java - 使用 Junit 和 mockito 测试 catch block 逻辑

Question

我有类要测试，如下所示:

public class ReportWriter {
    private FileWrter fw; 
    private static Logger logger = Logger.getLogger(ReportWriter.class); 
    public ReportWriter(FileWrter fw) {
        this.fw = fw;
    } 
    public void writeData(Data) {
        try{
            fw.open();
            fw.write(data);
            fw.close();
        } **catch(DiskFullException e) {
            //after catch we log and handle it without rethrow the exception
            logger.log(Level.WARN, "warning log here", e);
            // some more logic here
            sendEmailToSupport();
        }**
    } 
}

问题是如何测试catch block 中的逻辑？

Answer 1

如果 sendEmailToSupport 至少是一个包级别的方法，那么您可以采用如下方法:

public class ReportWriterClass{

   @Spy
   @InjectMocks
   private ReportWriter reportWriterSpy;

   @Mock
   private FileWrter fwMock;

   @Before
   public void init(){
       MockitoAnnotations.initMocks(this);
   }

   @Test
   public void shouldSendEmail_whenDiskIsFull() throws Exception{
       // Arrange
       Data data = new Data();

       doNothing().when(reportWriterSpy).sendEmailToSupport());
       doThrow(new DiskFullException()).when(fwMock).write(data);

       // Act
       reportWriterSpy.writeData(data);

      // Assert
      verify(reportWriterSpy).sendEmailToSupport();
   }
}