某一天有这么一个简单的需求，一个页面有N种查询方式，这N种参数可能有也可能没有，
其他A种查询方式是“AND”，剩下的是“OR”。
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某一天有这么一个简单的需求，一个页面有N种查询方式，这N种参数可能有也可能没有，
并且
·只要查询其中的某几个字段（表和表有关联）
·要有分页
·要查询分页后的统计数据（简单，分页后查出来计算也行）
·要查询出分页之前所有数据的统计数据 （这……）
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在有某天有这么一个简单的需求，一个页面有N种查询方式，这N种参数可能有也可能没有，
并且
·只要查询其中的某几个字段（表和表有关联）
·要有分页
·要查询分页后的统计数据（简单，分页后查出来计算也行）
·要查询出分页之前所有数据的统计数据 （这……）
·需要查询的几个字段和条件有些在一个不关联的第三方表里面……这个表的那个字段有时候是填这个表的id，有时候是其他表的 或者随机字符串数据。
不能直接做关联。
1的例子：
Page
userPage = userRepository.findAll(new Specification() {
@Override
public Predicate toPredicate(Root root, CriteriaQuery criteriaQuery, CriteriaBuilder cb) {
List predicates = new ArrayList<>();
List predicatesOr = new ArrayList<>();
if (departId != null && departId > 0) {
Path departIdPath = root.get("depart");
Depart depart = departRepository.findByStoreIdAndIdAndIsDeleted(storeId, departId, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (depart == null) {
throw new AppException("查无此部门：" + departId);
}
predicates.add(cb.equal(departIdPath.as(Depart.class), depart));
}
if (postId != null && postId > 0) {
Path postIdPath = root.get("post");
Post post = postRepository.findByStoreIdAndIdAndIsDeleted(storeId, postId, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (post == null) {
throw new AppException("查无此职位：" + postId);
}
predicates.add(cb.equal(postIdPath.as(Post.class), post));
}
if (cardGradeId != null && cardGradeId > 0) {
DebugPrint.i("cardGradeId", cardGradeId + "");
Path cardPath = root.get("card");
CardGrade cardGrade = cardGradeRepository.findByStoreIdAndIdAndIsDeleted(storeId, cardGradeId, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (cardGrade == null) {
throw new AppException("查无此卡级别：" + cardGradeId);
}
List cardList = cardRepository.findByStoreIdAndCardGradeAndIsDeleted(storeId, cardGrade, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (cardList != null && cardList.size() > 0) {
CriteriaBuilder.In in = cb.in(cardPath);
for (int i = 0; i < cardList.size(); i++) {
in.value(cardList.get(i));
}
predicates.add(in);
} else {
predicates.add(cb.equal(root.get("id").as(Integer.class), -1));
}
}
if (cardStatus != null) {
DebugPrint.i("cardStatus", cardStatus + "");
Path cardPath = root.get("card");
List cardList = cardRepository.findByStoreIdAndCardStatusAndIsDeleted(storeId, cardStatus, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (cardList != null && cardList.size() > 0) {
CriteriaBuilder.In in = cb.in(cardPath);
for (int i = 0; i < cardList.size(); i++) {
in.value(cardList.get(i));
}
predicates.add(in);
} else {
predicates.add(cb.equal(root.get("id").as(Integer.class), -1));
}
}
if (provinceId != null) {
DebugPrint.i("provinceId", provinceId + "");
Path provinceIdPath = root.get("provinceId");
predicates.add(cb.equal(provinceIdPath.as(Integer.class), provinceId));
}
if (cityId != null) {
Path provinceIdPath = root.get("cityId");
predicates.add(cb.equal(provinceIdPath.as(Integer.class), cityId));
}
if (balance != null && flag != null && !flag.isEmpty()) {
Path provinceIdPath = root.get("balance");
if (flag.equals("大于")) {
predicates.add(cb.ge(provinceIdPath.as(BigDecimal.class), balance));
} else if (flag.equals("等于")) {
predicates.add(cb.equal(provinceIdPath.as(BigDecimal.class), balance));
} else if (flag.equals("小于")) {
predicates.add(cb.le(provinceIdPath.as(BigDecimal.class), balance));
} else {
throw new AppException("flag错误，应为 大于、等于或小于，而非：" + flag);
}
}
if (keyword != null && !keyword.isEmpty()) {
Path realNamePath = root.get("realName");
Path mobilePath = root.get("mobile");
Path identityPath = root.get("identity");
Path idcardPath = root.get("idcard");
predicatesOr.add(cb.like(realNamePath.as(String.class), "%" + keyword + "%"));
predicatesOr.add(cb.like(mobilePath.as(String.class), "%" + keyword + "%"));
predicatesOr.add(cb.like(identityPath.as(String.class), "%" + keyword + "%"));
