混乱している数値書式の例外

Question

私のパース・ダブルは、その情報が次のようになっているので、例外が発生しているようです：スレッド「AWT-EventQueue-0」の例外java.lang.NumberFormatException：空文字列 another likely

public double withdrawl(double currentBal, double withdrawlAmount) throws InsufficientFunds{ 
    int i =0 ; 
    double overDraw = 0 ; 
    try{ 
    //verifies that input was numeric and evenly divisible by 20 
    if(withdrawlAmount % 20 == 0){ 
    if(i>4){ 
     if(currentBal>1.5){ 
     currentBal = currentBal-1.5 ; 
     }else{ 
     JOptionPane.showMessageDialog(null, "Insufficient funds"); 
     overDraw = currentBal-1.5 ; 
     throw new InsufficientFunds(overDraw); 
     } 
    } 
    //stops withdrawl for insufficient funds 
    if(currentBal<withdrawlAmount) { 
     JOptionPane.showMessageDialog(null, "Insufficient funds"); 
     overDraw = currentBal-withdrawlAmount ; 
     throw new InsufficientFunds(overDraw); 
    }else { 
     currentBal=currentBal-withdrawlAmount ; 
    } 
    i++ ; 
    }else { 
    JOptionPane.showMessageDialog(null, "Please enter a withdarl amount that is divisible by 20"); 
    } 
    }catch (InsufficientFunds ex){ 
     ex.getAmount(); 
    } 
    return currentBal ; 
} 




public class ATM extends JFrame implements ActionListener { 
JButton withdraw, deposit, transfer, balance ; 
JTextField input ; 
boolean checkingActive = true ; 
public double checkingBal = 0 ; 
public double savingsBal = 0 ; 

メインクラス：

容疑者は方法の私のtry catchブロックにもかかわらず、それが報告されていない例外です確信している

account1.withdrawl(checkingBal, changeValue) ; 

が呼び出されています

ATM(){ 
withdraw = new JButton ("Withdraw") ; 
deposit = new JButton ("Deposit") ; 
transfer = new JButton ("Transfer") ; 
balance = new JButton ("Balance") ; 
input = new JTextField (12) ; 
input.setText("0") ; 
input.setEditable(true) ; 

JRadioButton checking = new JRadioButton("Checking", true) ;; 
JRadioButton savings = new JRadioButton("Savings") ; 
this.add(checking); 
this.add(savings); 
ButtonGroup acctSelector = new ButtonGroup(); 
acctSelector.add(checking); 
acctSelector.add(savings); 


add(withdraw); 
add(deposit); 
add(transfer); 
add(balance); 
add(input); 

//assigns buttons to logic gorup 
ButtonGroup accountChoice = new ButtonGroup(); 
accountChoice.add(checking) ; 
accountChoice.add(savings) ; 

input = new JTextField(6) ; 

//assigns listeners to buttons 
withdraw.addActionListener(this) ; 
deposit.addActionListener(this) ; 
transfer.addActionListener(this) ; 
balance.addActionListener(this) ; 

setSize(500,400) ; 
setLayout(new FlowLayout()) ; 
setTitle("MoneyBank ATM") ; 
} 

//acceses account changes 
public void actionPerformed(ActionEvent e){ 
double changeValue = Double.parseDouble(input.getText().trim()); 
Account account1 = new Account() ; 
if(checkingActive==true){ 
    if(e.getSource()== withdraw){ 
     account1.withdrawl(checkingBal, changeValue) ; 
    } else if(e.getSource()== deposit) { 
     account1.deposit(checkingBal, changeValue) ; 
    } else if(e.getSource()== transfer){ 
     account1.transfer(checkingBal, changeValue) ; 
    } else { 
     account1.balance(checkingBal) ; 
    } 
} else { 
    if(e.getSource()== withdraw){ 
     account1.withdrawl(savingsBal, changeValue) ; 
    } else if(e.getSource()== deposit) { 
     account1.deposit(savingsBal, changeValue) ; 
    } else if(e.getSource()== transfer){ 
     account1.transfer(savingsBal, changeValue) ; 
    } else { 
     account1.balance(savingsBal) ; 
    } 
} 
JOptionPane.showMessageDialog(null, "Current balances are: \n Savings: " + savingsBal + "\n Checking: "+ checkingBal); 
} 

//constructs atm object/GUI 
public static void main(String[] args){ 
ATM account=new ATM(); 
account.setVisible(true); 
account.setLocation(200,200); 
account.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
} 

public boolean pickAccount(boolean k) { 
    checkingActive = k ; 
    return checkingActive ; 
} 

} 

Answer 1

変数入力用に2つの異なるJTextFieldインスタンスを作成しています。

最初：

input = new JTextField(12); 
input.setText("0"); 
input.setEditable(true); 

秒：

input = new JTextField(6); 

ですから、フィールドに番号を記入し、プロセスに値を送信するとき、何を受けていることは、「空の値であります"そして、あなたのアプリケーションがその空からダブルを生成しようと最後の原因：

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: empty String 

をあなたはコメントまたは削除2番目のインスタンスを、アプリケーションが動作することができます。