using power Mockito ?
Thanks

Like this ...
#RunWith(PowerMockRunner.class)
#PrepareForTest({ResponseMapper.class})
public class ATest {
#Test
public void testMockingStatic() {
PowerMockito.mockStatic(ResponseMapper.class);
// if you want to use specific argument matchers
Mockito.when(ResponseMapper.mapCreditInfo(
uciPin, creditAssessmentResults)
).thenReturn(creditInfo);
// or if you want to match on any arguments passed into your static method ...
Mockito.when(ResponseMapper.mapCreditInfo(
ArgumentMatchers.anyString(),
ArgumentMatchers.anyList())
).thenReturn(creditInfo);
// ...
}
}
Notes:
#PrepareForTest prepares the class with the static methods which you want to mock
PowerMockito.mockStatic mocks all static methods that class
You can use standard Mockito when/then constructs to tell the mocked static methods what to return
The example above uses these dependencies:
org.mockito:mockito-core:2.7.19
org.powermock:powermock-module-junit4:1.7.0
org.powermock:powermock-api-mockito2:1.7.0
Update 1: based on your updated question which shows your test method ...
My example includes: #PrepareForTest({ResponseMapper.class}) your test method is not preparing ResponseMapper instead it is preparing EnterpriseCustomerVerificationService. It's like you are preparing the class which calls the class which has a static method rather than preparing the class which contains the static method.
I would strongly suggest creating a new test case - just temporarily - which looks like the one I have provided and use that to show yourself how to mock a static method and once you are comfortable with that then work that into your EnterpriseCustomerVerificationServiceTest.

Is it possible to change the source code? if so maybe you could try to solve the problem without using any mocking framework at all.
see my comment on How To Java Unit Test a Complex Class

Verify private static method on final class gets called using PowerMockito

I have the following class
public final class Foo {
private Foo() {}
public static void bar() {
if(baz("a", "b", new Object())) { }
}
private static boolean baz(Object... args) {
return true; // slightly abbreviated logic
}
}
And this is my Test:
#PrepareOnlyThisForTest(Foo.class)
#RunWith(PowerMockRunner.class)
public class FooTest {
#Test
public void bar() {
PowerMockito.mockStatic(Foo.class); // prepare
Foo.bar(); // execute
verifyPrivate(Foo.class, times(1)).invoke("baz", anyVararg()); // verify - fails
}
}
For that, I get the following error message - and I don't understand why...
Wanted but not invoked com.example.Foo.baz(
null );
However, there were other interactions with this mock.
Removing the prepare line above seems to make the verify line pass no matter for how many times you check for... :(
(Our SONAR code checks enforce that each test has some sort of assertXyz() in it (hence the call to verify()) and enforces a very high test coverage.)
Any ideas how to do this?

The problem with your code is that you mock Foo so your method implementations won't be called by default such that when you call Foo.call() it does nothing by default which means that it never avtually calls baz that is why you get this behavior. If you want to partially mock Foo, mock it using the option Mockito.CALLS_REAL_METHODS in order to make it call the real methods as you seem to expect, so the code should be:
#PrepareOnlyThisForTest(Foo.class)
#RunWith(PowerMockRunner.class)
public class FooTest {
#Test
public void bar() throws Exception {
PowerMockito.mockStatic(Foo.class, Mockito.CALLS_REAL_METHODS); // prepare
...
}
}

How do you mock a method in GroovyTestCase?

I've been trying to figure out stubbing and mocking through the groovy testing tutorial to no avail. I'm trying to stub (or mock, I'm not quite sure on the terminology) this method, however I can't figure out how to actually get the syntax right. I would appreciate some help. I'm using groovy 2.4.5
public class foo {
public static void main(String[] args){
method1();
}
public static void method1(){
//do stuff
Object baz = new Object();
method2(baz);
}
public static void method2(Object baz){
//do stuff
}
}
class FooTest extends groovy.util.GroovyTestCase {
void testMainLoop(){
def stubMethod2 = new StubFor(foo);
stubMethod2.ignore.method2
stubMethod2.use {
foo.method1();
}
}
}
This code throws the error:
groovy.lang.MissingPropertyException: No such property: method2 for class: groovy.mock.interceptor.Ignore
at org.codehaus.groovy.runtime.ScriptBytecodeAdapter.unwrap(ScriptBytecodeAdapter.java:53)
at org.codehaus.groovy.runtime.callsite.GetEffectivePogoPropertySite.getProperty(GetEffectivePogoPropertySite.java:87)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callGetProperty(AbstractCallSite.java:296)
at fooTest.testMainLoop(fooTest.groovy:14)