predicatesOr.add(cb.like(idcardPath.as(String.class), "%" + keyword + "%"));
Path cardPath = root.get("card");
List cardList = cardRepository.findByStoreIdAndSnAndIsDeleted(storeId, keyword, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (cardList != null && cardList.size() > 0) {
CriteriaBuilder.In in = cb.in(cardPath);
for (int i = 0; i < cardList.size(); i++) {
in.value(cardList.get(i));
}
predicatesOr.add(in);
}
}
if (cardsn != null && !cardsn.isEmpty()) {
DebugPrint.i("sn", cardsn + "");
Path cardPath = root.get("card");
List cardList = cardRepository.findByStoreIdAndSnAndIsDeleted(storeId, cardsn, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (cardList != null && cardList.size() > 0) {
CriteriaBuilder.In in = cb.in(cardPath);
for (int i = 0; i < cardList.size(); i++) {
in.value(cardList.get(i));
}
predicates.add(in);
} else {
predicates.add(cb.equal(root.get("id").as(Integer.class), -1));
}
}
Predicate[] pre = new Predicate[predicates.size()];
criteriaQuery.where(predicates.toArray(pre)).where();
Predicate predicatesWhere = cb.and(predicates.toArray(pre));
if (predicatesOr.size() > 0) {
Predicate[] preOr = new Predicate[predicatesOr.size()];
criteriaQuery.where(predicatesOr.toArray(preOr)).where();
Predicate predicatesWhereOr = cb.or(predicatesOr.toArray(preOr));
return criteriaQuery.where(predicatesWhere, predicatesWhereOr).getRestriction();
}
return cb.and(predicates.toArray(pre));
}
}, pageable);
2的例子
@PersistenceContext
private EntityManager em;
Map resultMap = new HashMap<>();
Integer storeId = params.containsKey("storeId") ? Integer.parseInt(params.get("storeId").toString()) : 0;
//增减原因 资金变动类型：1-充值、2-发放补贴、3-现金取款、4-补贴取款……
Integer type = params.containsKey("type") ? Integer.parseInt(params.get("type").toString()) : 0;
Integer managerId = params.containsKey("managerId") ? Integer.parseInt(params.get("managerId").toString()) : 0;
Integer departId = params.containsKey("departId") ? Integer.parseInt(params.get("departId").toString()) : 0;
Date beginTime = params.containsKey("beginTime") ? DateUtils.String2Date(params.get("beginTime").toString(), "yyyy-MM-dd HH:mm:ss") : null;
Date endTime = params.containsKey("endTime") ? DateUtils.String2Date(params.get("endTime").toString(), "yyyy-MM-dd HH:mm:ss") : null;
String realName = params.containsKey("realName") ? params.get("realName").toString() : null;
String identity = params.containsKey("identity") ? params.get("identity").toString() : null;
//定义查询字段与别名
String alia_id = "id";
String alia_realName = "realName";
String alia_identity = "identity";
String alia_departTitle = "departTitle";
String alia_changeBalance = "changeBalance";
String alia_changeSubsidy = "changeSubsidy";
String alia_changeDonation = "changeDonation";
String alia_balance = "balance";
String alia_subsidy = "subsidy";
String alia_donation = "donation";
String alia_cardSn = "cardSn";
String alia_type = "type";
String alia_referer = "referer";
String alia_managerName = "managerName";
String alia_createTime = "createTime";
String alia_total = "total";
String alia_sumChangeBalance = "sumChangeBalance";
String alia_sumChangeSubsidy = "sumChangeSubsidy";
String alia_sumChangeDonation = "sumChangeDonation";
CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery criteriaQuery = cb.createTupleQuery();//列表查询
CriteriaQuery criteriaQueryCount = cb.createTupleQuery();//统计查询
Root root = criteriaQuery.from(LogCardCapital.class);
Root rootCount = criteriaQueryCount.from(LogCardCapital.class);
criteriaQuery.multiselect(
root.get("id").alias(alia_id),
root.get("user").get("realName").alias(alia_realName),
root.get("user").get("identity").alias(alia_identity),
root.get("user").get("depart").get("title").alias(alia_departTitle),
root.get("user").get("card").get("sn").alias(alia_cardSn),
root.get("referer").alias(alia_referer),
root.get("type").alias(alia_type),
