Java连接Get请求异常处理

Question

我尝试向网站发送 GET 请求，如下所示:

uRL = new URL(URLString);
connection = (HttpURLConnection) uRL.openConnection();    
// optional default is GET
connection.setRequestMethod("GET");    
// add request header
connection.setRequestProperty("User-Agent", USER_AGENT);    
responseCode = connection.getResponseCode();

但是，我需要处理异常。例如，如果抛出异常，那么我将尝试再次请求。我怎样才能做到这一点？

Answer 1

您可以将 while 与 try-catch 一起使用，因此如果发生异常，则转到下一次迭代，否则break 循环

int attempts=5;
boolean flag=false;
while(attempts-- > 0){
  try{
   uRL = new URL(URLString);
   connection = (HttpURLConnection) uRL.openConnection();    
   connection.setRequestMethod("GET");    
   connection.setRequestProperty("User-Agent", USER_AGENT);    
   responseCode = connection.getResponseCode();
   flag=ture;
    break;
  }catch(Exception e){
      e.printStackTrace();
      continue;
    }
}


 if(flag){
     // mean request executed successfully 
     // don't throw exception, unless you want to break the current flow of execution
    }

要限制尝试次数，只需使用计数变量(尝试)和标志变量来验证是否成功执行