Initial commit (v2)

bin/1. rmireg.bat

@@ -0,0 +1 @@
+start rmiregistry

bin/2. compile.bat

@@ -0,0 +1,3 @@
+set CLASSPATH=%CLASSPATH%;C:\JGroups\jgroups-3.6.0.Final.jar;
+javac -Xlint:unchecked *.java
+pause

bin/3. startServer.bat

@@ -0,0 +1,3 @@
+set CLASSPATH=%CLASSPATH%;C:\JGroups\jgroups-3.6.0.Final.jar;
+java -Djava.net.preferIPv4Stack=true AuctionServer
+pause

bin/4. startClient.bat

@@ -0,0 +1,3 @@
+set /p id="Username (leave blank for new user): "
+java -Djava.net.preferIPv4Stack=true AuctionClient %id%
+pause

bin/rmireg.bat

@@ -1 +0,0 @@
-javac *.java && start rmiregistry

bin/startClient.bat

@@ -1 +0,0 @@
-javac *.java && java AuctionClient

bin/startServer.bat

@@ -1 +0,0 @@
-javac *.java && java AuctionServer

src/Auction.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -31,34 +31,37 @@ import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.X509EncodedKeySpec;
 
 /**
- **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
+ **   @author  Ben Goldsworthy (rumps) <bgoldsworthy96 @ gmail.com>
- **   @version 1.0
+ **   @version 2.0
  **/
 public interface Auction extends java.rmi.Remote {	
-   /**
+   /*
-    **   Creates an auction with the given details, generating a new ID for 
+    *    Methods to validate operations and then remotely invoke methods
-    **   it.
+    *    using JGroups.
-    **   
+    *
-    **   @param desc The auction description.
+    */
-    **   @param owner The auction owner/creator.
-    **   @param startingPrice The auction starting price.
-    **   @param reserve The auction reserve price.
-    **/
-   public void createAuction(String desc, UserWrapper owner, float startingPrice, float reserve) throws java.rmi.RemoteException;
    
    /**
-    **   Removes an auction, provided the user calling the method owns it.
+    **   Invokes the creation of a new auction.
-    **   If the reserve price was met, also returns the winning bidder.
     **   
-    **   @param id The ID of the auction to remove.
+    **   @param newAuction The new auction to create.
-    **   @param currentUser The user calling the method.
-    **   @return The `UserWrapper` of the highest bidder, if applicable.
     **/
-   public UserWrapper removeAuction(int id, UserWrapper currentUser) throws java.rmi.RemoteException;
+   public void openNewAuction(AuctionWrapper newAuction) throws java.rmi.RemoteException;
 
    /**
-    **   Bids on a given auction, provided the bid is more than the
+    **   Validates that the calling user owns the auction in question, and
-    **   current highest price.
+    **   if invokes the closing of the auction, returning the winning
+    **   bidder (if applicaable).
+    **   
+    **   @param id The ID of the auction to bid on.
+    **   @param currentUser The user placing the bid.
+    **   @return The highest bidder, or `null`.
+    **/
+   public void closeAuction(int id, UserWrapper currentUser) throws java.rmi.RemoteException;
+
+   /**
+    **   Validates a bid is higher than the given auctions current price,
+    **   and if so invokes the setting the a new bid and bidder.
     **   
     **   @param id The ID of the auction in question.
     **   @param bidder The user bidding on the auction.
@@ -67,28 +70,33 @@ public interface Auction extends java.rmi.Remote {
    public void bidOnAuction(int id, UserWrapper bidder, float price) throws java.rmi.RemoteException;
    
    /**
-    **   Accessor Method. Retrieves a list of all the auctions.
+    **   Invokes the returning of a list of all the current auctions.
     **   
     **   @return An `ArrayList` of `AuctionWrapper`s.
     **/
-   public ArrayList<AuctionWrapper> getAuctions() throws java.rmi.RemoteException;
+   public ArrayList<AuctionWrapper> showAllAuctions() throws java.rmi.RemoteException;
     
    /**
-    **   Accessor Method. Gets a user, or creates a new one if non 
+    **   Accessor Method. Invokes the retrieval of a preexisting user, 
-    **   exists with the given details.
+    **   if it exists.
     **   
-    **   @param name The user's name.
+    **   @param username The user's username.
-    **   @param email The user's email address.
     **   @return The relevant `UserWrapper`.
     **/
    public UserWrapper getUser(String username) throws java.rmi.RemoteException;   
    
-   public UserWrapper registerUser(String name, String email, String username) throws java.rmi.RemoteException;
+   /**
+    **   Tests that the username entered is not already taken, and
+    **   invokes the creation of a new user with the given details if not.
+    **   
+    **   @param newUser The new user to validate and create.
+    **   @return The newly-created user.
+    **/
+   public UserWrapper registerUser(UserWrapper newUser) throws java.rmi.RemoteException;
    
-   public void close() throws java.rmi.RemoteException;
+   /*
-   
+    *    Methods that are called by the `AuctionClient` program via RMI.
-   public PublicKey getPublicKey() throws java.rmi.RemoteException;
+    */
-   public void sendPublicKey(PublicKey key, String username) throws java.rmi.RemoteException;
     
     /**
     **   Accessor Method. Gets the status resulting from the last action
@@ -98,9 +106,55 @@ public interface Auction extends java.rmi.Remote {
     **/
    public String getStatusofLast() throws java.rmi.RemoteException;
    
+   /**
+    **   Accessor Method. Gets the server's public key.
+    **   
+    **   @return The public key.
+    **/
+   public PublicKey getPublicKey() throws java.rmi.RemoteException;
+   
+   /**
+    **   Retrieves a user's public key and writes it to a file.
+    **   
+    **   @param key The user's public key.
+    **   @param usernam The user's username.
+    **/
+   public void sendPublicKey(PublicKey key, String username) throws java.rmi.RemoteException;
+            
+   /**
+    **   Sends back a user's challenge, signed with the server's private
+    **   key.
+    **   
+    **   @param challenge The user's challenge.
+    **   @return The signature.
+    **/
    public byte[] challengeServer(byte[] challenge) throws java.rmi.RemoteException;
    
