outofpaperpolicyimpl.java

高级java2 大学教程(含源码,经典的Java学习教程

// OutofPaperPolicyImpl.java 
// Handles events generated by printer by registering 
// as a responsible listener 
package com.deitel.advjhtp1.jiro.DynamicService.policy;

// Java core packages
import java.io.Serializable;
import java.rmi.*;
import java.util.*;

// Java standard extensions
import javax.swing.*;

// Jini core packages
import net.jini.core.event.*;
import net.jini.core.entry.*;
import net.jini.core.lease.*;

// Jini extension packages
import net.jini.lease.LeaseRenewalManager;
import net.jini.lookup.entry.*;

// Jiro packages
import javax.fma.services.ServiceFinder;
import javax.fma.services.event.*;
import javax.fma.services.log.*;
import javax.fma.util.*;
import javax.fma.common.*;
import javax.fma.server.*;

// Deitel packages
import com.deitel.advjhtp1.jiro.DynamicService.service.*;
import com.deitel.advjhtp1.jiro.DynamicService.common.*;

public class OutofPaperPolicyImpl
   implements OutofPaperPolicy {
    
   private Lease listenerLease;
   private LeaseRenewalManager leaseRenewalManager;

   private LogService logService;
   private PrinterEventListener listener;
   private PrinterManagement printerManagementProxy;
  
   // OutofPaperPolicyImpl constructor
   public OutofPaperPolicyImpl() 
   {
      // subscribe as an responsible listener to certain event
      listener = new PrinterEventListener( this );
         
      // start the OutofPaper management policy
      try {

         // obtain referrence to dynamic service entry point
         printerManagementProxy = getPrinterManagementProxy();

         // obtain referrence to log service
         logService = ServiceFinder.getLogService();

         // obtain referrence to log service
         EventService eventService = 
            ServiceFinder.getEventService();

         // subscribe as responsible listener
         listenerLease = 
            eventService.subscribeResponsibleBefore( 
               ".Printer.Error.OutofPaper", null, listener, 
               "OutofPaperEventListener", null, Lease.FOREVER );

         // renew lease indefinitely
         leaseRenewalManager = new LeaseRenewalManager(
            listenerLease, Lease.FOREVER, null );
         
      } // end try
        
      // handle exception starting policy
      catch ( Exception exception ) {
         System.out.println( "OutofPaperPolicyImpl: " +
            "Exception occurred when starting policy." );
         System.out.println( "Please read debug file ... \n" );
         Debug.debugException( 
            "starting LowTonerPolicy", exception );
      }
                 
      System.out.println( "OutofPaperPolicyImpl: started." ); 

   } // end OutofPaperPolicyImpl constructor

   // stop OutofPaperPolicyImpl
   public void stopPolicy()
   {
      // stopping OutofPaper management policy
      try {
         
         // expire lease
         leaseRenewalManager.cancel( listenerLease );
         System.out.println( "OutofPaperPolicyImpl: stopping." );
      }

      // handle exception canceling lease
      catch ( Exception exception ) {
         System.out.println(  "OutofPaperPolicyImpl: " +
            "Exception occurred when canceling lease." );
         System.out.println( "Please read debug file ... \n" );
         Debug.debugException( 
            "stopping OutofPaper policy", exception );
      }
    }

   // receive notification calls
   public void notify( RemoteEvent remoteEvent ) 
      throws UnknownEventException, RemoteException, 
      EventNotHandledException
   {
      Object sourceObject = null;

      // event source
      try {
          
         // get event source
         sourceObject = remoteEvent.getSource();
      } 
      
      // handle exception getting event source
      catch ( Exception exception ) {
         System.out.println(  "OutofPaperPolicyImpl: " +
            "Exception occurred when getting event source." );
         System.out.println( "Please read debug file ... \n" );
         Debug.debugException( 
            "getting event source", exception );
      }

      // definitely not from our printer
      if ( !( sourceObject instanceof String ) ) {

         throw new EventNotHandledException();
      }
      
      // obtain String value
      String source = ( String ) sourceObject;
      
      // verify origin of event
      if ( source.equals( "com.deitel.advjhtp1.jiro."
         + "DynamicService.printer.ErrorMessage=OutofPaper") ) {
         
         System.out.println( "OutfPaperPolicy: "
            + "handling OutofPaperEvent..." );   
         
         // take action
         try {

            // replenish paper tray
            printerManagementProxy.addPaper( 50 );
      
            // generate the log message parameters
            Serializable params[] = new Serializable[ 2 ];
            params[ 0 ] = source;
            params[ 1 ] = new Date();

            // generate localizable message
            LocalizableMessage localizableMessage = 
               new LocalizableMessage( 
                  OutofPaperPolicyImpl.class, 
                  "Action", params, Locale.US );

            // generate log message
            LogMessage logMessage = new LogMessage(
               localizableMessage, LogMessage.TRACE 
               + ".OutofPaperEvent." + source, null );

            // log action message
            logService.log( logMessage );

         } // end try

         // handle exception posting log message
         catch ( Exception exception ) {
            System.out.println(  "OutofPaperPolicyImpl: " +
               "Exception occurred when posting log message." );
            System.out.println( "Please read debug file ...\n" );
            Debug.debugException( "log service", exception );
         }

      } // end if

      // not event from our printer
      else {
      
         System.out.println( "OutfPaperPolicy: " +
            " NOT handling OutofPaperEvent..." );
         
         // responsible listener requirement 
         // when not handling event.
         throw new EventNotHandledException();
      }

   } // end method notify

   // get dynamic services proxies
   public PrinterManagement getPrinterManagementProxy()
   {
      Entry[] entries = new Entry[] {
         new ServiceInfo( "PrinterManagementImpl", 
            "Deitel Association, Inc.",
            "Deitel Association, Inc",
            "1.0", "Model 0", "0.0.0.1" )
      };

      String domain = System.getProperty( "javax.fma.domain" );
      DynamicServiceFinder finder = 
         new DynamicServiceFinder( domain, entries );

      // return proxy
      return ( PrinterManagement ) finder.getService();

   } // end method getPrinterManagementProxy

   // defines class as dynamic service during deployment
   private Entry[] getLookupEntries()
   {
      return ( new Entry[] {
         new ServiceInfo( "OutofPaperPolicyImpl", 
            "Deitel Association, Inc.",
            "Deitel Association, Inc",
            "1.0", "Model 0", "0.0.0.1" )
         } 
      ); 
   } 
} 

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