showallinfo.java

一个简单的学生信息查询系统

//ShowAllInfo.java 

import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 
import javax.swing.table.*; 
import java.util.*; 
import java.sql.*; 

public class ShowAllInfo extends JFrame implements ActionListener { 
    JPanel contentPane; 

    JButton b_first, b_pre, b_next, b_last; 

    JLabel label_1, label_2; 

    Vector vector; 

    JTextField text; 

    String[] title = { "学号", "姓名", "性别", "出生日期", "所属班级", "家庭地址", "手机", "入学时间", "毕业时间", "文凭" }; 

    Connection con = null; 

    Statement stmt = null; 

    ResultSet rs = null; 

    AbstractTableModel tm; 

    String sql; 

    int pagenum = 0; 

    int lastpagenum; 

    int t; 

    int everypagenumber = 10; 

    public ShowAllInfo() { 
        super("显示所有学生信息"); 
        contentPane = (JPanel) this.getContentPane(); 
        contentPane.setLayout(null); 
        setSize(555, 417); 

        b_first = new JButton("首页"); 
        b_pre = new JButton("上页"); 
        b_next = new JButton("下页"); 
        b_last = new JButton("尾页"); 

        label_1 = new JLabel("第"); 
        label_2 = new JLabel("页"); 

        text = new JTextField(); 

        contentPane.add(b_first); 
        b_first.setBounds(30, 297, 77, 39); 
        contentPane.add(b_pre); 
        b_pre.setBounds(135, 297, 77, 39); 
        contentPane.add(b_next); 
        b_next.setBounds(240, 297, 77, 39); 
        contentPane.add(b_last); 
        b_last.setBounds(345, 297, 77, 39); 
        contentPane.add(label_1); 
        label_1.setBounds(373, 349, 22, 24); 
        contentPane.add(label_2); 
        label_2.setBounds(428, 349, 22, 34); 
        contentPane.add(text); 
        text.setBounds(392, 352, 30, 19); 

        b_first.addActionListener(this); 
        b_pre.addActionListener(this); 
        b_next.addActionListener(this); 
        b_last.addActionListener(this); 

        // 将窗口置于屏幕中央 
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); 
        Dimension frameSize = this.getSize(); 
        if (frameSize.height > screenSize.height) { 
            frameSize.height = screenSize.height; 
        } 
        if (frameSize.width > screenSize.width) { 
            frameSize.width = screenSize.width; 
        } 
        setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2); 
        setResizable(false); 
        setVisible(true); 
        createtable(); 
    } 

    void createtable() { 
        //JTable table; 
        JScrollPane scroll; 
        vector = new Vector(); 
        tm = new AbstractTableModel() { 
            public int getColumnCount() { 
                return title.length; 
            } 

            public int getRowCount() { 
                return vector.size(); 
            } 

            public Object getValueAt(int row, int column) { 
                if (!vector.isEmpty()) { 
                    return ((Vector) vector.elementAt(row)).elementAt(column); 
                } else { 
                    return null; 
                } 
            } 

            public void setValueAt(Object value, int row, int column) { 
            } 

            public String getColumnName(int column) { 
                return title[column]; 
            } 

            public Class getColumnClass(int c) { 
                return getValueAt(0, c).getClass(); 
            } 

            public boolean isCellEditable(int row, int cloumn) { 
                return false; 
            } 
        };
        //table = new JTable;
        JTable table = new JTable();
        table.setToolTipText("显示查询结果"); 
        table.setAutoResizeMode(table.AUTO_RESIZE_OFF); 
        table.setCellSelectionEnabled(false); 
        table.setShowHorizontalLines(true); 
        table.setShowVerticalLines(true); 
        scroll = new JScrollPane(table); 
        contentPane.add(scroll); 
        scroll.setBounds(6, 20, 540, 250); 
        firstrun(); 
    } 

    public void actionPerformed(ActionEvent e) { 
        if (e.getSource() == b_first) { 
            firstrun(); 
        } else if (e.getSource() == b_pre) { 
            try { 
                pagenum--; 
                if (pagenum <= 0) { 
                    pagenum++; 
                    JOptionPane.showMessageDialog(null, "已经到达首页", "警告", JOptionPane.WARNING_MESSAGE); 
                } 
                Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); 
                String url = "jdbc:microsoft:sqlserver://localhost:1433;User=sa;Password=;DatabaseName=student"; 
                con = DriverManager.getConnection(url); 
                stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE); 
                sql = "select * from StudentInfo"; 
                rs = stmt.executeQuery(sql); 
                String displaypage = pagenum + "/" + lastpagenum; 
                text.setText(displaypage); 
                vector.removeAllElements(); 
                tm.fireTableStructureChanged(); 
                for (int i = 1; i <= (pagenum - 1) * everypagenumber; i++) { 
                    rs.next(); 
                } 
                for (int i = pagenum * everypagenumber + 1; i <= (pagenum + 1) * everypagenumber; i++) { 
                    if (rs.next()) { 
                        Vector rec_vector = new Vector(); 
                        for (int j = 1; j <= title.length; j++) { 
                            rec_vector.addElement(rs.getString(j)); 
                        } 
                        vector.addElement(rec_vector); 
                    } 
                } 
                tm.fireTableStructureChanged(); 
                } catch (SQLException ex) { 
                    System.out.println("上页错误" + ex); 
                } catch (ClassNotFoundException ex) { 
                    System.out.println("数据库连接错误" + ex); 
                } finally { 
                    try { 
                        if (rs != null) { 
                            rs.close(); 
                        } 
                        if (stmt != null) { 
                            stmt.close(); 
                        } 
                        if (con != null) { 
                            con.close(); 
                        } 
                    } catch (Exception ex) { 
                    } 
                } 