+   /**
+    **   Sends a user's a challenge.
+    **   
+    **   @return The challenge.
+    **/
    public byte[] getChallenge() throws java.rmi.RemoteException;
+   
+   /**
+    **   Takes a returned challenge from the user and verifies the
+    **   signature.
+    **   
+    **   @param retChal The returned signature from the user.
+    **   @param username The user's username.
+    **   @return Whether the user has been verified or not.
+    **/
    public boolean returnChallenge(byte[] retChal, String username) throws java.rmi.RemoteException;
+   
+   /**
+    **   Creates a new replica of the server.
+    **/
+   public void replicate() throws java.rmi.RemoteException;
+   
+   /**
+    **   Closes the server and replicas.
+    **/
+   public void close() throws java.rmi.RemoteException;
 }
 

src/AuctionClient.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -37,85 +37,108 @@ import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.X509EncodedKeySpec;
 
 /**
- **   @author  Ben Goldsworthy (rumps) <bgoldsworthy96 @ gmail.com>
+ **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
- **   @version 1.0
+ **   @version 2.0
  **/
 public class AuctionClient {
    // This regex is used to ensure the email address entered is a valid
-   // email address format
+   // RFC 2822 email address format
    // (Source: http://stackoverflow.com/a/153751/4580273)
    private static final Pattern rfc2822 = Pattern.compile("^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$");
+   private static Auction a;
+   private static ArrayList<String> options, debugOptions;
+   private static boolean debugMode;
     
    /**
-    **   Displays the UI.
+    **   Sets up the program and runs the event loop.
     **   
     **   @param args Command-line arguments.
     **/
    public static void main(String[] args) {
-      try {
+      debugMode = true;
+      
+      displayIntro();
+      
       // Create the reference to the remote object through the 
       // remiregistry. This comes first because if it fails we can 
       // skip doing everything else.
-         Auction a = (Auction) Naming.lookup("rmi://localhost/AuctionService");
+      try {
+         a = (Auction) Naming.lookup("rmi://localhost/AuctionService");
          
-         // Declares some variables that'll be used later on.
+         setOptions();
-         Scanner in = new Scanner(System.in);
-         UserWrapper currentUser = null;
-         int id;      
-         float price;
          
          // Authenticates the user, if the program is run with a username
          // as an argument. Otherwise, prompts the user to create a new
          // user.
-         currentUser = login(a, (args.length > 0) ? args[0] : "server");
+         UserWrapper currentUser = login((args.length > 0) ? args[0] : "server");
+      
+         eventLoop(currentUser);
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+   }
+   
+   /*
+    *    Loops indefinitely, taking user input for various options.
+    */
+   private static void eventLoop(UserWrapper currentUser) throws Exception {
+      Scanner in = new Scanner(System.in);
       
       while(true) {         
-            // Resets the variables after each run through.
-            price = 0.0f;
-            
          printOptions();
+         try {
+            int enteredOption = Integer.parseInt(in.nextLine());
+            System.out.println();
             
-            switch(in.nextLine()) {
+            if(enteredOption < options.size()) {
+               switch(options.get(enteredOption)) {
                // This case takes auction details from the user and then
                // creates a new auction with those.
-            case "1":
+               case "Create auction":
-               createNewAuction(a, currentUser);
+                  createNewAuction(currentUser);
                   break;
                // This case removes the auction with the given ID, provided it
                // is owned by the current user.
-            case "2":
+               case "Close auction":
-               deleteAuction(a, currentUser);
+                  closeAuction(currentUser);
                   break;
                // This case displays all the currently-available auctions.
-            case "3":
+               case "View all auctions":
-               displayAuctions(a);
+                  displayAuctions();
                   break;
                // This case places a bid on an auction.
-            case "4":
+               case "Bid on auction":
-               placeBid(a, currentUser);
+                  placeBid(currentUser);
                   break; 
-            // This case exits the program.
+               case "Quit":
-            case "5":
                   System.exit(1);
                   break;
-            // The below cases are remote debug commands.
+               default: break;
-            // This case remotely shuts down the server.
+               }
-            case "6":
+            } else if(debugMode) {
+               switch(debugOptions.get(enteredOption-options.size())) {
+               case "Replicate server":
+                  System.out.println("Server replicating...");
+                  a.replicate();
+                  System.out.println(a.getStatusofLast());
+                  break;
+               case "Close server":
                   a.close();
                   break;
-            default:
+               default: break;
-               break;
                }
             }
-      } catch (Exception e) {
+         } catch (NumberFormatException e) {
-         System.out.println();
+            System.out.println("\nError: That is not a valid option.\n");
-         System.out.println("Exception");
+         }
-         System.out.println(e);
       }
-      System.exit(-1);
    }
    
-   private static UserWrapper login(Auction a, String username) throws java.rmi.RemoteException, java.security.NoSuchAlgorithmException, java.security.InvalidKeyException, java.security.SignatureException {
+   /*
+    *    Logs a user in if they are preexisting (after authentication), or
+    *    prompts a user to create a new user if not.
+    */
+   private static UserWrapper login(String username) throws java.rmi.RemoteException, java.security.NoSuchAlgorithmException, java.security.InvalidKeyException, java.security.SignatureException {
       UserWrapper user = null;
       
       // If the user has run the program with a username argument,
@@ -169,8 +192,8 @@ public class AuctionClient {
             System.out.print("Enter name: ");
             name = in.nextLine();
             
-            System.out.print("Enter email: ");
             while (!rfc2822.matcher(email).matches()) {
+               System.out.print("Enter email: ");
                email = in.nextLine();
                if (!rfc2822.matcher(email).matches()) System.out.println("\nError: invalid email address\n");
             }
@@ -180,8 +203,13 @@ public class AuctionClient {
                username = in.nextLine();
             }
              
-            user = a.registerUser(name, email, username);
+            try {
+               user = a.registerUser(new UserWrapper(name, email, username));
                System.out.println(a.getStatusofLast());
+            } catch (NullPointerException e) {
+               System.out.println(a.getStatusofLast());
+               System.exit(0);
+            }
          }
          
          // Upon a successful user creation, new keys are generated and
@@ -198,12 +226,44 @@ public class AuctionClient {
       return user;
    }
    
