從controller到mapper.xml的后端實現
只梳理分頁相關代碼
1 controller里面相關
ModelAndView mv = new ModelAndView("/listDesc/listingDescPage");
int pageSize = 2;
List<ListingDesc> dataDto = new ArrayList<ListingDesc>();
List<ListingDesc> totalList;
ListingDescServiceClient listingDescServiceClient = ItemTools
.getListingDescServiceClient();
// 獲取總記錄數，准備分頁
totalList = listingDescServiceClient
.findListingDescByIListingDesc(listingDesc);
// 分頁工具
PaginationList<ListingDesc> pageMode = new PaginationList<ListingDesc>();
pageMode.setPageIndex(currentPage);
pageMode.setPageSize(pageSize);
dataDto = listingDescServiceClient.findListingByCondition(
listingDesc, pageMode);
log.info("共查詢出》》》》" + totalList.size() + "條數據");
this.getPage(request, pageSize, totalList.size());
private int getPage(HttpServletRequest request, Integer recordPageCount,
Integer totalCount) {
request.setAttribute("totalPageCount", totalPageCount);
request.setAttribute("totalCount", totalCount);
request.setAttribute("pageSize", 2);
return startNum;}
getpage()方法里面只需把三個參數總頁數，當前頁，每頁顯示條數封裝進request即可，我這當前頁在別的地方已封裝過所以此處沒封裝，在此處封裝了記錄總條數，其實在自定義標簽里是用不到的。
2 service
List<ListingDesc> list = null;
try{
if(listingDesc!= null){
//獲取總記錄數
int totalRecordCount = listingDescService.findListingDescByListingDesc(listingDesc).size();
pageMode.setTotalRecords(totalRecordCount);
//計算每頁起始記錄
int firstresult = (pageMode.getPageIndex()-1)*pageMode.getPageSize();
list =listingDescService.findListingByCondition(listingDesc, firstresult, pageMode.getPageSize());
logger.info("ListingDescServiceClient:findListingByCondition method end=====returnList is "+ list);
}else{
logger.info("ListingDescServiceClient:findListingByCondition method end=====params listingDesc is null.");
return null;
}
}catch(Exception e){
e.getStackTrace();
}
return (PaginationList<ListingDesc>)list;
我用的是ejb架構，在此和ssm架構稍有不同，這段代碼直接拿到service下改造一下即可
3 dao相關
// 根據listingDesc,firstResult,maxResult查找並分頁
@Override
public PaginationList<ListingDesc> findListingByCondition(
ListingDesc listingDesc, int firstResult, int maxResults) {
return listingDescDao.findListingByCondition(listingDesc, firstResult,
maxResults);
}
@Override
public PaginationList<ListingDesc> findListingByCondition(
ListingDesc listingDesc, int firstResult, int maxResults) {
return (PaginationList<ListingDesc>) this.findByExampleForPage(
"findListingDescByCondition", listingDesc, firstResult,
maxResults);
}
public abstract class BaseDao<T, PK> implements IDao<T, PK> {
@Autowired
private SqlSessionTemplate sqlSession;
*/
protected PaginationList findByExampleForPage(String sqlId, Object param, int firstResult, int maxResults) {
UleRowBounds rowBounds = new UleRowBounds(firstResult, maxResults, UleRowBounds.TYPE_PAGE_SELECT);
return (PaginationList) sqlSession.selectList(this.getClass().getName() + "." + sqlId, param, rowBounds);
}
4 mapper
<select id="findListingDescByCondition" resultType="ListingDesc"
parameterType="ListingDesc">
SELECT
SEQ_ID seqId,
LIST_ID listId,
DESC_NAME descName,
DESC_VALUE
descValue,
SORT_NUM sortNum,
DEL_FLAG delFlag,
CREATE_TIME createTime,
UPDATE_TIME updateTime
FROM LISTING_DESC
<where>
<if test="seqId != null"> SEQ_ID = #{seqId}</if>
<if test="listId != null"> AND LIST_ID = #{listId}</if>
<if test="descName != null and descName != ''"> AND DESC_NAME = #{descName}</if>
</where>
</select>
至此分頁后端完成，關於dao層的mybatis實現自己可以查看一些相關資料。主要是dao實現類繼承baseDao:
@Repository
public class ListingDescDaoImpl extends BaseDao<ListingDesc, Long> implements ListingDescDao
然后baseDao實現IDao接口
public abstract class BaseDao<T, PK> implements IDao<T, PK> {
@Autowired
private SqlSessionTemplate sqlSession;
里面可以用 SqlSessionTemplate sqlSession的api實現相關增刪改查。
這是Idao里關於分頁的內容：
public interface IDao<T, PK> {
/**
* 分頁查詢數據，返回分頁結構對象PaginationList，該方法包含兩次SQL查詢，一次查詢數據，一次統計總結果數
* @param t 查詢參數對象
* @param firstResult 查詢結果第一次記錄的偏移量，表示從第幾條數據開始返回
* @param maxResults 返回結果集大小
* @return
*/
public PaginationList findByExampleForPage(T t, int firstResult, int maxResults);
/**
* 分頁查詢數據，返回分頁結構對象PaginationList，該方法包含兩次SQL查詢，一次查詢數據，一次統計總結果數
* @param t 查詢參數對象
* @param firstResult 查詢結果第一次記錄的偏移量，表示從第幾條數據開始返回
* @param maxResults 返回結果集大小
* @param orders SQL排序子串
* @return
*/
public PaginationList findByExampleForPage(T t, int firstResult, int maxResults, Order... orders);
public static class Order{
private boolean ascending;
private String propertyName;
public String toString() {
return propertyName + ' ' + (ascending?"asc":"desc");
}
protected Order(String propertyName, boolean ascending) {
this.propertyName = propertyName;
this.ascending = ascending;
}
public static Order asc(String propertyName) {
return new Order(propertyName, true);
}
public static Order desc(String propertyName) {
return new Order(propertyName, false);
}
}
}