Question

我正在使用改造来从我的API接收JSON数据。当数据包含单个对象时，我能够接收JSON数据。但当我尝试获取所有员工的清单时，我收到了错误。

/ api / Employee / 1的JSON数据是（正常工作）：

{
  "id": 10,
  "name": "Arpit",
  "number": "7777777777",
  "city": "noida",
  "depid": 4,
}

获取此JSON对象的代码正在运行。 PFB代码。

改造代码：

public void onResponse(Response<EmployeeResponse> response, Retrofit retrofit) {
    if (response.raw().toString()!=null) {
        Employee e = new Employee();
        e.setId(response.body().id);
        e.setName(response.body().name);
        e.setCity(response.body().city);
        e.setNumber(response.body().number);
        Log.d("employee details", e.toString());
        list.add(e);
        rv.setAdapter(new SimpleItemRecyclerViewAdapter(list));
    }
    else
        Log.d("No data recieved",response.raw().toString());
}

@Override
public void onFailure(Throwable t) {
    Log.d("Fail",t.getMessage());}

EmployeeAPI.java

public interface EmployeeAPI {
@GET("/assignment1/api/Employee/1")
Call<EmployeeResponse> load_employee();}

EmployeeResponse.java

public class EmployeeResponse {
@SerializedName("id")
public String id;
@SerializedName("name")
public String name;
@SerializedName("city")
public String city;
@SerializedName("number")
public String number;}

但是当我试图从/ api / Employee获取所有员工的列表时，我收到以下错误：

java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2 path $

api / Employee的JSON数据是（）：

[  
   {  
  "id":10,
  "name":"Arpit Jain",
  "number":"7777777777",
  "city":"noida",
  "depid":4,
   },
   {  
  "id":32,
  "name":"Ish Chawla",
  "number":"9999999999",
  "city":"Noida",
  "depid":1,
   },
   {  
  "id":39,
  "name":"Laxman",
  "number":"6666666666",
  "city":"GZB",
  "depid":1,
   },
   {  
  "id":44,
  "name":"Ishan",
  "number":"9839060055",
  "city":"Kanpur",
  "depid":3,
   }
]

获取员工名单的代码是：

改造代码

public void onResponse(Response<EmployeeResponse> response, Retrofit retrofit) {
    if (response.raw().toString()!=null) {
        Log.d("employee details", response.body().toString());
        list = response.body().list;
        rv.setAdapter(new SimpleItemRecyclerViewAdapter(list));
    }
    else
        Log.d("No data recieved",response.raw().toString());
}

@Override
public void onFailure(Throwable t) {
    Log.d("Fail",t.getMessage());
}

EmployeeAPI.java

 public interface EmployeeAPI {
    @GET("/assignment1/api/Employee")
    Call<EmployeeResponse> load_employee();
}

EmployeeResponse.java

   public class EmployeeResponse {
    public ArrayList<Employee> list;
}

请告诉我正确获取数据所需的更改。

Answer 1

因为您正在获取整个员工列表及其数组。

  public interface EmployeeAPI {
     @GET("/assignment1/api/Employee")
     Call<Employee[]> load_employee();

     @GET("/assignment1/api/Employee/1")
     Call<Employee> load_employee();
    }

并且不要创建EmployeeResponse类。在Employee pojo类中使用@SerializedName。

收到回复后

if (response.raw().toString()!=null) {
        Employee e = new Employee();
        e.setId(response.body().id);
        e.setName(response.body().name);
        e.setCity(response.body().city);
        e.setNumber(response.body().number);
        Log.d("employee details", e.toString());
        list.add(e);
        rv.setAdapter(new SimpleItemRecyclerViewAdapter(list));
    }

不需要设置它。

Answer 2

public class EmployeeResponse {
   @SerializedName("id") 
   public String id; 
   @SerializedName("name")
   public String name;
   @SerializedName("city")
   public String city;
   @SerializedName("number")
   public String number;
}

使用上面的类作为模型

public interface EmployeeAPI {
  @GET("/assignment1/api/Employee")
  Call<ArrayList<EmployeeResponse>> load_employee();
}

并且由于您返回列表，因此调用对象接受列表以接受员工列表

Answer 3

您需要在代码中进行少量更改：

1）的 EmployeeResponse.java

public class EmployeeResponse { public List<Employee> list; public List<Employee> getDatas() { return datas; } }

2） Employee.java

public class Employee{ @SerializedName("id") public String id; @SerializedName("name") public String name; @SerializedName("city") public String city; @SerializedName("number") public String number; public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getCity() { return city; } public void setCity(String city) { this.city = city; } public String getNumber() { return number; } public void setNumber(String number) { this.number = number; } }

3）在界面中：

public interface EmployeeAPI { @GET("/assignment1/api/Employee") Call<EmployeeResponse> load_employee(); }

4）改造代码

private void getEmployee() { List<Employee> employee; if (retrofit == null) { retrofit = new Retrofit.Builder() .baseUrl(BASE_URL) .addConverterFactory(GsonConverterFactory.create()) .build(); } EmployeeAPI apiInterface = retrofit.create(EmployeeAPI.class); Call<EmployeeResponse> call = apiInterface.load_employee(); call.enqueue(new Callback<EmployeeResponse>() { @Override public void onResponse(Call<EmployeeResponse> call, Response<EmployeeResponse> response) { employee = response.body().getDatas(); } @Override public void onFailure(Call<EmployeeResponse> call, Throwable t) { Log.e(TAG, "onFailure:" + t.getMessage()); } }); }

发出GET请求时，Retrofit会返回null响应正文

3 个答案: