CS 61B lab6

part one 

在main中加上try／catch(IOException e1){}) 把两个readline包含进去即可

bug是，当withdraw负数时：

part two

在findAccount函数中new throws然后每个相关函数都要throws，最后到throw到main后catch。

part three

把题目看仔细，说的是withdraw和deposit都有错的所以两个函数里面都要new BadTransactionException，一直throw到main再catch。

Extra

有两种方法：

方法一：把catch后的readline语句移动到catch前，也就是while里try的最后。

方法二：在catch(BadTransactionException e3){System.err.println(e3);}语句后面加上continue变成

catch(BadTransactionException e3){System.err.println(e3);continue;）

两种方法都可以。但是题目貌似要求moving哈哈。

测试图片：(除了格式有点小问题，有时候exception会在repeat command后面或者不换行有时候又是正确的格式。。。并不知道为什么。。。)

 放下代码吧，发现和熊孩子的有些不同（accountData里面没有throw，都在main里catch的）：

package lab6;

/* BankApp.java */

import java.io.*;
import sortedlist.*;

/**
 *  A bank application.  Allows a user to create and manipulate 
 *  banking accounts, using an ATM that is shared by all banking applications.
 */
public class BankApp {
  private BufferedReader bReader =
          new BufferedReader(new InputStreamReader(System.in));
  private VirtualTeller ATM = new VirtualTeller();

  public static void main(String[] args) {
    greeting();
    usage();
    BankApp bankApp = new BankApp();
    try{
    String command = bankApp.readLine("--> ");
    
    while (!command.equals("quit")) {
      try{
    if (command.equals("open")) {
      bankApp.open();
    } else if (command.equals("deposit")) {
      bankApp.doDeposit();
    } else if (command.equals("withdraw")) {
      bankApp.doWithdraw();
    } else if (command.equals("inquire")) {
      bankApp.doInquire();
    } else {
      System.err.println("Invalid command: " + command);
      usage();
    }
    command = bankApp.readLine("--> ");
    } catch(IOException e) {
    System.err.println(e);
      }
      catch(BadAccountException e2){System.err.println(e2);}
      catch(BadTransactionException e3){System.err.println(e3);}
//      command = bankApp.readLine("--> ");  另一种方法：在catch后面加上continue
    }
   }catch(IOException e1){}
    
  }

  public BankApp() {
    // The field declarations have initializers;
    //   no initialization is needed here.
  }

  /**
   *  open() prompts the user to create an account and creates one in the ATM.
   *  @exception IOException if there are problems reading user input.
   */
  private void open() throws IOException {
    String name = readLine("Enter name: ");
    int newNum = ATM.openAccount(name);

    System.out.println(name + ", your new account number is: " + newNum);
    System.out.println("Thanks for opening an account with us!");
  }

 /**
  *  doDeposit() prompts the user for an account number and tries to perform a 
  *  deposit transaction on that account. 
  *  @exception IOException if there are problems reading user input.
  */
  private void doDeposit() throws IOException,BadAccountException,BadTransactionException{
    // Get account number.
    int acctNumber = readInt("Enter account number: ");
    int amount = readInt("Enter amount to deposit: ");

    ATM.deposit(acctNumber, amount);
    System.out.println("New balance for #" + acctNumber + " is " +
                       ATM.balanceInquiry(acctNumber));
  }

  /**
   *  doWithdraw() prompts the user for an account number and tries
   *  to perform a withdrawal transaction from that account.
   *  @exception IOException if there are problems reading user input.
   */
  private void doWithdraw() throws IOException,BadAccountException,BadTransactionException{
    // Get account number.
    int acctNumber = readInt("Enter account number: ");
    int amount = readInt("Enter amount to withdraw: ");

    ATM.withdraw(acctNumber, amount);
    System.out.println("New balance for #" + acctNumber + " is " +
                       ATM.balanceInquiry(acctNumber));
  }

  /**
   *  doInquire() prompts the user for an account number, then attempts to
   *  discover and print that account's balance.
   *  @exception IOException if there are problems reading user input.
   */
  private void doInquire() throws IOException,BadAccountException{
    int acctNumber = readInt("Enter account number: ");

    System.out.println("Balance for #" + acctNumber + " is " +
                       ATM.balanceInquiry(acctNumber));
  }