You should rather use:
stubMethod2.ignore('method2')
than:
stubMethod2.ignore.method2
Could you please clarify what you want to achieve?
BTW: I suggest to use spock instead of groovy built-in testing.

JUnit - test that a method has been called

I'm new to unit testing, and I'm trying to test that a method has been called. The method in question doesn't return anything.
public void example (boolean foo) {
if (foo) {
processFoo(foo);
}
else if (foo==false) {
processSomethingElse(foo);
}
}
I want to be able to test that the processFoo method is being called, but I don't know how to do that.
If mocking is required, then I have to use JMockit. Thanks!

Sorry I'm a little late to the party, but I have a couple of ideas for you.
First, you mention that one option is to use JMockit--that's great as it gives you a lot of flexibility. If you use JMockit, then the visibility of your processFoo() method doesn't much matter. Let's see what that might look like:
public class Subject {
public void example (boolean foo) {
if (foo) {
processFoo(foo);
}
else if (foo==false) {
processSomethingElse(foo);
}
}
private void processFoo(boolean b) {
System.out.println("b = " + b);
}
private void processSomethingElse(boolean bb) {
System.out.println("bb = " + bb);
}
}
So, one caveat with this option, though is that I'm going to assume processFoo() is a method on your test subject and I'm going to use a partial mock to change the test subject--not something I really like to do, but this is an example. In general, it is best to only mock the dependencies of your test subject rather than behavior of the test subject itself--you have been advised! Note that the processFoo() method of the test subject is private. I'm going to substitute a method for the test with JMockit's partial mocking and the visibility of that new method does not have to match the original.
import static org.assertj.core.api.Assertions.assertThat;
import mockit.Mock;
import mockit.MockUp;
import mockit.integration.junit4.JMockit;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
#RunWith(JMockit.class)
public class SubjectTest {
private Subject testSubject = new Subject();
private boolean processFooCalled = false;
#Before
public void setup() {
new MockUp<Subject>() {
#Mock
public void processFoo(boolean b) {
processFooCalled = true;
};
};
}
#Test
public void should_call_processFoo() {
testSubject.example(true);
assertThat(processFooCalled).isTrue();
}
#Test
public void should_not_call_processFoo() {
testSubject.example(false);
assertThat(processFooCalled).isFalse();
}
}
Ok, so that was the first option. It's actually a little easier if you forget JMockit for this one, assuming you are able to subclass your test subject and override the processFoo() method:
public class Subject {
public void example (boolean foo) {
if (foo) {
processFoo(foo);
}
else if (foo==false) {
processSomethingElse(foo);
}
}
protected void processFoo(boolean b) { // NOTE: protected access here!
System.out.println("b = " + b);
}
private void processSomethingElse(boolean bb) {
System.out.println("bb = " + bb);
}
}
So, in this case, the strategy is simply to subclass your test subject and replace the implementation of the method you wish to observe being called. It might look like this:
import static org.assertj.core.api.Assertions.assertThat;
import org.junit.Test;
public class SubjectTest2 {
private Subject testSubject = new TestableSubject();
private boolean processFooCalled = false;
#Test
public void should_call_processFoo() {
testSubject.example(true);
assertThat(processFooCalled).isTrue();
}
#Test
public void should_not_call_processFoo() {
testSubject.example(false);
assertThat(processFooCalled).isFalse();
}
class TestableSubject extends Subject {
#Override
protected void processFoo(boolean b) {
processFooCalled = true;
}
}
}
Give it a whirl. Hope it helps!

