////////// Methods written for remote login and logout:
// activates a login from a remote site to account #id and returns only the account's balance
// (and not the account itself). If id is nonexistant/in use, returns -1
public object loginRemote(string id)
{
int ans = -1;
IAcct a = this.login(id);
if (a != null)
{
ans = a.getBalance();
}
return(ans);
}
// terminates the use of the opened acct; returns string that states outcome
public string handleLogout()
{
string ans = "error";
if (acct != null)
{
database.logout(accountId);
acct = null; accountId = null;
ans = "logged out";
}
return(ans);
}
// opens acct# accountID for access; returns outcome as a string to display
public string handleLogin(string accountId)
{
string ans = accountId + " error";
if (acct == null)
{ // no account open at this moment?
acct = database.login(accountId);
if (acct != null)
{ // did accountID open ok ?
this.accountId = accountId;
ans = accountId + " opened OK";
}
}
return(ans);
}
/// This part of RProxy impersonates the remote database:
// login to bank account #id:
public IAcct login(string id)
{
IAcct loggedinAccount = null;
// call the remote database via RPC to login and receive in return
// a handle to the remote bank acct:
remoteAccount = new Account(id, (int)remoteDatabase.loginRemote(id)); // method rpcToDatabase is coded below
if (remoteAccount != null)
{
accountid = id;
loggedinAccount = this; // This object here also impersonates the bank account,
// so that it can execute the RPCs for account lookups.
}
return(remoteAccount);
}
private string accountId; // string ID of the account, if any, that is opened for transactions
public ATMControl(IDB db)
{
database = db;
acct = null; // no account opened just yet
}