root.get("managerName").alias(alia_managerName),
root.get("createTime").alias(alia_createTime),
root.get("changeBalance").alias(alia_changeBalance),
root.get("changeSubsidy").alias(alia_changeSubsidy),
root.get("changeDonation").alias(alia_changeDonation),
root.get("balance").alias(alia_balance),
root.get("subsidy").alias(alia_subsidy),
root.get("donation").alias(alia_donation)
);
criteriaQueryCount.multiselect(
cb.count(rootCount.get("id")).alias(alia_total),
cb.sum(rootCount.get("changeBalance")).alias(alia_sumChangeBalance),
cb.sum(rootCount.get("changeDonation")).alias(alia_sumChangeSubsidy),
cb.sum(rootCount.get("changeDonation")).alias(alia_sumChangeDonation)
);
List predicates = new ArrayList<>();
if (storeId != null && storeId > 0) {
Path storeIdPath = root.get("storeId");
predicates.add(cb.equal(storeIdPath.as(Integer.class), storeId));
}
//增减原因
if (type != null && type > 0) {
Path typePath = root.get("type");
predicates.add(cb.equal(typePath.as(Integer.class), type));
}
if (managerId != null && managerId > 0) {
Path managerIdPath = root.get("managerId");
predicates.add(cb.equal(managerIdPath.as(Integer.class), managerId));
}
if (beginTime != null) {
Path createTimePath = root.get("createTime");
predicates.add(cb.greaterThanOrEqualTo(createTimePath.as(Date.class), beginTime));
}
if (endTime != null) {
Path createTimePath = root.get("createTime");
predicates.add(cb.lessThanOrEqualTo(createTimePath.as(Date.class), endTime));
}
if (departId != null && departId > 0) {
Path userPath = root.get("user");
Path departPath = userPath.get("depart");
Depart depart = departRepository.findByStoreIdAndIdAndIsDeleted(storeId, departId, BaseDeleteEnums.BASE_DELETE_NO.getCode());
if (depart == null) {
throw new AppException("查无此部门：" + departId);
}
predicates.add(cb.equal(departPath.as(Depart.class), depart));
}
if (realName != null && !realName.isEmpty()) {
Path userPath = root.get("user");
Path realNamePath = userPath.get("realName");
predicates.add(cb.equal(realNamePath.as(String.class), realName));
}
if (identity != null && !identity.isEmpty()) {
Path userPath = root.get("user");
Path identityPath = userPath.get("identity");
predicates.add(cb.equal(identityPath.as(String.class), identity));
}
criteriaQuery.where(predicates.toArray(new Predicate[predicates.size()]));
criteriaQueryCount.where(predicates.toArray(new Predicate[predicates.size()]));
TypedQuery query = em.createQuery(criteriaQuery);
//int totalRows = query.getResultList().size();
query.setFirstResult(pageNum * pageSize);
query.setMaxResults(pageSize);
List list = query.getResultList();
List> dataList = new ArrayList<>();
if (list != null && !list.isEmpty()) {
for (Tuple tu : list
) {
Map itemmap = new HashMap<>();
for (TupleElement element : tu.getElements()) {
if (element.getAlias().toString().equalsIgnoreCase(alia_type)) {
try {
itemmap.put(alia_type + "Title", EnumsUtil.getEnumObject(Integer.parseInt(tu.get(element.getAlias()).toString()),
CardCapitalTypeEnums.class).getMsg());
} catch (Exception e) {
e.printStackTrace();
}
} else if (element.getAlias().toString().equalsIgnoreCase(alia_referer)) {
try {
itemmap.put(alia_referer + "Title", EnumsUtil.getEnumObject(Integer.parseInt(tu.get(element.getAlias()).toString()),
RefererEnums.class).getMsg());
} catch (Exception e) {
e.printStackTrace();
}
}
itemmap.put(element.getAlias(), tu.get(element.getAlias()));
}
dataList.add(itemmap);
}
}
resultMap.put("list", dataList);
resultMap.put("page", pageNum);
resultMap.put("pageSize", pageSize);
resultMap.put("number", dataList.size());
TypedQuery queryCount = em.createQuery(criteriaQueryCount);
List listcount = queryCount.getResultList();
if (listcount != null && !listcount.isEmpty()) {
Tuple tu = listcount.get(0);
for (TupleElement element : tu.getElements()) {
resultMap.put(element.getAlias(), tu.get(element.getAlias()));
}
}
3、详细见：https://www.jianshu.com/p/6156bf21374c