bankimpl.java

A bank clien/server example implemented by RMI, to perform functions of creatAccount and accessAccou

import java.rmi.RemoteException;
import java.rmi.server.UnicastRemoteObject;
import java.rmi.Naming;
import java.util.*;

/**
 * 
 */

/**
 * @author Kee
 *
 */
public class BankImpl extends UnicastRemoteObject implements Bank {
	
	private Hashtable accounts = new Hashtable();
	private Hashtable openAccounts = new Hashtable();
	private Hashtable lookup = new Hashtable();
	private int nextPin = 0;
	
	BankImpl() throws RemoteException{
	}
	
	/* (non-Javadoc)
	 * @see Bank#createAccount(java.lang.String)
	 */
	@Override
	synchronized public int createAccount(String name) throws RemoteException {
		// TODO Auto-generated method stub
		if (accounts.containsKey(name)){
			return -1;
		}
		else{
			Account account = new Account();
			accounts.put(name, account);
			account.setPin(++nextPin);
			return nextPin;
		}
	}
	
	/* (non-Javadoc)
	 * @see Bank#openAccount(Details)
	 */
	@Override
	synchronized public int openAccount(Details d) throws RemoteException {
		// TODO Auto-generated method stub
		String suppliedName = d.getName();
		if (accounts.containsKey(suppliedName)){
			Account account = (Account)accounts.get(suppliedName);
			int storedPin = account.getPin();
			int suppliedPin = d.getPin();
				if (storedPin == suppliedPin){
					if (openAccounts.containsKey(suppliedPin))
							return -1;
					else{
						int id = storedPin + 1000;
						lookup.put(new Integer(id), suppliedName);
						openAccounts.put(suppliedName, new Integer(id));
						return id;
					}
				}
				else 
					return -1;
		}
		else
			return -1;
	}
	
	/* (non-Javadoc)
	 * @see Bank#incBalance(int, double)
	 */
	@Override
	synchronized public boolean incBalance(int id, double amount) throws RemoteException {
		// TODO Auto-generated method stub
		Integer passedId = new Integer(id);
		if (lookup.contains(passedId)){
			String name = (String)lookup.get(passedId);
			if (accounts.containsKey(name)){
				Account a = (Account)accounts.get(name);
				return a.incBalance(amount);
			}
			else
				return false;
		}
		else
			return false;
	}
	
	/* (non-Javadoc)
	 * @see Bank#decBalance(int, double)
	 */
	@Override
	public boolean decBalance(int id, double amount) throws RemoteException {
		// TODO Auto-generated method stub
		Integer passedId = new Integer(id);
		if (lookup.containsKey(passedId)){
			String name = (String)lookup.get(passedId);
			if (accounts.containsKey(name)){
				Account a = (Account)accounts.get(name);
				if (a.decBalance(amount))
					return true;
				else 
					return false;
			}
			else
				return false;
		}
		return false;
	
	}
	/* (non-Javadoc)
	 * @see Bank#getBalance(int)
	 */
	@Override
	synchronized public double getBalance(int id) throws RemoteException {
		// TODO Auto-generated method stub
		Integer passedId = new Integer(id);
		if (lookup.containsKey(passedId)){
			String name = (String)lookup.get(passedId);
			if (accounts.containsKey(name)){
				Account a = (Account)accounts.get(name);
				return a.getBalance();
			}
			else
				return -1;
		}
		else
			return -1;
	}

	/* (non-Javadoc)
	 * @see Bank#close(int)
	 */
	@Override
	public boolean close(int id) throws RemoteException {
		// TODO Auto-generated method stub
		Integer passedId = new Integer(id);
		if (lookup.containsKey(passedId)){
			String suppliedName = (String)lookup.get(passedId);
			lookup.remove(passedId);
			openAccounts.remove(suppliedName);
			return true;
		}
		else
			return false;
	}
	
	public static void main(String[] args) throws RemoteException{
		String name = "TheBank";
		System.out.println("Registering the bank object...");
		Bank bank = new BankImpl();
		try{
			Naming.rebind(name, bank);
		}
		catch (Exception e){
			System.out.println("Caught exception while registering: " + e);
		}
		System.out.println("Remote bank ready...");
	}


}