[英]GSON parse a JSON value
我正在處理以 Java 編寫的 web 服務,我必須從 JSON 格式獲得響應。 以下是 JSON。如何正確獲取這些值以便使用它們?
{
"message": "string",
"validationErrors": [
{
"code": "string",
"message": "string"
}
],
"exceptionMessages": [
{
"code": "string",
"message": "string"
}
],
"trailId": "string",
"isSuccessful": true
}
這就是我正在嘗試的,但我遇到了錯誤。
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import java.lang.reflect.Type;
Type listErrors = new TypeToken<List<Response>>() {}.getType();
List<Response> list = gson.fromJson(response.toString(), listErrors);
這是我在測試時遇到的錯誤。
com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $
響應.java
import java.util.List;
public class Response{
public Response() {
super();
}
private String message;
private List<ValidationErrors> errors;
public void setMessage(String message) {
this.message = message;
}
public String getMessage() {
return message;
}
public void setErrors(List<ValidationErrors> errors) {
this.errors = errors;
}
public List<ValidationErrors> getErrors() {
return errors;
}
}
驗證錯誤.java
public class ValidationErrors {
public ValidationErrors() {
super();
}
private String code;
private String message;
public void setCode(String code) {
this.code = code;
}
public String getCode() {
return code;
}
public void setMessage(String message) {
this.message = message;
}
public String getMessage() {
return message;
}
}
正如我的理解是正確的,你只得到一個 object,而不是列表:
Response result = gson.fromJson(response.toString(), Response.class);
要 map object correctl,您還必須重命名屬性,以便它們適合 json 結構中的鍵名:
import java.util.List;
public class Response{
public Response() {
super();
}
private String message;
private List<ValidationErrors> validationErrors;
public void setMessage(String message) {
this.message = message;
}
public String getMessage() {
return message;
}
public void setValidationErrors(List<ValidationErrors> errors) {
this.validationErrors = errors;
}
public List<ValidationErrors> getValidationErrors() {
return errors;
}
}
或為其添加SerializedName
注解:
import java.util.List;
public class Response{
public Response() {
super();
}
private String message;
@SerializedName("validationErrors")
private List<ValidationErrors> errors;
public void setMessage(String message) {
this.message = message;
}
public String getMessage() {
return message;
}
public void setErrors(List<ValidationErrors> errors) {
this.errors = errors;
}
public List<ValidationErrors> getErrors() {
return errors;
}
}
並為缺少的鍵exceptionMessages
、 trailId
和isSuccessful
添加屬性。
您收到此錯誤,因為您的 json 響應是 object 並且您正在嘗試解析,因為它是一個數組,但它不是..
這就是為什么它顯示為com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was BEGIN_OBJECT at line 1 column 2 path $
你應該替換下面提到的代碼
從
Type listErrors = new TypeToken<List<Response>>() {}.getType();
List<Response> list = gson.fromJson(response.toString(), listErrors);
到
Response objectResponse = gson.fromJson(response.toString(), Response.class);
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.