+   /*
+    *    Sets the suite of options to present to the user.
+    */
+   private static void setOptions() {
+      options = new ArrayList<String>();
+      options.add("Create auction");
+      options.add("Close auction");
+      options.add("View all auctions");
+      options.add("Bid on auction");
+      options.add("Quit");
+      
+      debugOptions = new ArrayList<String>();
+      debugOptions.add("Replicate server");  
+      debugOptions.add("Close server"); 
+   }
+   
+   /*
+    *    Prints the options for the user.
+    */
    private static void printOptions() {
-      System.out.println("1\tCreate auction\n2\tDelete auction\n3\tView auctions\n4\tBid on auction\n5\tQuit\n6\tClose server");
+      for(String option: options) {
+         System.out.println(options.indexOf(option) +"\t"+option);
+      }
+      if (debugMode) {
+         System.out.println("DEBUG");
+         int num = options.size();
+         for(String option: debugOptions) {
+            System.out.println((num++)+"\t"+option);
+         }
+      }  
       System.out.print("Choose option: "); 
    }
    
-   private static void createNewAuction(Auction a, UserWrapper currentUser) throws java.rmi.RemoteException {
+   /*
+    *    Prompts for auction details and then sends it off to be validated
+    *    and created.
+    */
+   private static void createNewAuction(UserWrapper currentUser) throws java.rmi.RemoteException {
       float startPrice = 0.0f;
       float reservePrice = 0.0f;
       Scanner in = new Scanner(System.in);
@@ -220,38 +280,73 @@ public class AuctionClient {
             reservePrice = Float.parseFloat(in.nextLine());
          }
          
-         a.createAuction(desc, currentUser, startPrice, reservePrice);
+         a.openNewAuction(new AuctionWrapper(0, desc, currentUser, startPrice, reservePrice));
          System.out.println(a.getStatusofLast());
       } catch(NumberFormatException ex){
          System.out.println("\nError: not a valid price\n");
       }   
    }
    
-   private static void deleteAuction(Auction a, UserWrapper currentUser) throws java.rmi.RemoteException {
+   /*
+    *    Closes an auction (after sending the request off for validation).
+    */
+   private static void closeAuction(UserWrapper currentUser) throws java.rmi.RemoteException {
       int id;
       UserWrapper winner;
       Scanner in = new Scanner(System.in);
       
-      if (!a.getAuctions().isEmpty()) {
+      if (!a.showAllAuctions().isEmpty()) {
          System.out.print("Enter auction number: ");
          id = Integer.parseInt(in.nextLine());
          
-         try {
+         a.closeAuction(id, currentUser);
-            winner = a.removeAuction(id, currentUser);
-            System.out.println("\nAuction won by: "+winner.getName()+" <"+winner.getEmail()+">\n");
-         } catch(NullPointerException e) {
          System.out.println(a.getStatusofLast());
-         }
       } else {
          System.out.println("\nNo auctions available\n");
       }
    }
    
-   private static void displayAuctions(Auction a) throws java.rmi.RemoteException {
+   /*
-      if (!a.getAuctions().isEmpty()) {
+    *    Displays the program intro preamble.
+    */
+   private static void displayIntro() {
+      ArrayList<String> lines = new ArrayList<String>();
+      lines.add("");
+      lines.add("AuctionProg 1.0");
+      lines.add("Copyright \u00a9 2016 Ben Goldsworthy (rumps)");
+      lines.add("");
+      lines.add("A program to facilitate a networked auction system");
+      lines.add("This file is part of AuctionProg.");
+      lines.add("");
+      lines.add("AuctionProg is free software: you can redistribute it and/or modify");
+      lines.add("it under the terms of the GNU General Public License as published by");
+      lines.add("the Free Software Foundation, either version 3 of the License, or");
+      lines.add("(at your option) any later version.");
+      lines.add("");
+      lines.add("AuctionProg is distributed in the hope that it will be useful,");
+      lines.add("but WITHOUT ANY WARRANTY; without even the implied warranty of");
+      lines.add("MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the");
+      lines.add("GNU General Public License for more details.");
+      lines.add("");
+      lines.add("You should have received a copy of the GNU General Public License");
+      lines.add("along with AuctionProg.  If not, see <http://www.gnu.org/licenses/>.");
+      lines.add("");
+      
+      for(String line: lines){
+         System.out.println(line);
+      }
+   }
+  
+   /*
+    *    Displays all the available auctions.
+    */
+   private static void displayAuctions() throws java.rmi.RemoteException {
+      if (!a.showAllAuctions().isEmpty()) {
+         System.out.println();
          System.out.println("#\tOwner\tPrice\tDesc");
          for (int i = 0; i < 80; i++) System.out.print("-");
-         for(AuctionWrapper auction: a.getAuctions()){
+         System.out.println();
+         for(AuctionWrapper auction: a.showAllAuctions()){
             System.out.println(auction.getID()+"\t"+auction.getOwner().getUsername()+"\t\u00A3"+String.format("%.2f", auction.getPrice())+"\t"+auction.getDesc());
          }
          System.out.println("");
@@ -260,10 +355,13 @@ public class AuctionClient {
       }
    }
    
-   private static void placeBid(Auction a, UserWrapper currentUser) throws java.rmi.RemoteException {
+   /*
+    *    Takes bid details and sends the bid off.
+    */
+   private static void placeBid(UserWrapper currentUser) throws java.rmi.RemoteException {
       Scanner in = new Scanner(System.in);
       
-      if (!a.getAuctions().isEmpty()) {
+      if (!a.showAllAuctions().isEmpty()) {
          try{
             int id;
             float price;
@@ -284,9 +382,12 @@ public class AuctionClient {
       }   
    }
    
+   /*
+    *    Reads a user's private key from a file.
+    */
    private static PrivateKey readKey(String username) {
       try {
-         FileInputStream keyfis = new FileInputStream(username + "priv.key");
+         FileInputStream keyfis = new FileInputStream("../key/client/"+username + "priv.key");
          byte[] encKey = new byte[keyfis.available()];
          keyfis.read(encKey);
          keyfis.close();
@@ -302,9 +403,12 @@ public class AuctionClient {
          return null;
       }
    }
+   /*
+    *    Reads the server's public key from a file.
+    */
    private static PublicKey readKey() {
       try {
-         FileInputStream keyfis = new FileInputStream("serverpub.key");
+         FileInputStream keyfis = new FileInputStream("../key/client/serverpub.key");
          byte[] encKey = new byte[keyfis.available()];
          keyfis.read(encKey);
          keyfis.close();   
@@ -321,16 +425,25 @@ public class AuctionClient {
       }
    }
    
