当我放置检查和保存对象并尝试在另一个类中调用它时，它实际上不起作用，并且它给我一个语法错误。我在下面粘贴了我的java代码。无论出于何种原因，帐户都有问题。有什么我应该改变以避免出现这些错误吗？
给出的错误是： 线程“main”中的异常java.lang.Error：未解决的编译问题： SavingsAccount无法解析为某种类型 SavingsAccount无法解析为某种类型 客户无法解析为某种类型 银行无法解决 accountentered无法解析为变量 accountentered无法解析为变量 transAccount无法解析为变量 transAccount无法解析为变量 SavingsAccount无法解析为某种类型 SavingsAccount无法解析为某种类型 客户无法解析为某种类型 客户无法解析为某种类型 重复的局部变量 CreditAccount无法解析为某种类型 CreditAccount无法解析为某种类型 重复的局部变量firstName 重复的局部变量lastName 重复的局部变量pnumber 客户无法解析为某种类型 重复的局部变量newCustomer 客户无法解析为
类型at ProjectBank.main(ProjectBank.java:25)
import java.io.InputStream;
import java.util.Scanner;
public class CustomerDemo
{
class Customer
{
//two objects/ saving and checking
Account Saving = new Account();
Account Checking = new Account();
public Customer(InputStream in)
{
// TODO Auto-generated constructor stub
}
boolean deposit(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.deposit(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Saving.deposit(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
boolean withdraw(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.withdraw(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Saving.withdraw(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
boolean transfer(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.withdraw(amount);
currentBalanceSaving = this.Checking.deposit(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Checking.withdraw(amount);
currentBalanceChecking = this.Checking.deposit(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
}
void printBalance()
{
}
}
class Account
{
double balance;
//the constructor tells the customer that there are zero dollars in the account.
Account()
{
balance = 0;
}
//deposit money
double deposit( double depAmount )
{
balance= balance + depAmount;//balance+ = depAmount
return balance;
}
double withdraw( double withAmount )
{
balance= balance - withAmount;//balance- = withAmount
return balance;
}
double transferToSaving(double transAmount)
{
Checking.balance = balance - transAmount;
Saving.balance = balance + transAmount;
}
double transferToChecking(double transAmount)
{
Checking.balance = balance - transAmount;
Saving.balance = balance + transAmount;
}
double getBalance()
{
return balance;
}
}
class run
{
public void main(String[] args)
{
// TODO Auto-generated method stub
Scanner in = new Scanner(System.in);
Customer customer = new Customer(System.in);
int accountChoice; // show which account needs to be chosen.
String cusSel; //for customer selection.
double money;
do
{
System.out.println("main menu to be selected: " );
System.out.println("1.deposit " );
System.out.println("2.withdraw " );
System.out.println("3.transfer " );
System.out.println("4.print balance " );
System.out.println("q.quit " );
cusSel=in.next();
switch(cusSel.charAt(0))
{
case '1':
System.out.println("please select account: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please imput the deposit amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.deposit(money, "Checking");
}
else if(accountChoice==2)
{
customer.deposit(money, "Saving");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '2':
System.out.println("Please select account: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please input the withdraw amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.withdraw(money, "Checking");
}
else if(accountChoice==2)
{
customer.withdraw(money, "Saving");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '3':
System.out.println("please select an account to transfer from: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please input the withdraw amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.transfer(money, "saving");
}
else if(accountChoice==2)
{
customer.transfer(money, "checking");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '4':
customer.printBalance();
break;
case 'q':
System.out.println("transaction complete, please have a nice day");
break;
default:
System.out.println("invalid choice.");
}
} while (cusSel.charAt(0)!= 'q' && cusSel.charAt(0)!= 'Q');
}
private void getAccountChoice(int accountChoice) {
// TODO Auto-generated method stub
}
}
答案 0 :(得分：0)
您收到错误是因为您在客户类中声明了对象，并且您尝试从帐户访问它们作为本地变量。
您遇到此错误的原因是您的类结构。类只应具有与您的类的单个实例直接相关的方法和字段。例如，在您的情况下，帐户类具有＆＃34;余额＆＃34;这是100％正确，然后它有像＆＃34; transferToSavings（）＆＃34; （甚至不使用该变量）与CONNECTION（在这种情况下是客户，或通常是交易）相关，在支票账户和储蓄账户之间而不是账户本身。
转移的基本结构应该是这样的：
Customer{
Account Saving = new Account();
Account Checking = new Account();
//you have something similar with input control
void tranferFunds(Account from, Account to, double amount){
from.Withdraw(amount);
to.Deposit(amount);
}
}
class Account
{
double balance;
Account()
{
balance = 0;
}
void deposit( double amount)
{
balance+= amount;
}
void withdraw( double amount)
{
balance-= amount;
}
double getBalance()
{
return balance;
}
}
修改：我注意到您已经在Customer中使用了transfer（）方法，该方法应该可以正常工作，因此您不必更改您的客户类别。
Edit2：它无法解析客户，因为您的客户类位于CustomerDemo类中。您可以一起删除CustomerDemo类（附带括号）
编辑3：这里调试了您的代码，没有使用account.transferTo / from方法。我使用在线编译器，所以我没有测试输入，但没有更多的语法错误：
import java.io.InputStream;
import java.util.Scanner;
public class run
{
public static void main(String[] args)
{
// TODO Auto-generated method stub
Scanner in = new Scanner(System.in);
Customer customer = new Customer(System.in);
int accountChoice; // show which account needs to be chosen.
