Java异常-第n次尝试返回到 "try"语句 block

Question

我正在尝试进行一个可能因服务器关闭而引发异常的调用。这就是我想要实现的目标:

Server server = serverQueue.poll();
try {
     if (server==null){return null}
     server.makeConnection();

} catch (Exception e) {
     // try another server
     server = serverQueue.poll();
     // now return to try block?

}

所以我有 5 台服务器，也许在后期我会添加更多。所以我想连接到他们中的任何一个人都以这种方式。我怎样才能返回到try block ？ java中有没有像下面这样的语句？:

Server server = serverQueue.poll();
outerBlock:
try {
     if (server==null){return null}
     server.makeConnection();

} catch (Exception e) {
     // try another server
     server = serverQueue.poll();
     continue outerBlock;

}

Answer 1

基本上是一个循环:

Server server = serverQueue.poll();
boolean connected = false;
while (!connected) {
    if (server == null) {
        return null;
    }
    try {
         server.makeConnection();
         connected = true;
    } catch (Exception e) {
         // Presumably log something here, for management info

         // try another server
         server = serverQueue.poll();
    }
}

或者避免重复:

Server server;
boolean connected = false;
while (!connected) {
    server = serverQueue.poll();
    if (server == null) {
        return null;
    }
    try {
         server.makeConnection();
         connected = true;
    } catch (Exception e) {
         // Presumably log something here, for management info
    }
}

您可能会考虑将其中的“查找服务器”部分隔离到其自己的功能中。