使用Mockito模拟自定义对象

Question

我正在使用Mockito来模拟一些自定义对象，但我认为它没有做我想做的事情。它抛出了NPE。我想知道这是否是模拟对象的正确方法。

正在测试的代码

ITransformer transformer = new SendDocumentsRESTTransformer();
ITransformerResult result = transformer.transformRequest(args);

JUnit测试用例

private ITransformer transformer;

@Before
public void setUP(){
  transformer = mock(ITransformer.class);
}

@Test
public void testSendDocuments() throws Exception {
    AppContext.setApplicationContext( applicationContext );

    DocusignRESTProvider docusignRestProvider = new DocusignRESTProvider();
    docusignRestProvider.setLoggingHandler( iloggingHandler );
    docusignRestProvider.setDocumentManager( iDocumentManager );
    docusignRestProvider.setConfiguration( iProviderConfiguration );

    iClientUserDto.setActive( Boolean.TRUE );
    iClientUserDto.setUserName( "GW_SYS_USER" );
    iClientUserDto.setPassword( "GWPASSWORD" );

    when( args.getClientUserDto()).thenReturn( iClientUserDto );
    when( transformer.transformRequest(args)).thenReturn( transformerResult );

    docusignRestProvider.sendDocuments( iClientUserDto, iDocumentSet );