Question

我正在尝试将地图从http响应转换为POJO。回复是

{_total=0}

在我的Pojo中，我想摆脱下划线，所以我用@JsonProperty注释了该字段。但是Groovy抱怨没有_total属性

堆栈跟踪

org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object '{_total=0}' with class 'java.util.LinkedHashMap' to class 'io.toro.linkedin.response.CompanyAdminsResponse' due to: org.codehaus.groovy.runtime.metaclass.MissingPropertyExceptionNoStack: No such property: _total for class: io.toro.linkedin.response.CompanyAdminsResponse
Possible solutions: total

    at io.toro.linkedin.connector.LinkedInConnector.linkedInListCompaniesThatUserIsAdminOf(LinkedInConnector.groovy:314)
    at LinkedInTest.list-companies-that-user-is-admin-of(LinkedInTest.groovy:115)

转换代码

HttpResponseDecorator response = restClient.get(params)
ObjectMapper mapper = new ObjectMapper()
mapper.convertValue(response.data as Map, T)

POJO

package io.toro.linkedin.response

import com.fasterxml.jackson.annotation.JsonProperty
import groovy.transform.ToString
import io.toro.linkedin.model.Company

/**
 * @author daniel.gomez
 */
@ToString(includeNames = true)
class CompanyAdminsResponse {
    @JsonProperty('_count')
    int count
    @JsonProperty('_start')
    int start
    @JsonProperty('_total')
    int total
    List<Company> values
}

Answer 1

我认为问题来自您对Map的响应转换：response.data as Map您传递给mapper.convertValue方法。

我直接使用跟随Map [_total : 3]制作一个groovy脚本来测试您的问题，并且没有异常抛出正确创建的对象：

@Grab('com.fasterxml.jackson.core:jackson-core:2.7.3')
@Grab('com.fasterxml.jackson.core:jackson-annotations:2.7.3')
@Grab('com.fasterxml.jackson.core:jackson-databind:2.7.3')
@GrabExclude('org.codehaus.groovy:groovy-all')

import com.fasterxml.jackson.annotation.JsonProperty
import com.fasterxml.jackson.databind.ObjectMapper
import groovy.transform.ToString

class Company {
}

@ToString(includeNames = true)
class CompanyAdminsResponse {
    @JsonProperty('_count')
    int count
    @JsonProperty('_start')
    int start
    @JsonProperty('_total')
    int total
    List<Company> values
}

ObjectMapper mapper = new ObjectMapper()
def object = [_total : 3]
println mapper.convertValue(object, CompanyAdminsResponse) 
// the above line prints CompanyAdminsResponse(count:0, start:0, total:3, values:null)

希望这有帮助，

使用Jackson将地图转换为POJO，Groovy抱怨没有财产

1 个答案: