实现pageHalper分页

弄了一小时总算弄出来的，记一下省着忘，以后直接copy着用就可以了，哈哈

首先：创建pageHalperUtil

public class pageHalperUtil {

    private Integer firstPage;
    private Integer lastPage;
    private Integer pageNum;
    private List list;
          。。。。。。。  （封装省略）   
}

其次：编写service层

public pageHalperUtil getList(Integer pageNum,Integer pageSize) {
        TOrderExample example = new TOrderExample();
        PageHelper.startPage(pageNum, pageSize);
        List<TOrder> list = orderMapper.selectByExample(example);
        PageInfo<TOrder> pageInfo = new PageInfo<TOrder>(list);
        pageHalperUtil pageHalperUtil = new pageHalperUtil();
        pageHalperUtil.setFirstPage(pageInfo.getFirstPage());
        pageHalperUtil.setLastPage(pageInfo.getLastPage());
        pageHalperUtil.setPageNum(pageInfo.getPageNum());
        pageHalperUtil.setList(pageInfo.getList());
        return pageHalperUtil;
}

然后：编写controller层

@RequestMapping("list")
    public ModelAndView list(@RequestParam(value="page", defaultValue="1")Integer pageNum) {
        Integer pageSize = 3;
        pageHalperUtil result = orderService.getList2(pageNum, pageSize);
        ModelAndView mv = new ModelAndView();
        mv.addObject("firstPage", result.getFirstPage());
        mv.addObject("lastPage", result.getLastPage());
        mv.addObject("pageNum", result.getPageNum());
        mv.addObject("list", result.getList());
        mv.setViewName("order_list");
        return mv;
}

最后：jsp页面

<!-- pages==lastPage 所以用lastPage代替 --> 
        <tr>
            <td colspan="5" align="center">  
                <c:if test="${pageNum != 1}">  
                    <a href="list.do?page=${pageNum - 1}">上一页</a>  
                </c:if>  
                <c:if test="${lastPage != 1}">
                    <c:forEach var="pageIndex" begin="1" end="${lastPage}">  
                        <c:choose>
                            <c:when test="${pageNum == pageIndex}">  
                                <a>${pageIndex}</a>  
                            </c:when>  
                            <c:otherwise>  
                                <a href="list.do?page=${pageIndex}">${pageIndex}</a>  
                            </c:otherwise>  
                        </c:choose>  
                    </c:forEach>  
                </c:if>  
                <c:if test="${pageNum != lastPage}">  
                    <a href="list.do?page=${pageNum+1}">下一页</a>  
                </c:if>  
            </td>
        </tr>