Question

所以这是我的代码：

package Gui;

import java.sql.*;

import java.awt.BorderLayout;
import java.awt.EventQueue;

import javax.swing.*;
import javax.swing.border.EmptyBorder;

import net.proteanit.sql.DbUtils;

import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;

public class accounts extends JFrame {

    private JPanel contentPane;
    private JTable table;
    private JTable table_1;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    accounts frame = new accounts();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    Connection connection = null;
    private JTextField textField;
    private JTextField textField_1;
    private JTextField textField_2;
    private JPasswordField passwordField;


    /**
     * Create the frame.
     */
    public accounts() {
        connection = sqliteConnection.dbConnector();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 700, 400);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);

        JButton btnNewButton = new JButton("Load Accounts");
        btnNewButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) 
            {
                try {

                    String query = "select * from Users";
                    PreparedStatement pst = connection.prepareStatement(query);
                    ResultSet rs = pst.executeQuery();
                    table_1.setModel(DbUtils.resultSetToTableModel(rs));


                } catch (Exception e1) {
                    e1.printStackTrace();
                }
            }
        });
        btnNewButton.setBounds(500, 25, 150, 30);
        contentPane.add(btnNewButton);

        table = new JTable();
        table.setBounds(100, 256, 261, -183);
        contentPane.add(table);

        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setBounds(250, 75, 400, 150);
        contentPane.add(scrollPane);

        table_1 = new JTable();
        scrollPane.setViewportView(table_1);

        JLabel lblNewLabel = new JLabel("UserName");
        lblNewLabel.setBounds(10, 10, 100, 20);
        contentPane.add(lblNewLabel);

        JLabel lblNewLabel_1 = new JLabel("Password");
        lblNewLabel_1.setBounds(10, 70, 100, 20);
        contentPane.add(lblNewLabel_1);

        JLabel lblNewLabel_2 = new JLabel("Email");
        lblNewLabel_2.setBounds(10, 130, 100, 20);
        contentPane.add(lblNewLabel_2);

        JLabel lblNewLabel_3 = new JLabel("PhoneNo");
        lblNewLabel_3.setBounds(10, 190, 100, 20);
        contentPane.add(lblNewLabel_3);

        textField = new JTextField();
        textField.setBounds(10, 40, 100, 20);
        contentPane.add(textField);
        textField.setColumns(10);

        passwordField = new JPasswordField();
        passwordField.setBounds(10, 100, 100, 20);
        contentPane.add(passwordField);

        textField_1 = new JTextField();
        textField_1.setBounds(10, 160, 100, 20);
        contentPane.add(textField_1);
        textField_1.setColumns(10);

        textField_2 = new JTextField();
        textField_2.setBounds(10, 220, 100, 20);
        contentPane.add(textField_2);
        textField_2.setColumns(10);

        JButton btnNewButton_1 = new JButton("Add");
        btnNewButton_1.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) 
            {
                try
                {
                    String query = "insert into Users (NickName, Password, Email, PhoneNo) values (?, ?, ?, ?)";
                    PreparedStatement pst = connection.prepareStatement(query);
                    pst.setString(1, textField.getText() );
                    pst.setString(2, passwordField.getName() );
                    pst.setString(3, textField_1.getText() );
                    pst.setString(4, textField_2.getText() );

                    pst.execute();

                    JOptionPane.showMessageDialog(null, "Succesfully Registered");

                    pst.close();

                }catch (Exception e)
                {

                    e.printStackTrace();

                }
            }
        });
        btnNewButton_1.setBounds(130, 40, 100, 25);
        contentPane.add(btnNewButton_1);


    }
}

我目前正在进行任务，一切正常，直到我点击添加按钮然后我收到错误消息说：

java.sql.SQLException: The prepared statement has been finalized
    at org.sqlite.core.NativeDB.throwex(NativeDB.java:429)
    at org.sqlite.core.NativeDB.reset(Native Method)
    at org.sqlite.jdbc3.JDBC3PreparedStatement.execute(JDBC3PreparedStatement.java:57)
    at Gui.accounts$3.actionPerformed(accounts.java:136)
    at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
    at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
    at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
    at java.awt.Component.processMouseEvent(Unknown Source)
    at javax.swing.JComponent.processMouseEvent(Unknown Source)
    at java.awt.Component.processEvent(Unknown Source)
    at java.awt.Container.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
    at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Window.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

我无法弄清楚什么是错的。在遇到类似问题之前见过几个人，但没有任何帮助。

提前致谢

Answer 1

查看allItems的来源。

我怀疑发生的事情如下：

你做net.proteanit.sql.DbUtils
table_1.setModel(DbUtils.resultSetToTableModel(rs));保存对resultSetToTableModel的引用，但希望它保持有效，以便可以延迟加载数据。
当控件退出ResultSet时，try和PreparedStatement都会超出范围。出于某种原因，ResultSet正在收集垃圾（可能PreparedStatement中只有弱引用？）

您可能应该在顶级声明ResultSet和PreparedStatement，这样它们就不会超出范围。

java.sql.SQLException：准备好的语句已经完成

1 个答案: