网络客户端 Applet 示例

The QuoteClientApplet class allows you to fetch quotations from a server-side application that runs on the same host as this applet. This class also displays the quotation received from the server.

The QuoteServer.java and QuoteServerThread.java classes make up the server-side application that returns quotations. Here's a text file ( one-liners.txt) that contains a number of quotations.

Perform the following steps to test QuoteClientApplet.

1. Download and save the following files to your local machine.
   • QuoteClientApplet
   • QuoteServer.java
   • QuoteServerThread.java
   • one-liners.txt
   • quoteApplet.html
2. Include the following HTML code in a web page to deploy QuoteClientApplet.

   <script src=
     "https://www.java.com/js/deployJava.js"></script>
   <script> 
       var attributes =
         { code:'QuoteClientApplet.class',  width:500, height:100} ; 
       var parameters =
         { codebase_lookup:'true', permissions:'sandbox' };
       deployJava.runApplet(attributes, parameters, '1.6'); 
   </script>
   
   

   Alternatively, you can use the quoteApplet.html page that already contains this HTML code.
3. Compile the QuoteClientApplet.java class. Copy the generated class files to the same directory where you saved your web page.
4. Compile the classes for the server-side application, QuoteServer.java and QuoteServerThread.java.
5. Copy the file one-liners.txt to the directory that has the class files for the server-side application (generated in the previous step).
6. Start the server-side application.

   java QuoteServer
   

   You should see a message with the port number, as shown in the following example. Note the port number.

   QuoteServer listening on port:3862
   

7. Open the web page containing your applet in a browser by entering the URL of the web page. The host name in the URL should be the same as the name of the host on which the server-side application is running.

   For example, if the server-side application is running on a machine named JohnDoeMachine, you should enter a similar URL. The exact port number and path will vary depending on your web server setup.

   http://JohnDoeMachine:8080/quoteApplet/quoteApplet.html
   

   The QuoteClientApplet will be displayed on the web page.
8. Enter the port number of your server-side application in the applet's text field and click OK. A quotation is displayed.

Here is a screen capture of the applet in action.

QuoteServer Sample Output