GSON 抛出 Expected BEGIN_ARRAY 但是是 BEGIN_OBJECT 错误 [重复]答案

【问题标题】：GSON throws Expected BEGIN_ARRAY but was BEGIN_OBJECT error [duplicate]GSON 抛出 Expected BEGIN_ARRAY 但是是 BEGIN_OBJECT 错误 [重复]
【发布时间】：2016-05-16 14:21:17
【问题描述】：

我正在使用 GSON 进行改造和解析结果。不知道为什么，我收到了这个

应为 BEGIN_ARRAY，但在第 1 行第 2 列路径中为 BEGIN_OBJECT

我知道这个错误是什么意思，但不明白原因。

这是我的 json 响应

{"suggestions": [
{
  "value": "г Казань",
  "unrestricted_value": "Респ Татарстан, г Казань",
  "data": {
    "qc_complete": null,
    "qc_house": null,
    "qc_geo": "4",
    "postal_code": "420000",
    "postal_box": null,
    "country": "Россия",
    "region_fias_id": null,
    "region_kladr_id": null,
    "region_with_type": "Респ Татарстан",
    "region_type": "Респ",
    "region_type_full": "республика",
    "region": "Татарстан",
    "area_fias_id": null,
    "area_kladr_id": null,
    "area_with_type": null,
    "area_type": null,
    "area_type_full": null,
    "area": null,
    "city_fias_id": null,
    "city_kladr_id": null,
    "city_with_type": "г Казань",
    "city_type": "г",
    "city_type_full": "город",
    "city": "Казань",
    "city_district": null,
    "settlement_fias_id": null,
    "settlement_kladr_id": null,
    "settlement_with_type": null,
    "settlement_type": null,
    "settlement_type_full": null,
    "settlement": null,
    "street_fias_id": null,
    "street_kladr_id": null,
    "street_with_type": null,
    "street_type": null,
    "street_type_full": null,
    "street": null,
    "house_fias_id": null,
    "house_kladr_id": null,
    "house_type": null,
    "house_type_full": null,
    "house": null,
    "block_type": null,
    "block_type_full": null,
    "block": null,
    "flat_area": null,
    "square_meter_price": null,
    "flat_price": null,
    "flat_type": null,
    "flat_type_full": null,
    "flat": null,
    "fias_id": "93b3df57-4c89-44df-ac42-96f05e9cd3b9",
    "fias_level": "4",
    "kladr_id": "1600000100000",
    "tax_office": "1600",
    "tax_office_legal": null,
    "capital_marker": "2",
    "okato": "92401000000",
    "oktmo": "92701000",
    "timezone": null,
    "geo_lat": "55.7943051",
    "geo_lon": "49.1116709",
    "beltway_hit": null,
    "beltway_distance": null,
    "unparsed_parts": null,
    "qc": null
  }
} ]}

这是我用 pojogenerator 生成的模型。

public class DadataResponse {

@SerializedName("suggestions")
@Expose
private List<Suggestion> suggestions = new ArrayList<Suggestion>();

/**
 * 
 * @return
 *     The suggestions
 */
public List<Suggestion> getSuggestions() {
    return suggestions;
}

/**
 * 
 * @param suggestions
 *     The suggestions
 */
public void setSuggestions(List<Suggestion> suggestions) {
    this.suggestions = suggestions;
}

}

public class Suggestion {

@SerializedName("value")
@Expose
private String value;
@SerializedName("unrestricted_value")
@Expose
private String unrestrictedValue;
@SerializedName("data")
@Expose
private Data data;

/**
 * 
 * @return
 *     The value
 */
public String getValue() {
    return value;
}

/**
 * 
 * @param value
 *     The value
 */
public void setValue(String value) {
    this.value = value;
}

/**
 * 
 * @return
 *     The unrestrictedValue
 */
public String getUnrestrictedValue() {
    return unrestrictedValue;
}

/**
 * 
 * @param unrestrictedValue
 *     The unrestricted_value
 */
public void setUnrestrictedValue(String unrestrictedValue) {
    this.unrestrictedValue = unrestrictedValue;
}

/**
 * 
 * @return
 *     The data
 */
public Data getData() {
    return data;
}

/**
 * 
 * @param data
 *     The data
 */
public void setData(Data data) {
    this.data = data;
}

}

还有数据类，但是太大了，不需要贴在这里。

那么为什么我会收到这个错误？请帮忙

更新

public ApiService(String URLSTRING){

    RequestInterceptor requestInterceptor = new RequestInterceptor() {
        @Override
        public void intercept(RequestFacade request) {
            request.addHeader("Authorization", "Token");
            request.addHeader("Content-Type","application/json");
            request.addHeader("Accept","application/json");
        }
    };

    RestAdapter restAdapter = new RestAdapter.Builder()
            .setEndpoint(URLSTRING)
                    .setRequestInterceptor(requestInterceptor)
            .setLogLevel(RestAdapter.LogLevel.FULL)
            .build();

    mApi = restAdapter.create(Api.class);
}

 public interface Api{

    @GET("/address")
    List<DadataResponse> getDadata(@Query("query") String query);

 }

【问题讨论】：

这里缺少的是调用gson解析json的代码。您的类型标记可能是错误的。
只有一件事，伙计。快试试吧
@njzk2 我添加了改造电话
@vzamanillo 这是相反的情况（但是，是的，已经问了无数次）......显然 gson 期望 List 但 json 是单个对象
我没有写 suggestions 是单个对象...根(DadataResponse) 是单个对象

标签： java android gson retrofit

【解决方案1】：

改变

List<DadataResponse> getDadata(@Query("query") String query);

到

DadataResponse getDadata(@Query("query") String query);

应为 BEGIN_ARRAY，但在第 1 行第 2 列路径中为 BEGIN_OBJECT

意味着它期待一个数组（因为你告诉它）但它收到了一个对象。

您似乎收到了一个DadataResponse，而不是它们的数组，因此您需要更新您的签名以匹配现实。

【讨论】：