+   /*
+    *    Writes a private key to a file.
+    */
    private static void writeKey(PrivateKey pKey, String username) {
       wK(pKey, username, "priv");
    }
+   /*
+    *    Writes a public key to a file.
+    */
    private static void writeKey(PublicKey pKey, String username) {
       wK(pKey, username, "pub");
    }
+   /*
+    *    Actually writes a key to a file.
+    */
    private static void wK(Key pKey, String username, String type) {
       try {
          byte[] key = pKey.getEncoded();
-         FileOutputStream keyfos = new FileOutputStream(username+type+".key");
+         FileOutputStream keyfos = new FileOutputStream("../key/client/"+username+type+".key");
          keyfos.write(key);
          keyfos.close();
       } catch (Exception e) {

src/AuctionImpl.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -29,20 +29,31 @@ import java.util.*;
 import java.security.*;
 import java.security.spec.PKCS8EncodedKeySpec;
 import java.security.spec.X509EncodedKeySpec;
+import org.jgroups.JChannel;
+import org.jgroups.blocks.RpcDispatcher;
+import org.jgroups.blocks.RequestOptions;
+import org.jgroups.blocks.ResponseMode;
+import org.jgroups.View;
+import org.jgroups.util.*;
+import java.lang.reflect.InvocationTargetException;
 
 /**
  **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
- **   @version 1.0
+ **   @version 2.0
  **/
 public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements Auction {
    private ArrayList<AuctionWrapper> auctions;
    private ArrayList<UserWrapper> users;
    String status;
    byte[] challenge = new byte[1024];
+   static JChannel channel;
+   static RpcDispatcher disp;
+   static RequestOptions opts = new RequestOptions(ResponseMode.GET_ALL, 5000);
    
    /**   
     **   Constructor Method. Required to declare the `RemoteException`
-    **   instance.
+    **   instance. Also sets up three replicas and creates a test suite of
+    **   three auctions.
     **/
    public AuctionImpl() throws java.rmi.RemoteException {
       super();
@@ -54,9 +65,32 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       status = "";
       generateKeys();
       
-      System.out.println("Server start successful.");
+      System.out.println("Server initiliasation successful.");
+      
+      try {
+         channel=new JChannel();
+         disp = new RpcDispatcher(channel, this);
+         channel.connect("AuctionProg");
+         
+         System.out.println("Creating replicas...");
+         new Replica().start();
+         new Replica().start();
+         new Replica().start();
+         System.out.println("Replicas created.");
+         
+         UserWrapper testUser = new UserWrapper("Test", "test@test.com", "test");
+         this.openNewAuction(new AuctionWrapper(1, "test1", testUser, 12.0f, 14.0f));
+         this.openNewAuction(new AuctionWrapper(2, "test2", testUser, 12.0f, 14.0f));
+         this.openNewAuction(new AuctionWrapper(3, "test3", testUser, 12.0f, 14.0f));
+      } catch (Exception e) {
+         System.out.println(e);
+      }
    }
    
+   /*
+    *    Generates the pair of keys for the server's authentication and
+    *    writes them to files.
+    */
    private void generateKeys() {
       try {
          KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA");
@@ -73,108 +107,226 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /*
+    *    Methods to validate operations and then remotely invoke methods
+    *    using JGroups.
+    *
+    */
+   
    /**
-    **   Creates an auction with the given details, generating a new ID for 
+    **   Invokes the creation of a new auction.
-    **   it.
     **   
-    **   @param desc The auction description.
+    **   @param newAuction The new auction to create.
-    **   @param owner The auction owner/creator.
-    **   @param startingPrice The auction starting price.
-    **   @param reserve The auction reserve price.
     **/
-   public void createAuction(String desc, UserWrapper owner, float startingPrice, float reserve) throws java.rmi.RemoteException {
+   public void openNewAuction(AuctionWrapper newAuction) throws java.rmi.RemoteException {
-      int id = 0;
+      System.out.println("Opening new auction...");
-      String preamble = "Create new auction: ";
+      try {
-      
+         disp.callRemoteMethods(null, "createAuction", new Object[]{newAuction}, new Class[]{AuctionWrapper.class}, opts);
-      lines();
+         status = "Auction successfully opened.";
-      System.out.println(preamble + "begin.");
+         System.out.println("Auction successfully opened.");
-      
+         return;
-      // Gives the new auction the lowest unclaimed ID.
+      } catch (Exception e) {
-      for(AuctionWrapper item: auctions){
+         System.out.println(e);
-         if (id <= item.getID()) {
-            id = item.getID();
       }
-      }
+         status = "Auction could not be opened.";
-      
+      System.out.println("Auction unsuccessfully opened.");
-      auctions.add(new AuctionWrapper(++id, desc, owner, startingPrice, reserve));
-      System.out.println(preamble + "auction "+id+" successfully created.");
-      status = "Auction no. "+id+" successfully created.";
-      
-      System.out.println(preamble + "end.");
-      lines();
    }
    
    /**
-    **   Removes an auction, provided the user calling the method owns it.
+    **   Validates that the calling user owns the auction in question, and
-    **   If the reserve price was met, also returns the winning bidder.
+    **   if invokes the closing of the auction, returning the winning
+    **   bidder (if applicaable).
     **   
-    **   @param id The ID of the auction to remove.
+    **   @param id The ID of the auction to bid on.
-    **   @param currentUser The user calling the method.
+    **   @param currentUser The user placing the bid.
-    **   @return The `UserWrapper` of the highest bidder, if applicable.
+    **   @return The highest bidder, or `null`.
     **/
-   public UserWrapper removeAuction(int id, UserWrapper currentUser) throws java.rmi.RemoteException {
+   public void closeAuction(int id, UserWrapper currentUser) throws java.rmi.RemoteException {
+      System.out.println("Closing auction #"+id+"...");
       AuctionWrapper auction = this.getAuction(id);
       UserWrapper response = null;
-      String preamble = "Close auction "+id+": ";
-      
-      lines();
-      System.out.println(preamble + "begin.");
       
       if (auction.getOwner().getUsername().equals(currentUser.getUsername())) {
-         System.out.println(preamble + "ownership rights confirmed.");
+         System.out.println("Ownership rights confirmed.");
-         auctions.remove(auction);
+         try {
-         System.out.println(preamble + "auction successfully closed.");
+            RspList rsp_list = disp.callRemoteMethods(null, "removeAuction", new Object[]{auction}, new Class[]{AuctionWrapper.class}, opts);
-         status = "Auction no. "+id+" successfully removed";
+            System.out.println("Auction successfully closed.");
-         if (auction.getPrice() >= auction.getReserve()) {
-            System.out.println(preamble + "auction closed with winner.");
-            status = "Auction closed - winner";
-            response = auction.getHighestBidder();
-         } else {
-            System.out.println(preamble + "auction closed with no winner.");
-            status = "Auction closed - no winner";
-         }
-      } else {     
-         System.out.println(preamble + "invalid ownership rights.");
-         status = "Auction no. "+id+" could not be removed - you do not own this auction";
-      }
             
