Bank.java

package org.prevayler.demos.demo2.business;
import java.util.*;

public class Bank implements java.io.Serializable {
  private static final long serialVersionUID=9202866398345361997L;
  private long nextAccountNumber=1;
  private Map accountsByNumber=new HashMap();
  private transient BankListener bankListener;
  public Account createAccount(  String holder) throws Account.InvalidHolder {
    Account account=new Account(nextAccountNumber,holder);
    accountsByNumber.put(new Long(nextAccountNumber++),account);
    if (bankListener != null)     bankListener.accountCreated(account);
    return account;
  }
  public void deleteAccount(  long number) throws AccountNotFound {
    Account account=findAccount(number);
    accountsByNumber.remove(new Long(number));
    if (bankListener != null)     bankListener.accountDeleted(account);
  }
  public List accounts(){
    List accounts=new ArrayList(accountsByNumber.values());
    Collections.sort(accounts,new Comparator(){
      public int compare(      Object acc1,      Object acc2){
        return ((Account)acc1).number() < ((Account)acc2).number() ? -1 : 1;
      }
    }
);
    return accounts;
  }
  public void setBankListener(  BankListener bankListener){
    this.bankListener=bankListener;
  }
  public Account findAccount(  long number) throws AccountNotFound {
    Account account=searchAccount(number);
    if (account == null)     throw new AccountNotFound(number);
    return account;
  }
  public void transfer(  long sourceNumber,  long destinationNumber,  long amount,  Date timestamp) throws AccountNotFound, Account.InvalidAmount {
    Account source=findAccount(sourceNumber);
    Account destination=findAccount(destinationNumber);
    source.withdraw(amount,timestamp);
    if (amount == 666)     throw new RuntimeException("Runtime Exception simulated for rollback demonstration purposes.");
    destination.deposit(amount,timestamp);
  }
  private Account searchAccount(  long number){
    return (Account)accountsByNumber.get(new Long(number));
  }
public class AccountNotFound extends Exception {
    private static final long serialVersionUID=5107181766636463559L;
    AccountNotFound(    long number){
      super("Account not found: " + Account.numberString(number) + ".\nMight have been deleted.");
    }
  }
}