Consider:
package de.test; public class MyService { int invocations = 0; public void doSomething(int x){ invocations++; if (invocations==5){ throw new RuntimeException("exception"); } return; }; } package de.test; public class MyProcessor { private MyService myService; public MyProcessor(MyService myService) { this.myService = myService; } public void process(int n) { myService.doSomething(n); System.out.println("Processed: " + n); } }
And this Testcode:
package de.test; import de.bodo.MyProcessor; import de.bodo.MyService; import org.junit.jupiter.api.Test; import org.mockito.Mockito; public class ProcessorTest { @Test public void processTest() { MyService myService = Mockito.spy(new MyService()); MyProcessor myProcessor = new MyProcessor(myService); myProcessor.process(0); myProcessor.process(1); myProcessor.process(2); myProcessor.process(2); RuntimeException thrown = assertThrows( RuntimeException.class, ()-> myProcessor.process(2), " expected exception" ); myProcessor.process(2); Mockito.verify(myService, Mockito.atMostOnce()).doSomething(0); Mockito.verify(myService, Mockito.atMostOnce()).doSomething(1); Mockito.verify(myService, Mockito.atMost(4)).doSomething(2); Mockito.verify(myService, Mockito.atLeastOnce()).doSomething(1); Mockito.verify(myService, Mockito.atLeast(2)).doSomething(2); Mockito.verify(myService, Mockito.times(4)).doSomething(2); Mockito.verify(myService, Mockito.never()).doSomething(3); } }
So you can not only check how often a method was called, but even you can count how often a method was call with one specific argument (the integer number in this example.)
You need to add Mockito to your pom.xml:
!-- https://mvnrepository.com/artifact/org.mockito/mockito-junit-jupiter --> <dependency> <groupId>org.mockito</groupId> <artifactId>mockito-junit-jupiter</artifactId> <version>4.8.1</version> <scope>test</scope> </dependency> <!-- https://mvnrepository.com/artifact/org.mockito/mockito-core --> <dependency> <groupId>org.mockito</groupId> <artifactId>mockito-core</artifactId> <version>4.8.1</version> <scope>test</scope> </dependency>
Source: https://www.logicbig.com/tutorials/unit-testing/mockito/verifying-varing-number-of-invocations.html
