RestEasy：org.codehaus.jackson.map.JsonMappingException：无法从START_OBJECT标记(..)中反序列化java.util.ArrayList

我有一个休息端点返回List< VariablePresentation>.我试图测试这个休息端点为

    @Test
    public void testGetAllVariablesWithoutQueryParamPass() throws Exception {
        final ClientRequest clientCreateRequest = new ClientRequest("http://localhost:9090/variables");
        final MultivaluedMap<String, String> formParameters = clientCreateRequest.getFormParameters();
        final String name = "testGetAllVariablesWithoutQueryParamPass";
        formParameters.putSingle("name", name);
        formParameters.putSingle("type", "String");
        formParameters.putSingle("units", "units");
        formParameters.putSingle("description", "description");
        formParameters.putSingle("core", "true");

        final GenericType<List<VariablePresentation>> typeToken = new GenericType<List<VariablePresentation>>() {
        };
        final ClientResponse<List<VariablePresentation>> clientCreateResponse = clientCreateRequest.post(typeToken);
        assertEquals(201, clientCreateResponse.getStatus());
        final List<VariablePresentation> variables = clientCreateResponse.getEntity();
        assertNotNull(variables);
        assertEquals(1, variables.size());

    }

此测试失败并显示错误

org.codehaus.jackson.map.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of START_OBJECT token(..)

我该如何解决这个问题？

解决方法:

这看起来像是一个Jackson错误,它期望解析一个数组(以'[‘开头),但它遇到一个对象的开始标记(‘{‘).从查看你的代码,我猜它正在尝试将JSON反序列化到你的List中,但是它获得了一个对象的JSON.

REST端点返回的JSON是什么样的？应该看起来像这样

[
    {
        // JSON for VariablePresentation value 0
        "field0": <some-value>
        <etc...>
    },
    <etc...>
]

标签：java,unit-testing,jackson,resteasy
来源： https://codeday.me/bug/20190825/1723859.html