Spring MVC 5 ResultMatcher jsonPath null value

Question

After upgrading my rest service from Spring Boot 1.5.10 to 2.0.0 I encountered my tests failing which passed before.

Following Scenario:

import org.mockito.internal.matchers.Null;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;

...

.andExpect(jsonPath("img").value(Null.NULL))

Fails now in Spring MVC 5 with following message:

java.lang.AssertionError: JSON path "img"
Expected :isNull() Actual :null

What is the correct way in Spring MVC 5 to assert that the value of the jsonPath is null?

Are you using jayway lib for jsonpath? Can you please show the name package name for jsonpath ? — notionquest, Mar 14 '18 at 14:12
I am using `org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;` — mrkernelpanic, Mar 14 '18 at 14:16
alternate way is to use new JsonPathExpectationsHelper("$.img").assertValueIsEmpty(jsonContent); — notionquest, Mar 14 '18 at 14:52

score 25 · Accepted Answer · answered Mar 14 '18 at 14:46

25

Answering my own question as I found the solution by myself.

You have to use the correct Matcher, in my case org.hamcrest.core.IsNull

So I had to change to

import org.hamcrest.core.IsNull;
...
andExpect(jsonPath("img").value(IsNull.nullValue()))

answered Mar 14 '18 at 14:46

mrkernelpanic

4,268
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4javier · Answer 2 · 2022-04-25T11:01:47.987

4

April 2022, Hamcrest 2.2

nullValue() is a standalone static method importable by org.hamcrest.CoreMatchers.nullValue.

So, updated solution resolves to

static import org.hamcrest.core.nullValue;
...
andExpect(jsonPath("img").value(nullValue()))

edited Apr 25 '22 at 11:01

answered Apr 25 '22 at 10:40

4javier

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score 1 · Answer 3 · answered May 19 '18 at 21:04

1

You can use content().srtring(Matcher matcher) and then use IsEmptyString matcher

result.andDo(print())
      .andExpect(status().isNoContent())
      .andExpect(content().string(IsEmptyString.isEmptyOrNullString()));

answered May 19 '18 at 21:04

barrenaedu

19
2

It's not the same. Your solution will verify that response doesn't have **any content at all**, but the required solution, which was provided by @mrkernelpanic himself, should verify that **only one field** from the response Json object is NULL. It's two definitely different checks. – provisota Mar 31 '22 at 10:23
`isEmptyOrNullString()` was deprecated you should use `emptyOrNullString()` – Falcon May 09 '23 at 07:37

Spring MVC 5 ResultMatcher jsonPath null value

3 Answers3

April 2022, Hamcrest 2.2