String cusSel; //for customer selection.
double money;
do
{
System.out.println("main menu to be selected: " );
System.out.println("1.deposit " );
System.out.println("2.withdraw " );
System.out.println("3.transfer " );
System.out.println("4.print balance " );
System.out.println("q.quit " );
cusSel=in.next();
switch(cusSel.charAt(0))
{
case '1':
System.out.println("please select account: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please imput the deposit amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.deposit(money, "Checking");
}
else if(accountChoice==2)
{
customer.deposit(money, "Saving");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '2':
System.out.println("Please select account: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please input the withdraw amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.withdraw(money, "Checking");
}
else if(accountChoice==2)
{
customer.withdraw(money, "Saving");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '3':
System.out.println("please select an account to transfer from: " );
System.out.println("1. Checking" );
System.out.println("2. Saving " );
accountChoice=in.nextInt();
if((accountChoice==1)||(accountChoice==2))
{
System.out.println("please input the withdraw amount: " );
money=in.nextDouble();
if(accountChoice==1)
{
customer.transfer(money, "saving");
}
else if(accountChoice==2)
{
customer.transfer(money, "checking");
}
}
else
{
System.out.println("invalid choice. your choice does not exsist");
break;
}
break;
case '4':
customer.printBalance();
break;
case 'q':
System.out.println("transaction complete, please have a nice day");
break;
default:
System.out.println("invalid choice.");
}
} while (cusSel.charAt(0)!= 'q' && cusSel.charAt(0)!= 'Q');
}
private void getAccountChoice(int accountChoice) {
// TODO Auto-generated method stub
}
}
class Customer
{
//two objects/ saving and checking
Account Saving = new Account();
Account Checking = new Account();
public Customer(InputStream in)
{
// TODO Auto-generated constructor stub
}
boolean deposit(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.deposit(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Saving.deposit(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
boolean withdraw(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.withdraw(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Saving.withdraw(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
boolean transfer(double amount, String acc)
{
double currentBalanceChecking, currentBalanceSaving;// this currentBalence is subtracted from and account.
boolean retVal = false;
switch (acc)
{
case "Checking":
if(amount >=0)
{
currentBalanceChecking = this.Checking.withdraw(amount);
currentBalanceSaving = this.Checking.deposit(amount);
retVal = true;
}
break;
case "Saving":
if(amount >=0)
{
currentBalanceSaving = this.Checking.withdraw(amount);
currentBalanceChecking = this.Checking.deposit(amount);
retVal = true;
}
break;
default:
System.out.println("You entered an invalid number.");
}
return retVal;
}
void printBalance()
{
}
}
class Account
{
double balance;
//the constructor tells the customer that there are zero dollars in the account.
Account()
{
balance = 0;
}
//deposit money
double deposit( double depAmount )
{
balance= balance + depAmount;//balance+ = depAmount
return balance;
}
double withdraw( double withAmount )
{
balance= balance - withAmount;//balance- = withAmount
return balance;
}
double getBalance()
{
return balance;
}
}