线程“main”java.lang.ClassCastException 中的异常：类 java.util.LinkedHashMap 无法转换为类 java.util.List

Question

When working with REST Assured Java framework, I get the following error.

Exception in thread "main" java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class java.util.List (java.util.LinkedHashMap and java.util.List are in module java.base of loader 'bootstrap')
    at io.restassured.path.json.JsonPath.getList(JsonPath.java:375)
    at qaflightsuppliers.QaFlightDXBLONResponseDebugValidation.main(QaFlightDXBLONResponseDebugValidation.java:94)

Below is my code. Please correct my code.

List<String> jsonMapStringObjectResponse = response.jsonPath().get("recommendation");
        
for (int i = 0; i <= jsonMapStringObjectResponse.size(); i++)
{
    List<String> jsonMapObjectResponse = response.jsonPath().getList("recommendation[" + i + "]");
    System.out.print("ValidatingAirlineName="+jsonMapObjectResponse.add("validatingAirlineName"));
}   

Answer 1

You are trying to read the attribute recommendation as a List , but in reality in the JSON response it's a Map .

So you have to change:

List<String> jsonMapObjectResponse = response.jsonPath().getList("recommendation[" + i + "]");

to

Map<String, String> jsonMapObjectResponse = response.jsonPath().getMap("recommendation[" + i + "]");
// example below
System.out.println(jsonMapObjectResponse.get("validatingAirlineName"));

Reverse engineered from this question your JSON probably looks something like this:

[
  {
    "id": 1,
    "recommendation": {
      "validatingAirlineName": "...",
      "adultBaseFare": "...",
      "adultTaxFare": "..."
    }
  },
  {
    "id": 2,
    "recommendation": {
      "validatingAirlineName": "...",
      "adultBaseFare": "...",
      "adultTaxFare": "..."
    }
  }
]

Tested and verified with this demo, which might be a good reading resource as well:

• https://devqa.io/parse-json-response-rest-assured/