-      System.out.println(preamble + "end.");
+            response = (UserWrapper)rsp_list.getFirst();
-      lines();
+            if (response.getUsername().equals("server")) {
-      return response;
+               status = "Auction closed with no winner";
+            } else {
+               status = "Auction won by: "+response.getName()+" <"+response.getEmail()+">";
+            }
+            return;
+         } catch (Exception e) {
+            System.out.println(e);
+         }
+      }
+      status = "You do not own this auction.";
+      System.out.println("Auction closing unsuccessful.");
    }
    
    /**
-    **   Bids on a given auction, provided the bid is more than the
+    **   Validates a bid is higher than the given auctions current price,
-    **   current highest price.
+    **   and if so invokes the setting the a new bid and bidder.
     **   
     **   @param id The ID of the auction in question.
     **   @param bidder The user bidding on the auction.
     **   @param price The amount bid.
     **/
-   public void bidOnAuction(int id, UserWrapper bidder, float price) 
+   public void bidOnAuction(int id, UserWrapper bidder, float price) throws java.rmi.RemoteException {
-      throws java.rmi.RemoteException {
       AuctionWrapper auction;
-      String preamble = "Bid on auction "+id+": ";
+      System.out.println("Placing bid on auction #"+id+"...");
-      
-      lines();
-      System.out.println(preamble + "begin.");
       
+      try {
          if ((auction = this.getAuction(id)) != null) {
             if (price > auction.getPrice()) {
-            this.getAuction(id).setBid(bidder, price);
+               disp.callRemoteMethods(null, "setBid", new Object[]{auction, bidder, price}, new Class[]{AuctionWrapper.class, UserWrapper.class, float.class}, opts);
-            System.out.println(preamble + "bid successful.");
+               System.out.println("Bid successful.");
                status = "Bid successful";
             } else {
-            System.out.println(preamble + "bid less than current highest bid.");
+               System.out.println("Bid unsuccessful.");
                status = "Price less than highest bid";
             }
          } else {
-         System.out.println(preamble + "auction ID not found.");
+            System.out.println("Bid unsuccessful.");
             status = "Invalid auction ID";
          }
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+   }
    
-      System.out.println(preamble + "end.");
+   /**
-      lines();
+    **   Invokes the returning of a list of all the current auctions.
+    **   
+    **   @return An `ArrayList` of `AuctionWrapper`s.
+    **/
+   public ArrayList<AuctionWrapper> showAllAuctions() throws java.rmi.RemoteException {
+      try {
+         RspList rsp_list=disp.callRemoteMethods(null, "getAllAuctions", null, null, opts);
+         return (ArrayList<AuctionWrapper>)rsp_list.getFirst();
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+      return null;
+   }   
+     
+   /**
+    **   Accessor Method. Invokes the retrieval of a preexisting user, 
+    **   if it exists.
+    **   
+    **   @param username The user's username.
+    **   @return The relevant `UserWrapper`.
+    **/
+   public UserWrapper getUser(String username) throws java.rmi.RemoteException {
+      try {
+         RspList rsp_list=disp.callRemoteMethods(null, "getAllUsers", null, null, opts);
+         for(UserWrapper user: (ArrayList<UserWrapper>)rsp_list.getFirst()) {
+            if (user.getUsername().equals(username)) {
+               status = "Welcome back, "+user.getName()+".";
+               return user;
+            }
+         }
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+      status = "No such user.";
+      return null;
+   }
+   
+   /**
+    **   Tests that the username entered is not already taken, and
+    **   invokes the creation of a new user with the given details if not.
+    **   
+    **   @param newUser The new user to validate and create.
+    **   @return The newly-created user.
+    **/
+   public UserWrapper registerUser(UserWrapper newUser) throws java.rmi.RemoteException {
+      try {
+         RspList rsp_list=disp.callRemoteMethods(null, "getAllUsers", null, null, opts);
+
+         if (!rsp_list.isEmpty()) {
+            for(UserWrapper user: (ArrayList<UserWrapper>)rsp_list.getFirst()){
+               if (user.getUsername().equals(newUser.getUsername())) {
+                  status = "Username taken. Either choose a new username or, if trying to login to an existing account, rerun the program as 'AuctionClient <username>'.";
+                  return null;
+               }
+            }
+         }
+         
+         disp.callRemoteMethods(null, "createUser", new Object[]{newUser}, new Class[]{UserWrapper.class}, opts);
+         status = "New user created. Hello "+newUser.getName()+".";
+         return newUser;    
+      } catch (Exception e) {
+         System.out.println(e);
+      }   
+      status = "Something went wrong";
+      return null;
+   }
+   
+   /*
+    *    Methods that are remotely invoked via RPC on both this and the
+    *    `Replica`s due to multicasting.
+    */
+    
+   /**
+    **   Creates an auction with the given details.
+    **   
+    **   @param newAuction An `AuctionWrapper` of the new auction.
+    **/
+   private void createAuction(AuctionWrapper newAuction) throws java.rmi.RemoteException {
+      int id = 0;
+      
+      // Gives the new auction the lowest unclaimed ID.
+      for(AuctionWrapper auction: auctions){
+         if (id <= auction.getID()) {
+            id = auction.getID();
+         }
+      }
+      
+      newAuction.setID(++id);
+      auctions.add(newAuction);
+      status = "Auction no. "+id+" successfully created.";
+   }
+   
+   /**
+    **   Removes an auction. If the reserve price was met, also returns 
+    **   the winning bidder, otherwise an indicative `UserWrapper` with
+    **   username of "server".
+    **   
+    **   @param auction The `AuctionWrapper` of the auction to remove.
+    **   @return The `UserWrapper` of the highest bidder, or `null`.
+    **/
+   private UserWrapper removeAuction(AuctionWrapper auction) throws java.rmi.RemoteException {
+      auctions.remove(auction);
+      
+      if (auction.getPrice() >= auction.getReserve()) {
+         return auction.getHighestBidder();
+      } else {
+         return new UserWrapper("err", "err", "server");
+      }
+   }
+   
+   /**
+    **   Mutator Method. Sets the bid on an auction.
+    **   
+    **   @param auction The `AuctionWrapper` of the auction to bid on.
+    **   @param user The user bidding on the auction.
+    **   @param price The amount the user has bid.
+    **/
+   private void setBid(AuctionWrapper auction, UserWrapper user, float price) {
+      this.getAuction(auction.getID()).setBid(user, price);
+   }
+   
+   /**
+    **   Accessor Method. Retrieves a list of all the auctions.
+    **   
+    **   @return An `ArrayList` of `AuctionWrapper`s.
+    **/
+   private ArrayList<AuctionWrapper> getAllAuctions() {
+      return this.auctions;
    }
    