You could use a counter variable in your class and increment it whenever the method is called, or use a print statement. If you don't have access to the processFoo method, a simple approach would be to do this at the time that processFoo is called in another method, if that's the only place where it can possibly be called.
For example:
public static int processFooCalls = 0;
// ...
public void example (boolean foo) {
if (foo) {
processFoo(foo);
processFooCalls += 1;
// and/or
System.out.println("processFoo method was called");
}
// ...
}
public static void main (String[] args) {
// main routine here...
System.out.println("'processFoo' was called " + processFooCalls + " times.");
}
If processFoo can be called elsewhere, and you need to consider this possibility as well, then you'll need to have access to the processFoo code in order to do this, e.g.:
void processFoo( boolean b ) {
// increment number of times processFoo was called here, and/or print, as follows
processFooCalls += 1;
System.out.println("called processFoo method!");
/* some functionality */
}

Looking at the JMockit documentation, you will need the following tools:
Static Mocking: http://jmockit.github.io/tutorial/BehaviorBasedTesting.html#staticPartial
Invocation Counts: http://jmockit.github.io/tutorial/BehaviorBasedTesting.html#constraints
Combining the two in a test (my syntax may be a little off since I'm more accustomed to Mockito, but the concept should hold):
#Test
public void someTestMethod(#Mocked({"processFoo"}) final ExampleClass exampleclass)
{
new Expectations() {{
exampleclass.processFoo(); times = 1;
}};
exampleclass.example(true);
}
This should mock the processFoo method, leaving everything else intact, and checks to make sure it is called exactly once.

Don't consider doing any kind of partial mocking for this, all you're doing in that case is ensuring that if you want to refactor your code your tests will fail. There is a mantra in unit testing - "never test private methods".
What you should be doing is testing that the method you call conforms to the behaviour you want to see. In this case what happens when foo is true is what's important, not that it calls processFoo. So if foo is true you want to be testing that the action processFoo carries out is true and nothing else.

Mock a constructor with parameter

I have a class as below:
public class A {
public A(String test) {
bla bla bla
}
public String check() {
bla bla bla
}
}
The logic in the constructor A(String test) and check() are the things I am trying to mock. I want any calls like: new A($$$any string$$$).check() returns a dummy string "test".
I tried:
A a = mock(A.class);
when(a.check()).thenReturn("test");
String test = a.check(); // to this point, everything works. test shows as "tests"
whenNew(A.class).withArguments(Matchers.anyString()).thenReturn(rk);
// also tried:
//whenNew(A.class).withParameterTypes(String.class).withArguments(Matchers.anyString()).thenReturn(rk);
new A("random string").check(); // this doesn't work
But it doesn't seem to be working. new A($$$any string$$$).check() is still going through the constructor logic instead of fetch the mocked object of A.

The code you posted works for me with the latest version of Mockito and Powermockito. Maybe you haven't prepared A?
Try this:
A.java
public class A {
private final String test;
public A(String test) {
this.test = test;
}
public String check() {
return "checked " + this.test;
}
}
MockA.java
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.equalTo;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.powermock.api.mockito.PowerMockito;
import org.powermock.core.classloader.annotations.PrepareForTest;
import org.powermock.modules.junit4.PowerMockRunner;
#RunWith(PowerMockRunner.class)
#PrepareForTest(A.class)
public class MockA {
#Test
public void test_not_mocked() throws Throwable {
assertThat(new A("random string").check(), equalTo("checked random string"));
}
#Test
public void test_mocked() throws Throwable {
A a = mock(A.class);
when(a.check()).thenReturn("test");
PowerMockito.whenNew(A.class).withArguments(Mockito.anyString()).thenReturn(a);
assertThat(new A("random string").check(), equalTo("test"));
}
}
Both tests should pass with mockito 1.9.0, powermockito 1.4.12 and junit 4.8.2

