如何断言json路径值大于值?

问题描述

给定从 REST 调用返回的以下 JSON:

{"Statistik Eintraege":
[{"Wert":"1","Anzahl":41},{"Wert":"","Anzahl":482},{"Wert":"-3","Anzahl":1},{"Wert":"-1","Anzahl":3},{"Wert":"-2","Anzahl":3}],"Statistik Typ":"BlahStatistik"}

...我想验证 Wert='' 的 'Anzahl' 是否大于 400(在本例中为:482)。

我在 java 集成测试中尝试的是:

.andExpect(jsonPath("$..[?(@.Wert == '')].Anzahl",greaterThan(400)));

The exception:

java.lang.classCastException: class net.minidev.json.JSONArray cannot be cast to class java.lang.Comparable (net.minidev.json.JSONArray is in unnamed module of loader 'app'; java.lang.Comparable is in module java.base of loader 'bootstrap')

    at org.hamcrest.comparator.ComparatorMatcherBuilder$1.compare(ComparatorMatcherBuilder.java:22)
    at org.hamcrest.comparator.ComparatorMatcherBuilder$ComparatorMatcher.describeMismatchSafely(ComparatorMatcherBuilder.java:86)
    at org.hamcrest.TypeSafeMatcher.describeMismatch(TypeSafeMatcher.java:82)
    at org.hamcrest.MatcherAssert.assertthat(MatcherAssert.java:18)
    at org.springframework.test.util.JsonPathExpectationsHelper.assertValue(JsonPathExpectationsHelper.java:74)
    at org.springframework.test.web.servlet.result.JsonPathResultMatchers.lambda$value$0(JsonPathResultMatchers.java:87)
    at org.springframework.test.web.servlet.mockmvc$1.andExpect(mockmvc.java:196)
    at 

我还能尝试什么?

解决方法

JsonPath 运算符 [?(<expression>)] 选择与给定表达式匹配的所有元素。因此,结果是一个json数组。

在示例中,[?(@.Wert == '')] 匹配所有具有空值字段 Wert 的 json 节点。您的 json 示例只有一个与谓词匹配的项目,但通常可能有多个。要解决此问题,您必须定义一个仅匹配单个元素的更具体的表达式,或者调整匹配器以处理集合。

匹配集合:

.andExpect(jsonPath("$..[?(@.Wert == '')].Anzahl",everyItem(greaterThan(400))))