    /**
@@ -184,55 +336,41 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
     **   @return The `AuctionWrapper` indicated.
     **/
    private AuctionWrapper getAuction(int id) {
-      for(AuctionWrapper auction: auctions){
+      try {
+         RspList rsp_list=disp.callRemoteMethods(null, "getAllAuctions", null, null, opts);
+         for(AuctionWrapper auction: (ArrayList<AuctionWrapper>)rsp_list.getFirst()) {
             if (auction.getID() == id) {
                return auction;
             }
          }
+      } catch (Exception e) {
+         System.out.println(e);
+      }
       return null;
    }
    
    /**
-    **   Accessor Method. Retrieves a list of all the auctions.
+    **   Creates a new user.
     **
-    **   @return An `ArrayList` of `AuctionWrapper`s.
+    **   @param newUser The new user to create.
     **/
-   public ArrayList<AuctionWrapper> getAuctions() throws java.rmi.RemoteException {
+   private void createUser(UserWrapper newUser) {
-      return auctions;
+      System.out.println("doing it");
+      this.users.add(newUser);
    }
   
    /**
-    **   Accessor Method. Gets a user, or creates a new one if non 
+    **   Gets the list of all users.
-    **   exists with the given details.
     **
-    **   @param name The user's name.
+    **   @return An `ArrayList` of users.
-    **   @param email The user's email address.
-    **   @return The relevant `UserWrapper`.
     **/
-   public UserWrapper getUser(String username) throws java.rmi.RemoteException {
+   private ArrayList<UserWrapper> getAllUsers() {
-      for(UserWrapper user: users){
+      return this.users;
-         if (user.getUsername().equals(username)) {
-            status = "Welcome back, "+user.getName()+".";
-            return user;
-         }
-      }
-      status = "No such user.";
-      return null;
    }
    
-   public UserWrapper registerUser(String name, String email, String username) throws java.rmi.RemoteException {
+   /*
-      for(UserWrapper user: users){
+    *    Methods that are called by the `AuctionClient` program via RMI.
-         if (user.getUsername().equals(username)) {
+    */
-            status = "Username taken. Either choose a new username or, if trying to login to an existing account, rerun the program as 'AuctionClient <username>'.";
-            return null;
-         }
-      }
-      
-      UserWrapper user = new UserWrapper(name, email, username);
-      users.add(user);
-      status = "New user created. Hello "+name+".";
-      return user;
-   }
     
    /**
     **   Accessor Method. Gets the status resulting from the last action
@@ -244,18 +382,34 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       return "\n"+status+"\n";
    }
    
+   /**
+    **   Accessor Method. Gets the server's public key.
+    **   
+    **   @return The public key.
+    **/
    public PublicKey getPublicKey() throws java.rmi.RemoteException {
       return this.readKey("server");
    }
    
+   /**
+    **   Retrieves a user's public key and writes it to a file.
+    **   
+    **   @param key The user's public key.
+    **   @param usernam The user's username.
+    **/
    public void sendPublicKey(PublicKey key, String username) throws java.rmi.RemoteException {
       this.writeKey(key, username);
    }
    
+   /*
+    *    Writes the server's private key to a file.
+    *   
+    *    @param The private key.
+    */
    private static void writeKey(PrivateKey pKey) throws java.rmi.RemoteException {
       try {
          byte[] key = pKey.getEncoded();
-         FileOutputStream keyfos = new FileOutputStream("../key/serverpriv.key");
+         FileOutputStream keyfos = new FileOutputStream("../key/server/serverpriv.key");
          keyfos.write(key);
          keyfos.close();
       } catch (Exception e) {
@@ -265,10 +419,15 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /*
+    *    Writes the server's public key to a file.
+    *   
+    *    @param The public key.
+    */
    private static void writeKey(PublicKey pKey) throws java.rmi.RemoteException {
       try {
          byte[] key = pKey.getEncoded();
-         FileOutputStream keyfos = new FileOutputStream("../key/serverpub.key");
+         FileOutputStream keyfos = new FileOutputStream("../key/server/serverpub.key");
          keyfos.write(key);
          keyfos.close();
       } catch (Exception e) {
@@ -278,10 +437,15 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /*
+    *    Writes a user's public key to a file.
+    *   
+    *    @param The public key.
+    */
    private static void writeKey(PublicKey pKey, String username) throws java.rmi.RemoteException {
       try {
          byte[] key = pKey.getEncoded();
-         FileOutputStream keyfos = new FileOutputStream("../key/"+username+"pub.key");
+         FileOutputStream keyfos = new FileOutputStream("../key/server/"+username+"pub.key");
          keyfos.write(key);
          keyfos.close();
       } catch (Exception e) {
@@ -291,9 +455,14 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /*
+    *    Reads the server's private key from a file.
+    *   
+    *    @return The private key.
+    */
    private static PrivateKey readKey() throws java.rmi.RemoteException {
       try {
-         FileInputStream keyfis = new FileInputStream("../key/serverpriv.key");
+         FileInputStream keyfis = new FileInputStream("../key/server/serverpriv.key");
          byte[] encKey = new byte[keyfis.available()];
          keyfis.read(encKey);
          keyfis.close();
@@ -310,9 +479,15 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /*
+    *    Reads a user's public key from a file.
+    *   
+    *    @param username The user's username.
+    *    @return The public key.
+    */
    private static PublicKey readKey(String username) throws java.rmi.RemoteException {
       try {
-         FileInputStream keyfis = new FileInputStream("../key/"+username+"pub.key");
+         FileInputStream keyfis = new FileInputStream("../key/server/"+username+"pub.key");
          byte[] encKey = new byte[keyfis.available()];  
          keyfis.read(encKey);
 
