相关疑难解决方法(0)

在下面的代码片段中,我有一个递归函数调用,用于在网络调用失败时促进重试(Amazon SimpleDB偶尔会返回503并需要重试.)

当我尝试编译时,Scala抱怨道recursive method simpledb_update needs result type.

// sends data to SimpleDB. Retries if necessary
def simpledb_update(name: String, metadata: Map[String,String], attempt: Int) = {
 try {
  db(config("simpledb_db")) += (name, metadata)
 } catch {
  case e =>
   // if it fails, try again up to 5 times
  if(attempt < 6)
  {
   Thread.sleep(500)
   simpledb_update(name, metadata, attempt + 1)
   } else
     AUlog(name + ": SimpleDB Failed")
   }
 }

为什么递归函数需要这个？我的想法是只返回一个true/false布尔值来满足编译器...以下编译很好.

// sends data to SimpleDB. Retries if necessary
 def simpledb_update(name: String, …