如何模拟 dynamodbmapper 扫描

Question

我有以下要模拟的代码：

public void getOrders(Response response){
    logger.log("Getting all orders");

    DynamoDBScanExpression scanExpression = new DynamoDBScanExpression()
            .withProjectionExpression("OrderId");

    PaginatedScanList<Orders> orders = dynamoDBMapper.scan(Orders.class, scanExpression);

    response.setData(orders..stream()
            .collect(Collectors.toList()));
}

我试图模拟的方式是：

Mockito.when(mockDynamoDBMapper.scan(Orders.class, 
             Mockito.any())).thenReturn(mockPaginatedList);

我得到以下异常：

如果匹配器与原始值组合，则可能会发生此异常： //不正确： someMethod(anyObject(), "原始字符串");使用匹配器时，所有参数都必须由匹配器提供。例如： //正确的： someMethod(anyObject(), eq("匹配器的字符串")); 有关更多信息，请参阅 Matchers 类的 javadoc。

我应该如何用任何DynamoDBScanExpression 对象模拟dbmapper.scan 方法？

Answer 1

该错误对您的问题有明确的答案。你想要的是：

Mockito.when(mockDynamoDBMapper.scan(eq(Orders.class), 
             Mockito.any())).thenReturn(mockPaginatedList);

必须为匹配器提供匹配器 - eq(Orders.class)，而不是原始值 - Orders.class

Answer 2

一般来说，我首先要模拟 PaginatedScanList，这是 mapper.scan () 给我们的响应类型，然后我将该响应模拟分配给它在扫描 () 时创建的映射器模拟被称为

    // here I define the values ​​that will be assigned to the filter
    Map <String, AttributeValue> expressionAttributeValues ​​= new HashMap <> ();
    expressionAttributeValues.put (": attributeValue", new AttributeValue (). withS ("value"));
    // the definition of the epxpression for the scan
    DynamoDBScanExpression scanExpression = new DynamoDBScanExpression ();
    scanExpression.setLimit (1); // amount of data to return
    scanExpression.setFilterExpression (("email =: attributeValue")); // the attribute to filter by
    scanExpression.setProjectionExpression ("id"); // the data to return from the row or json
    scanExpression.setExpressionAttributeValues ​​(expressionAttributeValues); // place the value by which to filter

    DynamoDBMapper mapper = mock (DynamoDBMapper.class); // The mock was created for the mapper, which is the one with different methods such as query, scan, etc.
    PaginatedScanList scanResultPage = mock (PaginatedScanList.class); // definition of the mock for the scan result

    when (scanResultPage.size ()). then (invocation -> 3); // what to return when the PaginatedScanList is called

    when (mapper.scan (Person.class, scanExpression)). then (invocation -> scanResultPage); // here returns our mocked PaginatedScanList for the scan function