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Using a proxy template to write a server is a good idea?

For a school project, I need to write a simple Java server that constantly listens on the incoming directory and moves files from this directory to another location. The server needs to log information and error messages, so I decided to use a proxy template for this. So I created the following ServerInterface:

public interface ServerInterface extends Runnable {

    public void initialize(String repPath, ExecutorInterface executor, File propertiesFile) throws ServerInitException;

    public void run();

    public void terminate();

    public void updateHTML();

    public File[] scanIncomingDir();

    public List<DatasetAttributes> moveIncomingFilesIfComplete(File[] incomingFiles);

}

Then I created an implementation Serverrepresenting the real object and a class ProxyServerrepresenting the proxy. It also Serverhas a factory method that creates an object ProxyServer, but returns it as ServerInterface.

The method runin the proxy object is as follows:

@Override
    public void run(){

        log(LogLevels.INFO, "server is running ...");

        while( !stopped ){

            try {

                File[] incomingContent = scanIncomingDir();
                moveIncomingFilesIfComplete(incomingContent);
                updateHTML();
                pause();

            } catch (Exception e) {
                logger.logException(e, new Timestamp(timestampProvider.getTimestamp()));
                pause();
            }

        }

        log(LogLevels.INFO, "server stopped");
    }

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Before delegation, the proxy first registers the launch. After delegation, the proxy registers a shutdown:

// Snapshot from what should look like the run method implementation
// in your proxy.

public ServerInterfaceProxy(ServerInterface target){
    this.proxiedTarget = target;
}

public void run(){
    log(LogLevels.INFO, "server is running ...");
    this.proxiedTarget.run();
    log(LogLevels.INFO, "server is running ...");
}

This implementation can also be understood as an implementation of the Decorator template. IMHO, I believe that to some extent (when it comes to implementation), Proxy and Decorator are equivalent: like target interception / capture behavior.

0
source

Take a look at the Java 7 WatchService class.

Using proxy behavior for this is almost certainly crowded.

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source

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