To my knowledge, you can't mock constructors with mockito, only methods. But according to the wiki on the Mockito google code page there is a way to mock the constructor behavior by creating a method in your class which return a new instance of that class. then you can mock out that method. Below is an excerpt directly from the Mockito wiki:
Pattern 1 - using one-line methods for object creation
To use pattern 1 (testing a class called MyClass), you would replace a call like
Foo foo = new Foo( a, b, c );
with
Foo foo = makeFoo( a, b, c );
and write a one-line method
Foo makeFoo( A a, B b, C c ) {
return new Foo( a, b, c );
}
It's important that you don't include any logic in the method; just the one line that creates the
object. The reason for this is that the method itself is never going
to be unit tested.
When you come to test the class, the object that you test will
actually be a Mockito spy, with this method overridden, to return a
mock. What you're testing is therefore not the class itself, but a
very slightly modified version of it.
Your test class might contain members like
#Mock private Foo mockFoo;
private MyClass toTest = spy(new MyClass());
Lastly, inside your test method you mock out the call to
makeFoo with a line like
doReturn( mockFoo )
.when( toTest )
.makeFoo( any( A.class ), any( B.class ), any( C.class ));
You can use matchers that are more specific than any() if you want to
check the arguments that are passed to the constructor.
If you're just wanting to return a mocked object of your class I think this should work for you. In any case you can read more about mocking object creation here:
http://code.google.com/p/mockito/wiki/MockingObjectCreation

With Mockito you can use withSettings(). For example if the CounterService required 2 dependencies, you can pass them as a mock:
UserService userService = Mockito.mock(UserService.class);
SearchService searchService = Mockito.mock(SearchService.class);
CounterService counterService = Mockito.mock(CounterService.class, withSettings().useConstructor(userService, searchService));

Starting with version 3.5.0 of Mockito and using the InlineMockMaker, you can now mock object constructions:
try (MockedConstruction mocked = mockConstruction(A.class)) {
A a = new A();
when(a.check()).thenReturn("bar");
}
Inside the try-with-resources construct all object constructions are returning a mock.

Without Using Powermock .... See the example below based on Ben Glasser answer since it took me some time to figure it out ..hope that saves some times ...
Original Class :
public class AClazz {
public void updateObject(CClazz cClazzObj) {
log.debug("Bundler set.");
cClazzObj.setBundler(new BClazz(cClazzObj, 10));
}
}
Modified Class :
#Slf4j
public class AClazz {
public void updateObject(CClazz cClazzObj) {
log.debug("Bundler set.");
cClazzObj.setBundler(getBObject(cClazzObj, 10));
}
protected BClazz getBObject(CClazz cClazzObj, int i) {
return new BClazz(cClazzObj, 10);
}
}
Test Class
public class AClazzTest {
#InjectMocks
#Spy
private AClazz aClazzObj;
#Mock
private CClazz cClazzObj;
#Mock
private BClazz bClassObj;
#Before
public void setUp() throws Exception {
Mockito.doReturn(bClassObj)
.when(aClazzObj)
.getBObject(Mockito.eq(cClazzObj), Mockito.anyInt());
}
#Test
public void testConfigStrategy() {
aClazzObj.updateObject(cClazzObj);
Mockito.verify(cClazzObj, Mockito.times(1)).setBundler(bClassObj);
}
}

Mockito has limitations testing final, static, and private methods.
Alternate Solution:
with jMockit testing library, you can do few stuff very easy and straight-forward as below:
Mock constructor of a java.io.File class:
new MockUp<File>(){
#Mock
public void $init(String pathname){
System.out.println(pathname);
// or do whatever you want
}
};
the public constructor name should be replaced with $init
arguments and exceptions thrown remains same
return type should be defined as void
Mock a static method:
remove static from the method mock signature
method signature remains same otherwise

Using Mockito 4 (but I suspect this is true for Mockito from 3.5.0 version) you can mock the constructor and, in the initializer, you can assert the values of the parameters.
For example:
try (MockedConstruction<A> constr = mockConstruction(A.class,
(mock, context) -> {
if (context.getCount() == 1) {
assertArrayEquals(context.arguments().toArray(), new Object[] {"test"});
} else {
fail("No more calls should happen");
}
})) {
// Do the rest of assertions.
}
Notice that you need to put the MockedConstruction instantiation in a try-with-resources otherwise the mocked construction is leaked outside the test.