如何验证 class 类型的模拟方法参数包含使用 mockito 的值 junit

Question

I have a service unit test, where I need to mock a Dao but also i need to verify the method parameter of class type property studyRefActive contains a value "Y"

RegDao class:

public class RegDao {
----
----
public void save(Study study){
  //DB call to insert 
}

}

RegService class:

public class RegService {

private RegDao  regDao;
 //Inject dao here 

  public void saveStudy(Study study){
    
     //some data assignements
    study.setStudyRefActive("Y");
    regDao.save(study);

   }


}

my unit test:

RegDao mockRegDao = mock(RegDao.class);
RegService regService = new RegService(mockRegDao);
Study study = new Study();
Mockito.doNothing.when(mockRegDao).saveStudy(any(Study.class));
 regService.saveData(study)

so my question is how can i validate the Study DTO has the value 'Y' for the property studyRefActive?

Help Appreciated!

Answer 1

You can use an ArgumentCaptor. Let me elaborate below:

RegDao mockRegDao = mock(RegDao.class);
RegService regService = new RegService(mockRegDao);
Study study = new Study();
//I think you can remove the line below. Please test it on your implementation.
Mockito.doNothing.when(mockRegDao).saveStudy(any(Study.class)); 

regService.saveData(study);

ArgumentCaptor<Study> studyArgumentCaptor = ArgumentCaptor.forClass(Study.class);
Mockito.verify(mockRegDao).save(studyArgumentCaptor.capture());

//here you are going to retrieve the value that was sent as a parameter to the method "save" of RegDao class.
Study savedStudy = studyArgumentCaptor.getValue();