www.pudn.com > students.rar > UserDAO.java

package students; 
import java.sql.*; 
public class UserDAO { 
	static User user = new User(); 
	public static ResultSet queryUserByUsername(String username){ 
		 
 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		try { 
			con = Database.connectToDb(); 
			String strSQL = "select * from students where ID = '"+username+"'"; 
			stmt = con.createStatement(); 
			rs = stmt.executeQuery(strSQL); 
			 
		} catch (SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} 
		 
		return rs; 
	} 
	public static void AddUser(String stuid,String password, String name,  
			String sex, String enrollage, String enrollyear, String class1) { 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		 
		try { 
			con = Database.connectToDb(); 
			String strSQL = "insert into students(ID,password,name,sex,enrollage,enrollyear,Class)"+"values('"+stuid+"','"+password+"','"+name+"','"+sex+"','"+enrollage+"','"+enrollyear+"','"+class1+"')"; 
			stmt = con.createStatement(); 
			stmt.executeUpdate(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} finally { 
			if (con != null) { 
				try { 
					con.close(); 
				} catch (SQLException e) { 
					e.printStackTrace(); 
				} 
				con = null; 
			} 
		} 
	} 
	public static void Delete(String stuid){ 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		try { 
			con = Database.connectToDb(); 
			String strSQL="delete from students where ID='"+stuid+"'"; 
			stmt = con.createStatement(); 
			 
			stmt.executeUpdate(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} finally { 
			if (con != null) { 
				try { 
					con.close(); 
				} catch (SQLException e) { 
					e.printStackTrace(); 
				} 
				con = null; 
			} 
		} 
	} 
	public static void AddCrouse(String cro_id,String cro_name,String cro_teacher,String cro_value,String cro_grade,String cro_dropyear){ 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		 
		try { 
			con = Database.connectToDb(); 
			String strSQL = "insert into crouses(cro_id, cro_name, cro_teacher, cro_value, cro_grade, cro_dropyear)"+"values('"+cro_id+"','"+cro_name+"','"+cro_teacher+"','"+cro_value+"','"+cro_grade+"','"+cro_dropyear+"')"; 
			stmt = con.createStatement(); 
			stmt.executeUpdate(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} finally { 
			if (con != null) { 
				try { 
					con.close(); 
				} catch (SQLException e) { 
					e.printStackTrace(); 
				} 
				con = null; 
			} 
		} 
	} 
	public static void DeleteCrouse(String cro_id){ 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		try { 
			con = Database.connectToDb(); 
			String strSQL="delete from crouses where cro_id='"+cro_id+"'";  
			stmt = con.createStatement(); 
			 
			stmt.executeUpdate(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} finally { 
			if (con != null) { 
				try { 
					con.close(); 
				} catch (SQLException e) { 
					e.printStackTrace(); 
				} 
				con = null; 
			} 
		} 
	} 
	public static ResultSet select(String sql){ 
		Connection con = null; 
		Statement stmt = null; 
		ResultSet rs = null; 
		 
		try { 
			con = Database.connectToDb(); 
			String strSQL = sql; 
			stmt = con.createStatement(); 
			rs = stmt.executeQuery(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		 
		} 
		return rs; 
	} 
	public static void update(String sql){ 
		Connection con = null; 
		Statement stmt = null; 
		 
		 
		try { 
			con = Database.connectToDb(); 
			String strSQL = sql; 
			stmt = con.createStatement(); 
			stmt.executeUpdate(strSQL); 
		}catch(SQLException e) { 
			e.printStackTrace(); 
		} catch (Exception e) { 
			e.printStackTrace(); 
		} finally { 
			if (con != null) { 
				try { 
					con.close(); 
				} catch (SQLException e) { 
					e.printStackTrace(); 
				} 
				con = null; 
			} 
		} 
		 
	} 
}