用各种标签做的一个JSP分页项目

package com.njtysoft.page.dao; import java.sql.*; import java.util.ArrayList; import java.util.List; import com.njtysoft.page.dto.User; public class UserDAO { private Connection conn = null; private PreparedStatement ps = null; private ResultSet rs = null; private Connection getConn() { //此连接mysql数据库 try { Class.forName("com.mysql.jdbc.Driver"); return DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "root", "pass"); }catch(Exception ex) { ex.printStackTrace(); } return null; } private String getSql(String name) { //整理SQL语句 String[] strr = name.trim().split(" "); String sql = "select * from help_keyword where name like \'%" + strr[0] + "%\'"; for(int i = 1; i < strr.length; i++) { if(strr[i].equals("")) { continue; } sql = (new StringBuilder()).append(sql).append(" or name like \'%" + strr[i] + "%\'").toString(); } return sql; } //获得需要向前台显示的数据集 public List<User> getUsersByLikeName(String name, int currentPage, int pageSize) { List<User> users = new ArrayList<User>(); String sql = this.getSql(name); int rowStart = (currentPage - 1) * pageSize; sql = sql + " limit " + rowStart + ", " + pageSize; //每次只获得一页的数据 try { conn = this.getConn(); ps = conn.prepareStatement(sql); rs = ps.executeQuery(); while(rs.next()) { int id = rs.getInt("help_keyword_id"); String mname = rs.getString("name"); User user = new User(id, mname); users.add(user); } return users; }catch(Exception ex) { ex.printStackTrace(); }finally { this.close(); } return null; } //获得符合查询条件的总记录数 public int getAllRows(String name) { int allRows = 0; String sql = this.getSql(name); try { conn = this.getConn(); ps = conn.prepareStatement(sql); rs = ps.executeQuery(); while(rs.next()) { allRows ++; } return allRows; }catch(Exception ex) { ex.printStackTrace(); }finally { this.close(); } return 0; } private void close() { try { if(rs != null) { rs.close(); } if(ps != null) { ps.close(); } if(conn != null) { conn.close(); } }catch(Exception ex) { ex.printStackTrace(); } } }