@@ -330,7 +505,13 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
 
-   
+   /**
+    **   Sends back a user's challenge, signed with the server's private
+    **   key.
+    **   
+    **   @param challenge The user's challenge.
+    **   @return The signature.
+    **/
    public byte[] challengeServer(byte[] challenge) throws java.rmi.RemoteException {   
       try {
          Signature dsa = Signature.getInstance("SHA1withDSA"); 
@@ -347,17 +528,32 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
       }
    }
    
+   /**
+    **   Sends a user's a challenge.
+    **   
+    **   @return The challenge.
+    **/
    public byte[] getChallenge() throws java.rmi.RemoteException {
       challenge = new byte[1024];
       new Random().nextBytes(this.challenge);
       return this.challenge;
    }
    
+   /**
+    **   Takes a returned challenge from the user and verifies the
+    **   signature.
+    **   
+    **   @param retChal The returned signature from the user.
+    **   @param username The user's username.
+    **   @return Whether the user has been verified or not.
+    **/
    public boolean returnChallenge(byte[] retChal, String username) throws java.rmi.RemoteException {
       System.out.println("Authenticating user '"+username+"'...");
-      for(UserWrapper user: users){
+      System.out.println(users);
-         if (user.getUsername().equals(username)) {
       try {
+         RspList rsp_list=disp.callRemoteMethods(null, "getAllUsers", null, null, opts);
+         for(UserWrapper user: (ArrayList<UserWrapper>)rsp_list.getFirst()) {
+            if (user.getUsername().equals(username)) {
                Signature sig = Signature.getInstance("SHA1withDSA");
                sig.initVerify(this.readKey(username));
 
@@ -366,24 +562,41 @@ public class AuctionImpl extends java.rmi.server.UnicastRemoteObject implements
                boolean verifies = sig.verify(retChal);
                System.out.println(username+" signature verifies: " + verifies);
                return verifies;
+            }
+         }
       } catch (Exception e) {
-               System.out.println();
-               System.out.println("Exception");
          System.out.println(e);
       }
-         }
+      
-      }
       System.out.println("User '"+username+"' not found.");
       return false;
    }
    
+   /**
+    **   Creates a new replica of the server.
+    **/
+   public void replicate() throws java.rmi.RemoteException {
+      try {
+         new Replica().start();
+         status = "Server replication successful.";
+      } catch (Exception e) {
+         System.out.println(e);
+         status = "Server replication failed.";
+      }
+   }
+   
+   /**
+    **   Closes the server and replicas.
+    **/
    public void close() throws java.rmi.RemoteException {
+      System.out.println("Stopping replicas");
+      try {
+         disp.callRemoteMethods(null, "stop", null, null, opts);
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+      channel.close();
+      disp.stop();
       System.exit(-1);
    }
-   
-   private void lines() {
-      for (int i = 0; i < 80; i++) System.out.print("-");
-      System.out.print("\n");
 }
-}
-

src/AuctionServer.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -25,16 +25,18 @@
  **/
 
 import java.rmi.Naming;
+import java.util.*;
 
 /**
  **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
- **   @version 1.0
+ **   @version 2.0
  **/
 public class AuctionServer {
    /**   
     **   Constructor Method.
     **/
    public AuctionServer() {
+      
       try {
        	Auction a = new AuctionImpl();
        	Naming.rebind("rmi://localhost/AuctionService", a);
@@ -49,6 +51,39 @@ public class AuctionServer {
     **   @param args Command-line arguments.
     **/
    public static void main(String args[]) {
+      displayIntro();
+      
       new AuctionServer();
    }
+   
+   /*
+    *    Displays the intro preamble to the user.
+    */
+   private static void displayIntro() {
+      ArrayList<String> lines = new ArrayList<String>();
+      lines.add("");
+      lines.add("AuctionProg 1.0");
+      lines.add("Copyright \u00a9 2016 Ben Goldsworthy (rumps)");
+      lines.add("");
+      lines.add("A program to facilitate a networked auction system");
+      lines.add("This file is part of AuctionProg.");
+      lines.add("");
+      lines.add("AuctionProg is free software: you can redistribute it and/or modify");
+      lines.add("it under the terms of the GNU General Public License as published by");
+      lines.add("the Free Software Foundation, either version 3 of the License, or");
+      lines.add("(at your option) any later version.");
+      lines.add("");
+      lines.add("AuctionProg is distributed in the hope that it will be useful,");
+      lines.add("but WITHOUT ANY WARRANTY; without even the implied warranty of");
+      lines.add("MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the");
+      lines.add("GNU General Public License for more details.");
+      lines.add("");
+      lines.add("You should have received a copy of the GNU General Public License");
+      lines.add("along with AuctionProg.  If not, see <http://www.gnu.org/licenses/>.");
+      lines.add("");
+      
+      for(String line: lines){
+         System.out.println(line);
+      }
+   }
 }

src/AuctionWrapper.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -28,7 +28,7 @@ import java.io.*;
 
 /**
  **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
- **   @version 1.0
+ **   @version 2.0
  **/
 public class AuctionWrapper implements Serializable {
    private int id;
@@ -120,4 +120,13 @@ public class AuctionWrapper implements Serializable {
    public float getReserve() {
 		return this.reserve;
 	}
+   
+   
+   /**   
+    **   Mutator Method. Sets the auction ID.
+    **   @param id The new auction ID.
+    **/
+   public void setID(int id) {
+		this.id = id;
+	}
 }

src/GenSig.java

@@ -1,47 +0,0 @@
-import java.io.*;
-import java.security.*;
-
-class GenSig {
-   public static void main(String[] args) {
-      /* Generate a DSA signature */
-
-      if (args.length != 1) {
-         System.out.println("Usage: GenSig nameOfFileToSign");
-      } else try {
-         KeyPairGenerator keyGen = KeyPairGenerator.getInstance("DSA", "SUN");
-         SecureRandom random = SecureRandom.getInstance("SHA1PRNG", "SUN");
-         keyGen.initialize(1024, random);
-         
-         KeyPair pair = keyGen.generateKeyPair();
-         PrivateKey priv = pair.getPrivate();
-         PublicKey pub = pair.getPublic();
-         
-         Signature dsa = Signature.getInstance("SHA1withDSA", "SUN"); 
-         dsa.initSign(priv);
-
-         FileInputStream fis = new FileInputStream(args[0]);
-         BufferedInputStream bufin = new BufferedInputStream(fis);
-         byte[] buffer = new byte[1024];
-         int len;
-         while ((len = bufin.read(buffer)) >= 0) {
-             dsa.update(buffer, 0, len);
-         };
-         bufin.close();
-         
-         byte[] realSig = dsa.sign();
-         
-         /* save the signature in a file */
-         FileOutputStream sigfos = new FileOutputStream("sig");
-         sigfos.write(realSig);
-         sigfos.close();
-         
-         /* save the public key in a file */
-         byte[] key = pub.getEncoded();
-         FileOutputStream keyfos = new FileOutputStream("suepk");
-         keyfos.write(key);
-         keyfos.close();
-      } catch (Exception e) {
-         System.err.println("Caught exception " + e.toString());
-      }
-   }
-}

