Java RMI - GUI应用程序( GUI Application)

在上一章中，我们创建了一个示例RMI应用程序。在本章中，我们将解释如何创建RMI应用程序，其中客户端调用显示GUI窗口（JavaFX）的方法。

定义远程接口

在这里，我们使用名为animation()的方法定义一个名为Hello的远程接口。

import java.rmi.Remote; 
import java.rmi.RemoteException;  
// Creating Remote interface for our application 
public interface Hello extends Remote { 
   void animation() throws RemoteException; 
}

开发实现类

在此应用程序的Implementation类（远程对象）中，我们尝试使用JavaFX创建一个显示GUI内容的窗口。

import javafx.animation.RotateTransition;  
import javafx.application.Application;  
import javafx.event.EventHandler;   
import javafx.scene.Group;  
import javafx.scene.PerspectiveCamera;  
import javafx.scene.Scene;  
import javafx.scene.control.TextField;  
import javafx.scene.input.KeyEvent;  
import javafx.scene.paint.Color;  
import javafx.scene.paint.PhongMaterial; 
import javafx.scene.shape.Box;  
import javafx.scene.text.Font;  
import javafx.scene.text.FontWeight;
import javafx.scene.text.Text;   
import javafx.scene.transform.Rotate;  
import javafx.stage.Stage;  
import javafx.util.Duration;  
// Implementing the remote interface 
public class FxSample extends Application implements Hello {  
   @Override  
   public void start(Stage stage) { 
      // Drawing a Box  
      Box box = new Box();  
      // Setting the properties of the Box  
      box.setWidth(150.0);  
      box.setHeight(150.0);    
      box.setDepth(100.0);  
      // Setting the position of the box  
      box.setTranslateX(350);   
      box.setTranslateY(150);  
      box.setTranslateZ(50);  
      // Setting the text  
      Text text = new Text(
         "Type any letter to rotate the box, and click on the box to stop the rotation");
      // Setting the font of the text  
      text.setFont(Font.font(null, FontWeight.BOLD, 15));      
      // Setting the color of the text  
      text.setFill(Color.CRIMSON);  
      // Setting the position of the text  
      text.setX(20);  
      text.setY(50); 
      // Setting the material of the box  
      PhongMaterial material = new PhongMaterial();   
      material.setDiffuseColor(Color.DARKSLATEBLUE);   
      // Setting the diffuse color material to box  
      box.setMaterial(material);        
      // Setting the rotation animation to the box     
      RotateTransition rotateTransition = new RotateTransition();  
      // Setting the duration for the transition  
      rotateTransition.setDuration(Duration.millis(1000));  
      // Setting the node for the transition  
      rotateTransition.setNode(box);        
      // Setting the axis of the rotation  
      rotateTransition.setAxis(Rotate.Y_AXIS);  
      // Setting the angle of the rotation 
      rotateTransition.setByAngle(360);  
      // Setting the cycle count for the transition  
      rotateTransition.setCycleCount(50);  
      // Setting auto reverse value to false  
      rotateTransition.setAutoReverse(false);   
      // Creating a text filed  
      TextField textField = new TextField();    
      // Setting the position of the text field  
      textField.setLayoutX(50);  
      textField.setLayoutY(100);  
      // Handling the key typed event  
      EventHandler<KeyEvent> eventHandlerTextField = new EventHandler<KeyEvent>() {  
         @Override  
         public void handle(KeyEvent event) {  
            // Playing the animation  
            rotateTransition.play();  
         }            
      };               
      // Adding an event handler to the text feld  
      textField.addEventHandler(KeyEvent.KEY_TYPED, eventHandlerTextField);  
      // Handling the mouse clicked event(on box)  
      EventHandler<javafx.scene.input.MouseEvent> eventHandlerBox =  
         new EventHandler<javafx.scene.input.MouseEvent>() {  
         @Override  
         public void handle(javafx.scene.input.MouseEvent e) {  
            rotateTransition.stop();   
         }  
      };  
      // Adding the event handler to the box   
      box.addEventHandler(javafx.scene.input.MouseEvent.MOUSE_CLICKED, eventHandlerBox); 
      // Creating a Group object 
      Group root = new Group(box, textField, text);  
      // Creating a scene object  
      Scene scene = new Scene(root, 600, 300);       
      // Setting camera  
      PerspectiveCamera camera = new PerspectiveCamera(false);  
      camera.setTranslateX(0);  
      camera.setTranslateY(0);  
      camera.setTranslateZ(0);  
      scene.setCamera(camera);   
      // Setting title to the Stage
      stage.setTitle("Event Handlers Example");  
      // Adding scene to the stage  
      stage.setScene(scene);  
      // Displaying the contents of the stage  
      stage.show();  
   }  
   // Implementing the interface method 
   public void animation() {  
      launch();  
   }  
}

服务器程序

RMI服务器程序应实现远程接口或扩展实现类。在这里，我们应该创建一个远程对象并将其绑定到RMIregistry 。

以下是此应用程序的服务器程序。在这里，我们将扩展上面创建的类，创建一个远程对象，并使用绑定名称hello将其注册到RMI注册表。

import java.rmi.registry.Registry; 
import java.rmi.registry.LocateRegistry; 
import java.rmi.RemoteException; 
import java.rmi.server.UnicastRemoteObject; 
public class Server extends FxSample { 
   public Server() {} 
   public static void main(String args[]) { 
      try { 
         // Instantiating the implementation class 
         FxSample obj = new FxSample();
         // Exporting the object of implementation class  
         // (here we are exporting the remote object to the stub) 
         Hello stub = (Hello) UnicastRemoteObject.exportObject(obj, 0);  
         // Binding the remote object (stub) in the registry 
         Registry registry = LocateRegistry.getRegistry(); 
         registry.bind("Hello", stub);  
         System.err.println("Server ready"); 
      } catch (Exception e) { 
         System.err.println("Server exception: " + e.toString()); 
         e.printStackTrace(); 
      } 
   } 
}

客户计划

以下是此应用程序的客户端程序。在这里，我们获取远程对象并调用其名为animation()方法。

import java.rmi.registry.LocateRegistry; 
import java.rmi.registry.Registry;  
public class Client { 
   private Client() {} 
   public static void main(String[] args) {  
      try { 
         // Getting the registry 
         Registry registry = LocateRegistry.getRegistry(null); 
         // Looking up the registry for the remote object 
         Hello stub = (Hello) registry.lookup("Hello"); 
         // Calling the remote method using the obtained object 
         stub.animation(); 
         System.out.println("Remote method invoked"); 
      } catch (Exception e) {
         System.err.println("Client exception: " + e.toString()); 
         e.printStackTrace(); 
      } 
   } 
}