jsp+mysql实现增删改查的简单例子

package db; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.sql.DriverManager; import java.util.ArrayList; public class ConnDb { private static Connection con = null; private static Statement stmt = null; private static ResultSet rs = null; public static void startconn() { // 连接数据库 try { Class.forName("com.mysql.jdbc.Driver"); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { con = DriverManager.getConnection( "jdbc:mysql://localhost:3306/test?characterEncoding=utf-8", "root", "root"); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void endconn() throws SQLException { // 关闭连接 if (rs != null) { rs.close(); rs = null; } if (stmt != null) { stmt.close(); stmt = null; } if (con != null) { con.close(); con = null; } } public static void update(String sql) throws SQLException { startconn(); stmt = con.createStatement(); stmt.executeUpdate(sql); endconn(); } public static ArrayList<Student> getList1(String sql) throws SQLException { ArrayList<Student> list = new ArrayList<Student>(); startconn(); stmt = con.createStatement(); rs = stmt.executeQuery(sql); while (rs.next()) { Student st = new Student(); st.setSid(rs.getString("sid")); st.setName(rs.getString("sname")); st.setAge(rs.getString("sage")); list.add(st); } endconn(); return list; } }