Question

我的代码对我来说看起来很好，但我一直得到nullpointerexception。我正在输入一个如下所示的文本文件：

Kermit D.Frogge 17.25 5.25 0.0 8.0 1.5 8.0 2.25 7.75 0.0 8.0 2.0

这是我的一些代码：

private static BufferedReader br;
private static StringTokenizer strTkn;


private static String st, firstName, middleInitial, lastName;
private static double monRegHours, monOverHours, tuesRegHours, tuesOverHours,      wedRegHours, wedOverHours,
thurRegHours, thurOverHours, friRegHours, friOverHours;
private static double totalRegHours, totalOverHours, hourlyWage, regularPay, overtimePay, weeklyPay;
private static JFileChooser chooser;


public static void main (String args []) throws IOException 
{
chooser();
getData();
calcpay();
printresult();
}


public static void chooser() throws IOException
{
JFileChooser chooser=new  JFileChooser();
int returnVal = chooser.showOpenDialog(null);
if(returnVal == JFileChooser.APPROVE_OPTION) 
{
  File f = chooser.getSelectedFile();
  br=new BufferedReader(new FileReader(f));
  st="";
  while((st=br.readLine())!=null);
  {
    System.out.println ("Data Line = " + st ); //print the whole line
  }
  }
  }


public static void getData() throws IOException
{
 strTkn = new StringTokenizer(st, " .");

 firstName = strTkn.nextToken();
 middleInitial = strTkn.nextToken();
 lastName = strTkn.nextToken();
 hourlyWage = Double.parseDouble(strTkn.nextToken());

 monRegHours = Double.parseDouble(strTkn.nextToken());
 monOverHours = Double.parseDouble(strTkn.nextToken());

 tuesRegHours = Double.parseDouble(strTkn.nextToken());
 tuesOverHours = Double.parseDouble(strTkn.nextToken());

 wedRegHours = Double.parseDouble(strTkn.nextToken());
 wedOverHours = Double.parseDouble(strTkn.nextToken());

 thurRegHours = Double.parseDouble(strTkn.nextToken());
 thurOverHours = Double.parseDouble(strTkn.nextToken());

 friRegHours = Double.parseDouble(strTkn.nextToken());
 friOverHours = Double.parseDouble(strTkn.nextToken());


}


public static void calcpay()
{
totalRegHours = monRegHours + tuesRegHours + wedRegHours + thurRegHours + friRegHours;
totalOverHours = monOverHours + tuesOverHours + wedOverHours + thurOverHours +    friOverHours;

overtimePay = round(totalOverHours * (1.5 * hourlyWage));
regularPay  = round(hourlyWage * totalRegHours);
weeklyPay = regularPay + overtimePay;
}


public static void printresult()
{
System.out.println("Name: " + firstName + " " + middleInitial + " " + lastName);
System.out.printf("Weekly Pay: " + "$%.2f\n", weeklyPay);
//this allows me to print $x.50 instead of $x.5, and not have repeating decimals
}


public static double round(double num) 
{
// rounding to two decimal places
num *= 100;
int rounded = (int) Math.round(num);
return rounded/100.0;

对不起，如果看起来不好，我的电脑不喜欢复制粘贴

Answer 1

这是一个非常简单的错误。你在while循环后放了一个分号。

while((st=br.readLine())!=null);

删除分号，它会正常工作。

使用Filechooser的NullPointerException？

1 个答案: