当结果Object/json包含Long字段类型时，对Spring MVC REST控制器进行单元测试

Question

我在尝试使用MockMvcResultMatchers测试Spring REST服务的JSON输出时遇到了一个问题，返回的对象应该包含一个Long值。

只有当JSON对象中的值高于Integer.MAX_value时，测试才会通过。这对我来说有点奇怪，因为我觉得我应该能够测试所有适用的值。

我知道，由于JSON不包括类型信息，它在去串行化时对类型进行了最佳猜测，但我本以为在MockMvcResultMatchers中执行比较时会有一种方法强制提取类型。

完整代码如下，但测试为：

@Test
public void testGetObjectWithLong() throws Exception {
    Long id = 45l;
    ObjectWithLong objWithLong = new ObjectWithLong(id);
    Mockito.when(service.getObjectWithLong(String.valueOf(id))).thenReturn(objWithLong);
    mockMvc.perform(MockMvcRequestBuilders.get("/Test/" + id))
    .andExpect(MockMvcResultMatchers.status().isOk())
    .andExpect(MockMvcResultMatchers.jsonPath("$longvalue")
        .value(Matchers.isA(Long.class)))
    .andExpect(MockMvcResultMatchers.jsonPath("$longvalue")
        .value(Matchers.equalTo(id)));
}

结果是：

java.lang.AssertionError: JSON path$longvalue
Expected: is an instance of java.lang.Long
   but: <45> is a java.lang.Integer
at org.springframework.test.util.MatcherAssertionErrors.assertThat(MatcherAssertionErrors.java:80)
...

任何关于解决这一问题的正确方法的想法或建议都将不胜感激。显然，我可以将Integer.MAX_VALUE添加到测试中的id字段中，但这似乎很脆弱。

提前谢谢。

除了第三方库之外，以下内容应为独立内容

import org.hamcrest.Matchers;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.mockito.MockitoAnnotations;
import org.mockito.runners.MockitoJUnitRunner;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.stereotype.Service;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.result.MockMvcResultMatchers;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
@RunWith(MockitoJUnitRunner.class)
public class TestControllerTest {
    private MockMvc mockMvc;
    @Mock
    private RandomService service;
    @InjectMocks
    private TestController controller = new TestController();
    @Before
    public void setUp() {
        MockitoAnnotations.initMocks(this);
        mockMvc = MockMvcBuilders.standaloneSetup(controller)
            .setMessageConverters(new MappingJackson2HttpMessageConverter())
            .build();
    }
    @Test
    public void testGetObjectWithLong() throws Exception {
        Long id = 45l;
        ObjectWithLong objWithLong = new ObjectWithLong(id);
        Mockito.when(service.getObjectWithLong(String.valueOf(id))).thenReturn(objWithLong);
        mockMvc.perform(MockMvcRequestBuilders.get("/Test/" + id))
        .andExpect(MockMvcResultMatchers.status().isOk())
        .andExpect(MockMvcResultMatchers.jsonPath("$longvalue").value(Matchers.isA(Long.class)))
        .andExpect(MockMvcResultMatchers.jsonPath("$longvalue").value(Matchers.equalTo(id)));
    }
    @RestController
    @RequestMapping(value = "/Test")
    private class TestController {
        @Autowired
        private RandomService service;
        @RequestMapping(value = "/{id}", method = RequestMethod.GET)
        public ObjectWithLong getObjectWithLong(@PathVariable final String id) {
            return service.getObjectWithLong(id);
        }
    }
    @Service
    private class RandomService {
        public ObjectWithLong getObjectWithLong(String id) {
            return new ObjectWithLong(Long.valueOf(id));
        }
    }
    private class ObjectWithLong {
        private Long longvalue;
        public ObjectWithLong(final Long theValue) {
            this.longvalue = theValue;
        }
        public Long getLongvalue() {
            return longvalue;
        }
        public void setLongvalue(Long longvalue) {
            this.longvalue = longvalue;
        }
    }
}

Answer 1

您可以使用anyOf Matcher以及针对Number超类的class匹配，并将其设置为

.andExpect(MockMvcResultMatchers.jsonPath("$longvalue")
        .value(Matchers.isA(Number.class)))
.andExpect(MockMvcResultMatchers.jsonPath("$longvalue")
        .value(Matchers.anyOf(
            Matchers.equalTo((Number) id),
            Matchers.equalTo((Number) id.intValue()))));