Java GUI-出生日期

Question

用户输入员工的出生日期，但任务要求您验证条目。

我希望应用程序显示的是一个错误，当用户输入生日的日期为33或什么，因为在B. O. D.中没有这样的一天。

此外，当用户单击“保存”时，文本字段中的数据应保存到arraylist中。当用户单击“打印”时，保存在arraylist中的数据应显示为以前的信息。

java prettyprint-override">public class JavaGUI {

    ArrayList<JavaMethods> arl10 = new ArrayList<JavaMethods>();
    ArrayList<JavaMethods> arl11 = new ArrayList<JavaMethods>();

    JFrame frame;
    JPanel panel;

    JLabel labelA = new JLabel("Employee Information");
    JLabel labelB = new JLabel("Employee Birthdate");

    JLabel label1 = new JLabel("Employee Name:");
    JTextArea txt1 = new JTextArea("                ");
    JLabel label2 = new JLabel("Employee Address:");
    JTextArea txt2 = new JTextArea("                ");
    JLabel label3 = new JLabel("Employee Age:");
    JTextArea txt3 = new JTextArea("                ");
    JLabel label4 = new JLabel("Day:");
    JTextArea txt4 = new JTextArea("                ");
    JLabel label5 = new JLabel("Month:");
    JTextArea txt5 = new JTextArea("                ");
    JLabel label6 = new JLabel("Year:");
    JTextArea txt6 = new JTextArea("                ");

    JButton btn1 = new JButton("Clear");
    JButton btn2 = new JButton("Save");
    JButton btn3 = new JButton("Print");

    JRadioButton male = new JRadioButton("Male");
    JRadioButton female = new JRadioButton("Female");

    ButtonGroup g1 = new ButtonGroup();

    ActionListener act1 = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {

            txt1.setText("                ");
            txt2.setText("                ");
            txt3.setText("                ");
            txt4.setText("                ");
            txt5.setText("                ");
            txt6.setText("                ");

        }

    };

    ActionListener act2 = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            try {
                int day = Integer.parseInt(txt4.getText());
                if(day <= 32) {
            
            JOptionPane.showMessageDialog(frame, "Employee Information has been saved, Click PRINT to show them!");
            JavaMethods arl10 = new JavaMethods(txt1.getText().trim(), txt2.getText().trim(), male.getText(),Integer.parseInt(txt3.getText().trim()), Integer.parseInt(txt4.getText().trim()),Integer.parseInt(txt5.getText().trim()), Integer.parseInt(txt6.getText().trim()));
                
            arl11.add(arl10);
                }
                else {
                    System.out.println("wrong day");
                }
            }
            catch(NumberFormatException ex)
            {
                System.out.println("Exception : "+ex);
            }
        }
    };

    ActionListener act3 = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {

            try {
    System.out.println(arl11);

                    JavaMethods arl10 = new JavaMethods(txt1.getText().trim(), txt2.getText().trim(), female.getText(),
                            Integer.parseInt(txt3.getText().trim()), Integer.parseInt(txt4.getText().trim()),
                            Integer.parseInt(txt5.getText().trim()), Integer.parseInt(txt6.getText().trim()));

                    arl11.add(arl10);

                    System.out.print("Previously Stored Information" + " " + arl11);
                    System.out.println();
                    System.out.println(arl10.toString());

                }

             catch (Exception e1) {
                System.out.println(
                        "Unable to perform the task, Please make sure you have entered the right DataType, Or make sure you have filled all the blanks.");

            }
        }

    };

    public JavaGUI() {
        frame = new JFrame();
        panel = new JPanel();

        frame.setPreferredSize(new Dimension(500, 500));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.setTitle("HR System");

        btn1.addActionListener(act1);
        btn2.addActionListener(act2);
        btn3.addActionListener(act3);

        panel.add(labelA);
        panel.add(label1);
        panel.add(txt1);
        panel.add(label2);
        panel.add(txt2);
        panel.add(label3);
        panel.add(txt3);
        panel.add(labelB);
        panel.add(label4);
        panel.add(txt4);
        panel.add(label5);
        panel.add(txt5);
        panel.add(label6);
        panel.add(txt6);

        g1.add(male);
        g1.add(female);

        panel.add(btn1);
        panel.add(btn2);
        panel.add(btn3);
        panel.add(male);
        panel.add(female);
        frame.add(panel);
        frame.pack();
        frame.setVisible(true);

    }

}

Answer 1

若要比较作为文本输入的数字，请解析。

String dayInput = "42" ;
int day = Integer.parseInt( dayInput ) ;
if( day > 32 ) { … handle invalid input }

要验证一个日期，实例化一个LocalDate对象，同时捕获DateTimeParseExc0019