Java中使用Thrift的异步请求

Question

我正在寻找如何使用 Thrift 在 Java 中发出异步请求的示例。查看生成的代码，这似乎是可能的，但我找不到一个示例。

下面是一个表明存在异步接口的生成代码示例：

...
AsyncIface {
    public static class Factory implements org.apache.thrift.async.TAsyncClientFactory<AsyncClient> {
      private org.apache.thrift.async.TAsyncClientManager clientManager;
      private org.apache.thrift.protocol.TProtocolFactory protocolFactory;
      public Factory(org.apache.thrift.async.TAsyncClientManager clientManager, org.apache.thrift.protocol.TProtocolFactory protocolFactory) {
        this.clientManager = clientManager;
        this.protocolFactory = protocolFactory;
      }
      public AsyncClient getAsyncClient(org.apache.thrift.transport.TNonblockingTransport transport) {
        return new AsyncClient(protocolFactory, clientManager, transport);
      }
    }
 ...

关于如何使用它的任何指针？

Answer 1

使用上面的接口进行这样的异步调用（代码中提到了 Cassandra，但很容易推广到您的应用程序）：

TNonblockingTransport transport = new TNonblockingSocket("127.0.0.1", 9160);
TAsyncClientManager clientManager = new TAsyncClientManager();
TProtocolFactory protocolFactory = new TBinaryProtocol.Factory();
Cassandra.AsyncClient client = new Cassandra.AsyncClient(protocolFactory, clientManager, transport);

Cassandra.method_call(parameters, new Callback());

Answer 2

你没有给出任何上下文，所以我会给你你需要的基本部分：

• 要执行异步调用，您需要在线程中进行调用
• 要获得结果，您需要某种回调方式

以下是这些元素的基本示例：

final MyClient client;  // Who will get a call back to the their sendResult() method when asynch call finished
ExecutorService executor = Executors.newSingleThreadExecutor(); // Handy way to run code in a thread
Runnable task = new Runnable() { 
    public void run() { // Where the "do the call" code sits
        int result = someService.call(someParamter);
        client.sendResult(result); // For example, expecting an int result
    }
};
executor.submit(task); // This scheduled the runnable to be run