使用Struts2框架完成一个简单的留言板（包含完整源代码+数据库+程序截图+中文显示数据）

package com.dao; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import javax.swing.JOptionPane; import com.bean.Message; public class DBManager { public static Connection conn; public static Statement stmt; // 注册 public static int addUser(String userName, String password) { String sql = "insert into Users values('" + userName + "','" + password + "')"; int result = executeNonQuery(sql); return result; } // 登录 public static boolean canLogin(String userName, String password) { String sql = "select * from Users where userName='" + userName + "' and password='" + password + "'"; ResultSet rs = executeQuery(sql); try { while (rs.next()) { return true; } } catch (SQLException e) { e.printStackTrace(); } return false; } // 查询所有留言 public static ArrayList<Message> queryAllMessages(String username) throws Exception { ArrayList<Message> messages = new ArrayList<Message>(); String sql = "select * from message where userName='" + username + "'"; ResultSet rs = executeQuery(sql); while (rs.next()) { Message message = new Message(); message.setId(rs.getString("id")); message.setTitle(rs.getString("title")); message.setContent(rs.getString("content")); message.setDate(rs.getString("date")); message.setUserName(rs.getString("userName")); messages.add(message); } Close(); return messages; } // 查询编号所对应的留言 public static Message queryMessageInfoById(String id) throws Exception { String sql = "select * from message where id ='" + id + "'"; ResultSet rs = executeQuery(sql); Message message = new Message(); while (rs.next()) { message.setId(rs.getString("id")); message.setTitle(rs.getString("title")); message.setContent(rs.getString("content")); message.setDate(rs.getString("date")); message.setUserName(rs.getString("userName")); } Close(); return message; } // 修改一条留言 public static void alterMessage(String content, String date, String id) throws SQLException { String sql = "update message set content='" + content + "',date='" + date + "' where id='" + id + "'"; int result = executeNonQuery(sql); } // 添加一条留言 public static void addMessage(String tilte, String content, String date, String username) throws SQLException { String sql = "insert into message values('" + tilte + "','" + content + "','" + date + "','" + username + "')"; int result = executeNonQuery(sql); } // 删除一条留言 public static int deleteMessage(String id) throws SQLException { String sql = "delete from message where id='" + id + "'"; int result = executeNonQuery(sql); return result; } public static void getcon() { String url = "jdbc:odbc:MessageBoard"; String user = "sa"; String pwd = "123"; try { // 加载驱动程序 Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); // 创建连接 conn = DriverManager.getConnection(url, user, pwd); } catch (ClassNotFoundException e) { JOptionPane.showMessageDialog(null, "加载驱动程序出错!", "警告", JOptionPane.WARNING_MESSAGE); } catch (SQLException e) { JOptionPane.showMessageDialog(null, e.getMessage(), "警告", JOptionPane.WARNING_MESSAGE); } catch (Exception e) { JOptionPane.showMessageDialog(null, "不能建立连接！", "警告", JOptionPane.WARNING_MESSAGE); } } public static int executeNonQuery(String SQL) { try { getcon(); stmt = conn.createStatement(); return stmt.executeUpdate(SQL); } catch (SQLException e) { JOptionPane.showMessageDialog(null, "数据库操作失败!", "警告", JOptionPane.WARNING_MESSAGE); } return 0; } public static ResultSet executeQuery(String SQL) { try { getcon(); stmt = conn.createStatement(); ResultSet rs = stmt.executeQuery(SQL); return rs; } catch (SQLException e) { JOptionPane.showMessageDialog(null, "查询失败!", "警告", JOptionPane.WARNING_MESSAGE); } return null; } public static void Close() { try { if (stmt != null) stmt.close(); if (conn != null) conn.close(); } catch (SQLException e) { JOptionPane.showMessageDialog(null, "不能正常关闭!", "警告", JOptionPane.WARNING_MESSAGE); } } }