jsp中List,ArrayList的使用方法，jsparraylist

public static List getPageUser(int currentPage) throws Exception {//?List
         Connection conn = null;
         PreparedStatement prep = null;
         ResultSet rs = null;
         List result = new ArrayList();// 接口 List<E>， 此接口的用户可以对列表中每个元素的插入位置进行精确地控制。用户可以根据元素的整数索引（在列表中的位置）访问元素，并搜索列表中的元素。
public class ArrayList<E>extends AbstractList<E>implements List<E>, RandomAccess, Cloneable,SerializableList 接口的大小可变数组的实现。实现了所有可选列表操作，并允许包括 null 在内的所有元素。除了实现 List 接口外，此类还提供一些方法来操作内部用来存储列表的数组的大小。

         try {
             conn = new DBConnection().getConnection();
             int rowCount = getCount();//返回用户总数
             int pageSize = getPageSize();//
             //应获取的记录数
             int rows = (rowCount - (currentPage - 1) * getPageSize()) >
                        getPageSize() ?
                        pageSize : (rowCount - (currentPage - 1) * getPageSize());
                        //用户总数-（当前页号-1）*固定页大小〉页大小？正常页 大小：用户总数-（当前页号-1）*固定页大小//
             //分页的查询语句??????????????????????????????????
                        String sql = " SELECT TOP " + rows + " * FROM" +
                          " (SELECT TOP " + currentPage * getPageSize() +
                          " * FROM [Testuser] Order by id asc) a" +
                          " order by id desc";
                        
//                      // String sql = " SELECT TOP"+ rows + " * FROM Testuser WHERE (id NOT IN"
//                     //+"(SELECT TOP"+ rows*getPageSize()+"id FROM Testuser "
//                       // +"ORDER BY id))"
//                      // +"ORDER BY ID" ;

             System.out.println("sql:" + sql);
             //out.println(str);
             prep = conn.prepareStatement(sql);
             rs = prep.executeQuery();
     
             while (rs.next()) {
                 UserBean user = new UserBean();
                 user.setId(rs.getInt(1));
                 user.setLoginName(rs.getString(2));
                 user.setPassword(rs.getString(3));
                 user.setBirthday(rs.getString(4));
                 user.setScore(rs.getString(5));
                 user.setAddress(rs.getString(6));
                
                 result.add(user);
             }

         } finally {
             if (rs != null) {
                 rs.close();
             }
             if (prep != null) {
                 prep.close();
             }
             if (conn != null) {
                 conn.close();
             }
         }
         return result;

     }
建立可变数组对象:List result= new ArrayList();
将结果保存到ResultSet 对象rs中
利用rs.next()方法将rs中的搜索结果逐条保存到UserBean的对象user中，然后利用ArrayList类中的add()方法将user添加到ArrayList对象 result 中：
while (rs.next()) {
                 UserBean user = new UserBean();
                 user.setId(rs.getInt(1));
                 user.setLoginName(rs.getString(2));
                 user.setPassword(rs.getString(3));
                 user.setBirthday(rs.getString(4));
                 user.setScore(rs.getString(5));
                 user.setAddress(rs.getString(6));
                
                 result.add(user);
方法getPageUser(int currentPage)返回的是ArrayList对象，该对象中包含了许多UserBean对象，UserBean对象中存储着搜索结果；通过ArrayList累得个get(int number)方法可返回其中的元素：
                 List students = User.getPageUser(curPage);
for (; i < students.size(); i++) {
UserBean studentBean = (UserBean) students.get(i);
        out.println("<td><input type='checkbox' name='chkStudent' value="+studentBean.getId()+"></td>");

out.println("<td align=center>" + studentBean.getId()+ "</td>");
      }