  /**
   *  greeting() displays a greeting message on the screen.
   */
  private static void greeting() {
    System.out.println("-------------------");
    System.out.println("Welcome to the bank");
    System.out.println("-------------------");
    System.out.println();
  }

  /**
   *  usage() displays instructions on using the command line arguments.
   */
  private static void usage() {
    System.out.println("Valid commands are: " +
                       "open, deposit, withdraw, inquire, quit");
  }

  /**
   *  readLine() prints the given prompt and returns a string from the
   *  input stream.
   *  @param prompt is the string printed to prompt the user.
   */
  private String readLine(String prompt) throws IOException {
    System.out.print(prompt);
    System.out.flush();
    return bReader.readLine();
  }

  /**
   *  readInt() returns an integer from the input stream after prompting
   *  the user.
   *  @param prompt is the string printed to prompt the user.
   *  @return an int read from the user.
   */
  private int readInt(String prompt) throws IOException {
    String text = readLine(prompt);
    return Integer.valueOf(text).intValue();
  }
}

package lab6;

/*  VirtualTeller.java */

import sortedlist.*;

/**
 *  An implementation of a virtual automated teller machine.
 **/
public class VirtualTeller {
  private static int nextAccountID = 100;
  private SortedList accounts;

  /**
   *  Constructs a new virtual teller.
   **/
  public VirtualTeller() {
    accounts = new SortedList();
  }

  /**
   *  openAccount() creates a new account for the customer "name".
   *  @param name the customer's name.
   *  @return the new account's ID number.
   **/
  public int openAccount(String name) {
    AccountData newData = new AccountData(name, nextAccountID);
    accounts.insert(newData);

    nextAccountID++;
    return newData.getNumber();
  }

  /**
   *  withdraw() withdraws "amount" dollars from the account whose number is
   *  "acct".  Assumes that amount >= 0.  If "acct" is invalid, no action is
   *  taken.
   *  @param acct is an account number.
   *  @param amount an amount of money.
   */
  public void withdraw(int acct, int amount) throws BadAccountException,BadTransactionException{
    AccountData account = findAccount(acct);

    if (account == null) {   // Didn't find the account.
      System.out.println("Error:  Couldn't find account number `" +
                         acct + "'" );
    } else {
      if(amount<0){throw new BadTransactionException(amount);}
      account.withdraw(amount);
    }
  }

  /**
   *  deposit() deposits "amount" dollars into the bank account whose number is
   *  "acct".  Assumes that amount >= 0.  If "acct" is invalid, no action is
   *  taken.
   *  @param acct is an account number.
   *  @param amount an amount of money.
   */
  public void deposit(int acct, int amount) throws BadAccountException,BadTransactionException{
    AccountData account = findAccount(acct);

    if (account == null) { 
      System.out.println("Error:  Couldn't find account number `" +
                         acct + "'");
    } else {
    if(amount<0){throw new BadTransactionException(amount);}
      account.deposit(amount);
    }
  }

  /**
   *  balanceInquiry() finds the balance on the account whose number is "acct".
   *  If "acct" is an invalid number, returns -1.
   *  @param acct an account number.
   *  @return the balance, or -1 if the account number is invalid.
   */
  public int balanceInquiry(int acct) throws BadAccountException{
    AccountData account = findAccount(acct);

    if (account == null) {
      System.out.println("Error:  Couldn't find account number `" +
                         acct + "'" );
      return -1;
    } else {
      return account.getBalance();
    }
  }

  /**
   *  findAccount() gets the AccountData object associated with account number
   *  "acct".  If "acct" does not refer to a valid account, returns null.
   *  @param acct is an account number.
   *  @return the AccountData object associated with the account number.
   */
  private AccountData findAccount(int acct) throws BadAccountException{
    AccountData account = (AccountData) accounts.find(acct);
    if(account==null){
        throw new BadAccountException(acct);
    }
    return account;
  }
}

package lab6;

/* BadAccountException.java */

/**
 *  Implements an exception that should be thrown for nonexistent accounts.
 **/
public class BadTransactionException extends Exception {

  public int accountNumber;  // The invalid account number.

  /**
   *  Creates an exception object for nonexistent account "badAcctNumber".
   **/
  public BadTransactionException(int badAcctNumber) {
    super("Invalid input number: " + badAcctNumber);

    accountNumber = badAcctNumber;
  }
}