import javax.swing.JOptionPane;
  public class informations{
    public static void main(String[] args){
          String nameofEmployeeString=JOptionPane.showInputDialog(
        "Enter employee's name:");
        String hoursWorkedString=JOptionPane.showInputDialog(
        "Enter number of hours worked in a week:");
        double hoursWorked=Double.parseDouble(hoursWorkedString);
        String hourlyPayRateString=JOptionPane.showInputDialog(
        "Enter hourly pay rate:");
        double hourlyPayRate=Double.parseDouble(hourlyPayRateString);
        String federalTaxWithholdingRateString=JOptionPane.showInputDialog(
        "Enter federal tax withholding rate:");
        double federalTaxWithholdingRate=Double.parseDouble(federalTaxWithholdingRateString);
        String stateTaxWithholdingRateString=JOptionPane.showInputDialog(
        "Enter state tax withholding rate:");
        double stateTaxWithholdingRate=Double.parseDouble(stateTaxWithholdingRateString);
        double grossPay=hourlyPayRate*hoursWorked;
        double federalWithholding=grossPay*federalTaxWithholdingRate;
        double stateWithholding=grossPay*stateTaxWithholdingRate;
        double totalDeduction=federalWithholding+stateWithholding;
        double netPay=grossPay - totalDeduction;
        String output="Employee's Name:" + nameofEmployee+"\n"+
                      "Hours Worked:"+hoursWorked+"\n"+
                      "Pay Rate:$"+hourlyPayRate+"\n"+
                      "Gross Pay:$"+grossPay+"\n"+
                      "Deductions:\n"+
                      "\t Federal Withholding(" + federalTaxWithholdingRate+"%):$"+federalWithholding+"\n"+
                      "\t State Withholding(" + stateTaxWithholdingRate+"%):$"+stateWithholding+"\n"+
                      "\t Total Deduction:$"+totalDeduction+"\n"+
                      "Net Pay:$" + netPay;
         JOptionPane.showMessageDialog(null,output);
  }
}

但是一执行就是这样的

哎呀，电脑上图也不行，就是说那个nameofEmployee那里出问题了  找不到符号

swing 无能为力