            } else if (e.getSource() == b_next) { 
                try { 
                    pagenum++; 
                    if (pagenum > lastpagenum) { 
                        pagenum--; 
                        JOptionPane.showMessageDialog(null, "已经到达尾页", "警告", JOptionPane.WARNING_MESSAGE); 
                } 
                Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); 
                String url = "jdbc:microsoft:sqlserver://localhost:1433;User=sa;Password=;DatabaseName=student"; 
                con = DriverManager.getConnection(url); 
                stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE); 
                sql = "select * from StudentInfo"; 
                rs = stmt.executeQuery(sql); 
                String displaypage = pagenum + "/" + lastpagenum; 
                text.setText(displaypage); 
                vector.removeAllElements(); 
                tm.fireTableStructureChanged(); 
                for (int i = 1; i <= (pagenum - 1) * everypagenumber; i++) { 
                    rs.next(); 
                } 
                for (int i = (pagenum - 1) * everypagenumber + 1; i <= pagenum * everypagenumber; i++) { 
                    if (rs.next()) { 
                        Vector rec_vector = new Vector(); 
                        for (int j = 1; j <= title.length; j++) { 
                            rec_vector.addElement(rs.getString(j)); 
                        } 
                        vector.addElement(rec_vector); 
                    } 
                } 
                tm.fireTableStructureChanged(); 
                } catch (SQLException ex) { 
                    System.out.println("下页错误" + ex); 
                } catch (ClassNotFoundException ex) { 
                    System.out.println("数据库连接错误" + ex); 
                } finally { 
                     try { 
                         if (rs != null) { 
                             rs.close(); 
                         } 
                         if (stmt != null) { 
                             stmt.close(); 
                         } 
                         if (con != null) { 
                             con.close(); 
                         } 
                     } catch (Exception ex) { 
                     } 
                 } 

             } else if (e.getSource() == b_last) { 
                 try { 
                     Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); 
                     String url = "jdbc:microsoft:sqlserver://localhost:1433;User=sa;Password=;DatabaseName=student"; 
                     con = DriverManager.getConnection(url); 
                     stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE); 
                     sql = "select * from StudentInfo"; 
                     int recordnum = 0; 
                     rs = stmt.executeQuery(sql); 
                     while (rs.next()) { 
                         recordnum++; 
                     } 
                     int t = recordnum % everypagenumber; 
                     if (t != 0) { 
                         lastpagenum = recordnum / everypagenumber + 1; 
                     } else { 
                         lastpagenum = recordnum / everypagenumber; 
                     } 
                     String displaypage = pagenum + "/" + lastpagenum; 
                     text.setText(displaypage); 
                     int displaynum = (recordnum % everypagenumber); 
                     if (displaynum == 0) { 
                         displaynum = everypagenumber; 
                     } 
                     vector.removeAllElements(); 
                     tm.fireTableStructureChanged(); 
                     for (int i = 0; i <= displaynum; i++) { 
                         rs.previous(); 
                     } 
                     for (int i = 1; i <= displaynum; i++) { 
                         if (rs.next()) { 
                             Vector rec_vector = new Vector(); 
                             for (int j = 1; j <= title.length; j++) { 
                                 rec_vector.addElement(rs.getString(j)); 
                             } 
                             vector.addElement(rec_vector); 
                         } 
                     } 
                     tm.fireTableStructureChanged(); 
                     } catch (SQLException ex) { 
                         System.out.println("首页错误" + ex); 
                     } catch (ClassNotFoundException ex) { 
                         System.out.println("数据库连接错误" + ex); 
                     } finally { 
                         try { 
                             if (rs != null) { 
                                 rs.close(); 
                             } 
                             if (stmt != null) { 
                                 stmt.close(); 
                             } 
                             if (con != null) { 
                                 con.close(); 
                             } 
                         } catch (Exception ex) { 
                         } 
                     } 

                 } 
            } 

            void firstrun() { 
                try { 
                    pagenum = 1; 
                    int recordnum = 0; 
                    Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver"); 
                    String url = "jdbc:microsoft:sqlserver://localhost:1433;User=sa;Password=;DatabaseName=student"; 
                    con = DriverManager.getConnection(url); 
                    stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE); 
                    sql = "select * from StudentInfo"; 
                    rs = stmt.executeQuery(sql); 
                    while (rs.next()) { 
                    recordnum++; 
                } 
                int t = recordnum % everypagenumber; 
                if (t != 0) { 
                    lastpagenum = recordnum / everypagenumber + 1; 
                } else { 
                    lastpagenum = recordnum / everypagenumber; 
                } 
                rs.beforeFirst(); 
                String displaypage = pagenum + "/" + lastpagenum; 
                text.setText(displaypage); 
                vector.removeAllElements(); 
                tm.fireTableStructureChanged(); 
                for (int i = 1; i <= everypagenumber; i++) { 
                    if (rs.next()) { 
                        Vector rec_vector = new Vector(); 
                        for (int j = 1; j <= title.length; j++) { 
                            rec_vector.addElement(rs.getString(j)); 
                        } 
                        vector.addElement(rec_vector); 
                    } 
                } 
                tm.fireTableStructureChanged(); 
                } catch (SQLException ex) { 
                    System.out.println("首页错误" + ex); 
                } catch (ClassNotFoundException ex) { 
                    System.out.println("数据库连接错误" + ex); 
                } finally { 
                    try { 
                        if (rs != null) { 
                            rs.close(); 
                        } 
                        if (stmt != null) { 
                            stmt.close(); 
                        } 
                        if (con != null) { 
                            con.close(); 
                        } 
                    } catch (Exception ex) { 
                    } 
                } 
            } 
}