// ===================================================================================
// isNecessaryToReadPageAgain()
// ============================
public void test_isNecessaryToReadPageAgain() {
// ## Arrange ##
List<String> selectedList = new ArrayList<String>();
PagingResultBean<String> rb = new PagingResultBean<String>();
rb.setSelectedList(selectedList);
PagingInvoker<String> tgt = createTarget();
// ## Act & Assert ##
rb.setAllRecordCount(0);
assertFalse(tgt.isNecessaryToReadPageAgain(rb));
rb.setAllRecordCount(1);
assertTrue(tgt.isNecessaryToReadPageAgain(rb));
selectedList.add("one");
assertFalse(tgt.isNecessaryToReadPageAgain(rb));
rb.setAllRecordCount(0);
assertFalse(tgt.isNecessaryToReadPageAgain(rb));
}
public void test_invokePaging_threePageCurrent_countLater_just() {
// ## Arrange ##
final List<String> selectedList = new ArrayList<String>();
fillList(selectedList, 20);
final SimplePagingBean pagingBean =
new SimplePagingBean() {
@Override
public boolean canPagingCountLater() {
return true;
}
};
pagingBean.getSqlClause().registerOrderBy("aaa", true, new MockColumnInfo());
pagingBean.fetchFirst(20);
pagingBean.fetchPage(3);
PagingInvoker<String> tgt = createTarget();
// ## Act ##
final List<String> markList = new ArrayList<String>();
PagingResultBean<String> rb =
tgt.invokePaging(
new PagingHandler<String>() {
public PagingBean getPagingBean() {
return pagingBean;
}
public int count() {
markList.add("count");
return 60;
}
public List<String> paging() {
markList.add("paging");
return selectedList;
}
});
// ## Assert ##
assertEquals(20, rb.size());
assertEquals(60, rb.getAllRecordCount());
assertEquals(3, rb.getAllPageCount());
assertEquals(1, rb.getOrderByClause().getOrderByList().size());
assertEquals("paging", markList.get(0));
assertEquals("count", markList.get(1));
}
// ===================================================================================
// invokePaging()
// ==============
public void test_invokePaging_emtpy() {
// ## Arrange ##
final List<String> selectedList = new ArrayList<String>();
final SimplePagingBean pagingBean = new SimplePagingBean();
pagingBean.getSqlClause().registerOrderBy("aaa", true, new MockColumnInfo());
pagingBean.fetchFirst(20);
PagingInvoker<String> tgt = createTarget();
// ## Act ##
final List<String> markList = new ArrayList<String>();
PagingResultBean<String> rb =
tgt.invokePaging(
new PagingHandler<String>() {
public PagingBean getPagingBean() {
return pagingBean;
}
public int count() {
markList.add("count");
return 0;
}
public List<String> paging() {
markList.add("paging");
return selectedList;
}
});
// ## Assert ##
assertEquals(0, rb.size());
assertEquals(0, rb.getAllRecordCount());
assertEquals(1, rb.getAllPageCount());
assertEquals(1, rb.getOrderByClause().getOrderByList().size());
assertEquals("count", markList.get(0));
assertEquals(1, markList.size());
}
/**
* 依設定執行多階段分頁
*
* @param <T> 回傳的 List Generic Type
* @param filter 實作取得資料的 Closure
* @param resultBean 分頁的資料物件
* @param fetchPhase 要執行的階段
* @return 可能為 Empty List 的結果
* @see #runTwoPhasePagingFilter(TwoPhasePagingFilter, PagingResultBean)
*/
public static <T> List<T> runTwoPhasePagingFilter(
TwoPhasePagingFilter<T> filter, PagingResultBean resultBean, FetchPhase fetchPhase) {
checkValidPagingResultBean(resultBean);
fetchPhase = processFetchPhase(fetchPhase);
/** 要求最後一頁，直接查詢全部資料，有以下特性 1. 最後一筆往前取得每頁筆數為所在資料 2. 請求後 N 頁一律為 0 3. 不會進行第二次查詢 */
PagingRequestBean pagingRequestBean = resultBean.getPagingRequestBean();
if (pagingRequestBean.getPageNumberOfTarget() == PagingRequestBean.LAST_PAGE) {
List<T> resultData = filter.lastPhasePaging(resultBean);
resultBean.setResultSize(resultData.size(), FetchPhase.LastFetch);
return FetchPhase.LastFetch.filterToPage(resultData, pagingRequestBean.getPageSize());
}
// :~)
/** 兩階段查詢 */
// ==================================================
/** 第一次查詢 */
List<T> resultData = filter.firstPhasePaging(resultBean);
resultBean.setResultSize(resultData.size());
// :~)
/** 判斷是否要執行第二次查詢，需滿足以下條件 1. 第一階段沒有任何資料 2. 設定為二階段查詢 3. 請求的分頁大於 1 */
if (resultBean.getResultStatus() == ResultStatus.EmptyData
&& fetchPhase == FetchPhase.LastFetch
&& pagingRequestBean.hasPreviousPage()) {
/** 第二階段查詢以「最後一頁」為查詢策略 */
pagingRequestBean.setPageNumberOfTarget(PagingRequestBean.LAST_PAGE);
resultBean.setPagingRequestBean(pagingRequestBean);
// :~)
return runTwoPhasePagingFilter(filter, resultBean); // 遞迴呼叫請求「最後一頁」
}
// :~)
return FetchPhase.FirstFetch.filterToPage(
resultData, resultBean.getPagingRequestBean().getPageSize());
// ================================================== :~)
}
private static void checkValidPagingResultBean(PagingResultBean pagingResultBean) {
notNull(pagingResultBean, "Paging result bean is null");
notNull(pagingResultBean.getPagingRequestBean(), "Request paging data is null");
}
