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我有一个小程序，我必须向 Web 应用程序发送一个请求，以从数据库中的服务器获取数据。我正在处理对象，服务器用对象响应我非常有用！

小程序如何与服务器通信？

我认为 Web 服务方法、RMI 和...让我很开心，但哪个是最好和可靠的？

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1 回答 1

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只要它只有您的小程序与服务器通信，您就可以使用序列化对象。您只需要在applet jar 和服务器上维护相同版本的对象类。它不是最开放或可扩展的方式，但就开发时间而言它很快并且非常可靠。

这是一个例子。

实例化与 servlet 的连接

URL servletURL = new URL("<URL To your Servlet>");
URLConnection servletConnect = servletURL.openConnection();
servletConnect.setDoOutput(true); // to allow us to write to the URL
servletConnect.setUseCaches(false); // Write the message to the servlet and not from the browser's cache
servletConnect.setRequestProperty("Content-Type","application/x-java-serialized-object");

获取输出流并写入您的对象

MyCustomObject myObject = new MyCustomObject()
ObjectOutputStream outputToServlet;
outputToServlet = new ObjectOutputStream(servletConnection.getOutputStream());
outputToServlet.writeObject(myObject);
outputToServlet.flush(); //Cleanup
outputToServlet.close();

现在阅读响应

ObjectInputStream in = new ObjectInputStream(servletConnection.getInputStream());
MyRespObject myrespObj;
try
{
    myrespObj= (MyRespObject) in.readObject();
} catch (ClassNotFoundException e1)
{
    e1.printStackTrace();
}

in.close();

在您的 servlet 中

public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
  MyRespObject myrespObj= processSomething(request);
  response.reset();
  response.setHeader("Content-Type", "application/x-java-serialized-object");
  ObjectOutputStream outputToApplet;
  outputToApplet = new ObjectOutputStream(response.getOutputStream());
  outputToApplet.writeObject(myrespObj);
  outputToApplet.flush();
  outputToApplet.close();
}

private MyRespObject processSomething(HttpServletRequest request)
{
  ObjectInputStream inputFromApplet = new ObjectInputStream(request.getInputStream());
  MyCustomObject myObject = (MyCustomObject) inputFromApplet.readObject();
  //Do Something with the object you just passed
  MyRespObject myrespObj= new MyRespObject();
  return myrespObj;
}

请记住，您传递的两个对象都需要实现可序列化

 public Class MyCustomObject implements java.io.Serializable
 {
于 2009-09-08T19:22:35.277 回答