java.sql.SQLException:在结果集开始之前。。。如何删除此错误
我使用java和mysql开发了员工工资管理。。 我想生成一份PDF文档。。。 但当我点击“生成工资单”按钮时,就会出现这个错误。。。 我的生成单张按钮代码如下:java.sql.SQLException:在结果集开始之前。。。如何删除此错误,java,mysql,netbeans-8,Java,Mysql,Netbeans 8,我使用java和mysql开发了员工工资管理。。 我想生成一份PDF文档。。。 但当我点击“生成工资单”按钮时,就会出现这个错误。。。 我的生成单张按钮代码如下: enter code here private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { String value = txt_firstn
enter code here
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
String value = txt_firstname.getText();
String value0 = txt_surname.getText();
String value1 = txt_id.getText();
String value2 = txt_desig.getText();
String value3 = txt_dep.getText();
JFileChooser dialog = new JFileChooser();
dialog.setSelectedFile(new File(value +" "+ value0+"-Salary Slip"+".pdf"));
int dialogResult = dialog.showSaveDialog(null);
if (dialogResult==JFileChooser.APPROVE_OPTION){
String filePath = dialog.getSelectedFile().getPath();
try {
// TODO add your handling code here:
String sql ="select * from Deductions where emp_id = '"+value1+"'";
pst=conn.prepareStatement(sql);
rs=pst.executeQuery();
String val = rs.getString(5);
String reason = rs.getString(6);
rs.close();
pst.close();
String sq ="select * from Allowance where emp_id = '"+value1+"'";
pst=conn.prepareStatement(sq);
rs=pst.executeQuery();
int calcTotal = Integer.parseInt(txt_salary.getText());
float x = Float.valueOf(rs.getString(9));
int v = Integer.parseInt(val);
float total = calcTotal +x-v;
Document myDocument = new Document();
PdfWriter myWriter = PdfWriter.getInstance(myDocument, new FileOutputStream(filePath));
myDocument.open();
myDocument.add(new Paragraph("PAY SLIP",FontFactory.getFont(FontFactory.TIMES_BOLD,20,Font.BOLD )));
myDocument.add(new Paragraph(new Date().toString()));
myDocument.add(new Paragraph("-------------------------------------------------------------------------------------------"));
myDocument.add((new Paragraph("EMPLOYEE DETAILS",FontFactory.getFont(FontFactory.TIMES_ROMAN,15,Font.BOLD))));
myDocument.add((new Paragraph("Name of Employee: " +value + " "+value0,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN))));
myDocument.add((new Paragraph("Designation: "+value2,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN))));
myDocument.add((new Paragraph("Department: "+value3,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN))));
myDocument.add(new Paragraph("-------------------------------------------------------------------------------------------"));
myDocument.add(new Paragraph("SALARY",FontFactory.getFont(FontFactory.TIMES_ROMAN,15,Font.BOLD)));
myDocument.add(new Paragraph("Basic Salary: $"+calcTotal,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Overtime: "+rs.getString(2)+" Hours",FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Medical: $" +rs.getString(3),FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Bonus: $"+rs.getString(4),FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Other: $"+rs.getString(5),FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("-------------------------------------------------------------------------------------------"));
myDocument.add(new Paragraph("DEDUCTION",FontFactory.getFont(FontFactory.TIMES_ROMAN,15,Font.BOLD)));
myDocument.add(new Paragraph("Deduction Details: "+reason,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Total Deductions : $"+val ,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("-------------------------------------------------------------------------------------------"));
myDocument.add(new Paragraph("TOTAL PAYMENT",FontFactory.getFont(FontFactory.TIMES_ROMAN,15,Font.BOLD)));
myDocument.add(new Paragraph("Total Earnings: "+rs.getString(9),FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("Net Pay : " +total,FontFactory.getFont(FontFactory.TIMES_ROMAN,10,Font.PLAIN)));
myDocument.add(new Paragraph("-------------------------------------------------------------------------------------------"));
myDocument.newPage();
myDocument.close();
JOptionPane.showMessageDialog(null,"Report was successfully generated");
}
catch(Exception e){
JOptionPane.showMessageDialog(null,e);
}
finally {
try{
rs.close();
pst.close();
}
catch(Exception e){
JOptionPane.showMessageDialog(null,e);
}
}
}
}
在使用getString等之前,您需要调用
ResultSet#next()
:
String sql ="select * from Deductions where emp_id = '"+value1+"'";
pst=conn.prepareStatement(sql);
rs=pst.executeQuery();
if(rs.next()) { // here
String val = rs.getString(5);
String reason = rs.getString(6);
}
next()
call每次将光标向前移动一行。结果集光标最初位于第一行之前;对方法next的第一次调用使第一行成为当前行;第二次调用使第二行成为当前行,依此类推。在使用getString等之前,需要调用ResultSet\next()
:
String sql ="select * from Deductions where emp_id = '"+value1+"'";
pst=conn.prepareStatement(sql);
rs=pst.executeQuery();
if(rs.next()) { // here
String val = rs.getString(5);
String reason = rs.getString(6);
}
next()
call每次将光标向前移动一行。结果集光标最初位于第一行之前;对方法next的第一次调用使第一行成为当前行;第二次呼叫使第二行成为当前行,依此类推。显示的错误是哪一行?显示的错误是哪一行?您是在我最近更新应答后还是之前尝试的?你现在可以试试吗?你是在我最近更新答案之后还是之前尝试的?你现在能试试吗?