src/Replica.java

@@ -0,0 +1,158 @@
+/*
+ *                             AuctionProg 2.0                        
+ *                  Copyright © 2016 Ben Goldsworthy (rumps)        
+ *                                                                      
+ * A program to facilitate a networked auction system.             
+ *                                                                           
+ * This file is part of AuctionProg.                                         
+ *                                                                            
+ * AuctionProg is free software: you can redistribute it and/or modify        
+ * it under the terms of the GNU General Public License as published by       
+ * the Free Software Foundation, either version 3 of the License, or          
+ * (at your option) any later version.                                        
+ *                                                                            
+ * AuctionProg is distributed in the hope that it will be useful,             
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of             
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              
+ * GNU General Public License for more details.                               
+ *                                                                            
+ * You should have received a copy of the GNU General Public License          
+ * along with AuctionProg.  If not, see <http://www.gnu.org/licenses/>.       
+ */
+
+/**
+ ** This class represents a User.
+ **/
+
+import java.io.*;
+import java.util.*;
+import org.jgroups.JChannel;
+import org.jgroups.blocks.RpcDispatcher;
+import org.jgroups.blocks.RequestOptions;
+import org.jgroups.blocks.ResponseMode;
+import org.jgroups.util.*;
+
+/**
+ **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
+ **   @version 2.0
+ **/
+public class Replica {
+   JChannel channel;
+   RpcDispatcher disp;
+   RequestOptions opts=new RequestOptions(ResponseMode.GET_ALL, 5000);
+   
+   private ArrayList<AuctionWrapper> auctions;
+   private ArrayList<UserWrapper> users;
+   
+   /**   
+    **   Connects to the channel and sets itself up.
+    **/
+	public void start() {
+      try {
+         channel = new JChannel();
+         disp = new RpcDispatcher(channel, this);
+         channel.connect("AuctionProg");
+         
+         auctions = new ArrayList<AuctionWrapper>();
+         users = new ArrayList<UserWrapper>();
+      } catch (Exception e) {
+         System.out.println(e);
+      }
+	}
+   
+   /**   
+    **   Shuts down the replica.
+    **/
+   public void stop() {
+      channel.close();
+      disp.stop();
+   }
+   
+   /**   
+    **   Creates a new auction.
+    **
+    **   @param newAuction The new auction to create.
+    **/
+   public void createAuction(AuctionWrapper newAuction) {
+      int id = 0;
+      
+      // Gives the new auction the lowest unclaimed ID.
+      for(AuctionWrapper auction: auctions){
+         if (id <= auction.getID()) {
+            id = auction.getID();
+         }
+      }
+      
+      newAuction.setID(++id);
+      auctions.add(newAuction);
+   }
+   
+   /**   
+    **   Removes an auction from the list.
+    **
+    **   @param auction The auction to remove.
+    **   @return The highest-bidding user (if applicable).
+    **/
+   public UserWrapper removeAuction(AuctionWrapper auction) {
+      auctions.remove(auction);
+      
+      if (auction.getPrice() >= auction.getReserve()) {
+         return auction.getHighestBidder();
+      } else {
+         return new UserWrapper("err", "err", "server");
+      }
+   }
+   
+   /**   
+    **   Mutator Method. Sets a new bid on an auction.
+    **  
+    **   @param auction The auction to bid on.
+    **   @param user The user bidding.
+    **   @param price The user's bid.
+    **/
+   public void setBid(AuctionWrapper auction, UserWrapper user, float price) {
+      this.getAuction(auction.getID()).setBid(user, price);
+   }
+   
+   /**   
+    **   Accessor Method. Gets all the auctions.
+    **
+    **   @return The list of auctions.
+    **/
+   public ArrayList<AuctionWrapper> getAllAuctions() {
+      return this.auctions;
+   }
+   
+   /**   
+    **   Gets an auction by ID.
+    **
+    **   @param id The auction ID.
+    **   @return The auction requested, or `null`.
+    **/
+   private AuctionWrapper getAuction(int id) {
+      for(AuctionWrapper auction: auctions) {
+         if (auction.getID() == id) {
+            return auction;
+         }
+      }
+      return null;
+   }
+   
+   /**   
+    **   Accessor Method. Gets the list of all users.
+    **
+    **   @return The list of users.
+    **/
+   public ArrayList<UserWrapper> getAllUsers() {
+      return this.users;
+   }
+   
+   /**    
+    **   Creates a new user.
+    **
+    **   @param The new user to create.
+    **/
+   public void createUser(UserWrapper newUser) {
+      this.users.add(newUser);
+   }   
+}

src/UserWrapper.java

@@ -1,5 +1,5 @@
 /*
- *                             AuctionProg 1.0                        
+ *                             AuctionProg 2.0                        
  *                  Copyright © 2016 Ben Goldsworthy (rumps)        
  *                                                                      
  * A program to facilitate a networked auction system.             
@@ -28,7 +28,7 @@ import java.io.*;
 
 /**
  **   @author  Ben Goldsworthy (rumps) <me+auctionprog@bengoldsworthy.net>
- **   @version 1.0
+ **   @version 2.0
  **/
 public class UserWrapper implements Serializable {
    private String name;
@@ -49,19 +49,23 @@ public class UserWrapper implements Serializable {
    
    /**   
     **   Accessor Method. Returns the user's name.
-    **   @param The user's name.
+    **   @return The user's name.
     **/
 	public String getName() {
 		return this.name;
 	}
    
+   /**   
+    **   Accessor Method. Returns the user's username.
+    **   @return The user's username.
+    **/
 	public String getUsername() {
 		return this.username;
 	}
    
    /**   
     **   Accessor Method. Returns the user's email address.
-    **   @param The user's email address.
+    **   @return The user's email address.
     **/
    public String getEmail() {
 		return this.email;