JUnit using mockito

Question

我有一个名为service .class的服务类和两个名为a .class和B.class的类服务类有一个方法，该方法调用基于类a的对象的方法;B.那么我如何创建模拟对象的A &这样我就可以在服务类方法中传递那个mock对象。这是JUnit测试所需要的。如。Service.class

    class Service {
            A a;
            Response response;
            public Service(){
            }
            public Service(A a, B b){
                this.a= a;
                this.b = b;
            } 
            public Respose test(InputStream i,InputStream i1){
                InputStream inStreamA = a.method1(i,i1);
                Response response=  response.method2(inStreamA);
                return response;
            }

and in Response.class
   public Response method2(InputStream i1)){
     return Response.ok().build();
}

编辑:我的JUnit课我已经创建了两个类

     A mockedA = mock(A.class);
        Response mockedResponse = mock(Response.class);
         when(mockedA.method1(new ByteArrayInputStream("test").getByte()).thenReturn(InputStream);
         when(mockedResponse.method2(new ByteArrayInputStream("test").getByte()).thenReturn(Res);
        Service service = new Service(mockedA , mockedResponse );
        Response i = service.test(new ByteArrayInputStream("test").getByte(), new ByteArrayInputStream("test1").getByte());
       System.out.print(response);  
       assertEquals(200,response.getStatus()); 
// but here i am getting null pointer

Answer 1

您可以在测试中简单地模拟它们。

首先添加以下导入:import static org.mockito.Mockito.*;

然后在你的代码

 //You can mock concrete classes, not only interfaces
 A mockedA = mock(A.class);
 B mockedB = mock(A.class);
 //stubbing
 when(mockedA.method1(any(InputStream.class))).thenReturn(null);
 when(mockedB.method2(any(InputStream.class))).thenReturn(null);

然后将它们作为参数传递给Service构造函数。

如果没有存根，你模拟的类方法将返回空值，通过存根你可以指定它们应该返回什么值。

下面的代码显示测试方法返回400

  A mockedA = mock(A.class);
  B mockedB = mock(B.class);
  when(mockedA.method1(new ByteArrayInputStream("test".getBytes()))).thenReturn(null);
  when(mockedB.method2(new ByteArrayInputStream("test".getBytes()))).thenReturn(null);
  Service service = new Service(mockedA , mockedB );
  String i = service.test(new ByteArrayInputStream("test".getBytes()));
  System.out.println(i);