我在将日期从JDateChooser存储到MySQL数据库中时遇到问题

Question

我在将数据从GUI传递到MySQL数据库时遇到问题。我正在将JTextField和JDateChooser的信息收集到数据库中。除日期外，其他一切都有效。我尝试了在网上找到的多种方法，但都没有奏效。我还检查了该表，以确保在我的"patientinfo"表中启用了"DATE"数据类型。如果我删除JDateChooser，我的查询就会工作。否则，我将收到以下错误消息：

Java.lang.NullPointerException

我将把我的源代码包含在这条消息中。

//Event handler adds records
//to the database
JButton subInfoBtn = new JButton("SUBMIT AND CONTINUE");
subInfoBtn.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent arg0) {
            try {
                //Invokes "javaconnect" class
                //to link to MySQL database
                conn = javaconnect.ConnecrDb();
                //Invokes SQL Statement from "Connection" Object
                pst = conn.createStatement();
                //SQL query commands event handler to access
                //"patientinfo" table, to insert data to columns.
                pst.executeUpdate("INSERT into patientinfo(firstName, lastName, DOB, age, SSN, "
                                  + "address, phone,email, emergencycontact, emergencyphone) "
                                  + "VALUES" + "('"+firstTxt.getText() + "', '" + lastTxt.getText()
                                  + "', '" + DOBTxt.getDate() + "' ,'" + ageTxt.getText() + "', '"
                                  + ssnTxt.getText() + "', "+ " '" + addressTxt.getText() +"',
                                  '"+phoneTxt.getText()+"'  , '"+emailTxt.getText()+"'  ,
                                  '"+emergencyTxt.getText()+"'  , '"+emergPhoneTxt.getText()+"'  )");

                //Closes Database Connection
                conn.close();
                JOptionPane.showMessageDialog(null, "Pantient Information Saved Succesfully");
            } catch (Exception e) {
                JOptionPane.showMessageDialog(null, e);
            }
        }
    });
    subInfoBtn.setFont(new Font("Tahoma", Font.BOLD, 14));
    subInfoBtn.setBounds(305, 286, 220, 23);
    contentPane.add(subInfoBtn);
//Also, I have tried to use SimpleDateFormat and
//((JTextField)jDateChooser1.getDateEditor().getUiComponent()).getText();
//Without any luck.  I am also aware of using Prepare Statement to avoid SQL injections, but
//I would like to solve the JDateChooser bonding data dilema into MySQL database.

Answer 1

试试这样的东西将您输入的java.util.Date转换为java.sql.Date，以便将其存储到Mysql数据库中，因为Mysql存储格式为yyyy-MM-dd 的Date

public static java.sql.Date convertUtilDateToSqlDate(java.util.Date date){
    if(date != null) {
        java.sql.Date sqlDate = new java.sql.Date(date.getTime());
        return sqlDate;
    }
    return null;
}

然后按照他的方式

PreparedStatement statement = conn.prepareStatement("INSERT INTO patientinfo"+
                                     "(firstName, lastName, DOB, age, SSN, address," +
                                     "phone,email, emergencycontact, emergencyphone)"+
                                     "VALUES(?,?,?,?,?,?,?,?,?,?)");
statement.setTimestamp(1,sqlDate);
statement.setString(1,firstTxt.getText());
statement.setString(2,lastTxt.getText());
statement.setDate(3,convertUtilDateToSqlDate(DOBTxt.getDate()));
statement.setString(4,ageTxt.getText());
statement.setString(5,ssnTxt.getText());
statement.setString(6,addressTxt.getText());
statement.setString(7,phoneTxt.getText());
statement.setString(8,emailTxt.getText());
statement.setString(9,emergencyTxt.getText());
statement.setString(10,emergPhoneTxt.getText());
int i = statement.executeUpdate();
if(i>0){
    System.out.println("Successfull");
 }

我希望你能做必要的异常处理和连接关闭

Answer 2

java.sql.Date date = new java.sql.Date(dateChooser.getDate().getTime());

将Date转换为sql对象，然后存储在数据库中。希望它能起作用。