jsp+servlet+javabean图形打印器

package DAO; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import javax.naming.Context; import javax.naming.InitialContext; import javax.naming.NamingException; import javax.sql.DataSource; import Print.PrintBean; public class PrintModel { private Connection con; //连接语句 private PreparedStatement ps; //预处理语句 private ResultSet rs; //查询结果集 public List getStyles() { List printlist=new ArrayList(); /* * JNDI用法 */ try { Context ic=new InitialContext(); DataSource ds=(DataSource)ic.lookup("java:comp/env/jdbc/Print"); con=ds.getConnection(); ps=con.prepareStatement("select * from shapeInfo"); rs =ps.executeQuery(); while(rs.next()) { PrintBean pb=new PrintBean(); pb.setShapeID(rs.getString("shapeID")); pb.setShapeStyle(rs.getString("shapeStyle")); printlist.add(pb); } } catch (NamingException e) { e.printStackTrace(); System.out.println(e); } catch (SQLException e) { e.printStackTrace(); System.out.println(e); } return printlist; } public static void CloseConnction(Connection con) { try { if(con !=null && !con.isClosed()) { con.close(); } } catch (SQLException e) { e.printStackTrace(); System.out.println(e); } } /* * 关闭结果集的方法 */ public static void CloseResultSet(ResultSet res) { try { if(res !=null) { res.close(); res=null; } } catch (SQLException e) { e.printStackTrace(); System.out.println(e); } } /* * 关闭SQL语句的方法 */ public static void CloseStatement(PreparedStatement pstate) { try { if(pstate !=null) { pstate.close(); pstate.close(); } } catch (SQLException e) { e.printStackTrace(); System.out.println(e); } } }