Backendless 中 'Internal client exception' 的原因是什么？

Question

我有table任务： enter image description here

我想在这个 table 中获取记录。但是有一个BackendlessException { code: 'Internal client exception', message: 'null' }

这是我的代码：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_task);

    Backendless.initApp(getApplicationContext() ,APP_ID, SECRET_KEY, VERSION);


    BackendlessCollection<Task> tasks = Backendless.Data.of(Task.class).find();

    System.out.println( "Size " + tasks.getCurrentPage().size() );


    Iterator<Task> iterator = tasks.getCurrentPage().iterator();

    while (iterator.hasNext())
    {
        Task t = iterator.next();
        System.out.println("Question = " + t.getQuestion());
        System.out.println("Answer =  " + t.getAnswer());
    }





}

Task.class:

   public class Task {
    public String Question ;
    public  String Answer ;
    public  String ownerId ;
    public    String objectId ;
    public   Date created ;
    public Date updated ;
    public Task()
    {

    }
    public Task(String Question ,String Answer)
    {
        this.Question = Question ;
        this.Answer = Answer ;

    }




}

我从 Backendless 文档中了解到这个查询。这个错误的原因是什么？如何避免这个错误？在从 Backedless 检索数据之前是否需要了解一些规则？

Answer 1

您正在此处的 UI 主线程上调用同步（阻塞）API：

BackendlessCollection<Task> tasks = Backendless.Data.of(Task.class).find();

为避免错误，要么创建一个单独的线程并在其中使用 API，要么将调用更改为异步版本。

API documentation 说：

Android applications cannot use synchronous APIs on the main UI thread. The reason for this is the main thread does not allow blocking calls. Since the API requests perform network-based communication, the naturally block. As a result, when using the Backendless APIs make sure to use the asynchronous version of the methods, or create a new thread and use the synchronous API in it

Backendless 中 'Internal client exception' 的原因是什么？

What is the reason of 'Internal client exception' in Backendless?

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