HibernateDao.java

jopen 9年前發布 | 3K 次閱讀 Java Hibernate
/**

Copyright (c) 2005-2010 springside.org.cn
*

Licensed under the Apache License, Version 2.0 (the "License");


$Id: HibernateDao.java 1205 2010-09-09 15:12:17Z calvinxiu $
*/


package com.dao.hibernate;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.math.NumberUtils;
import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.SessionFactory;
import org.hibernate.criterion.CriteriaSpecification;
import org.hibernate.criterion.Criterion;
import org.hibernate.criterion.Disjunction;
import org.hibernate.criterion.MatchMode;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projection;
import org.hibernate.criterion.Projections;
import org.hibernate.criterion.Restrictions;
import org.hibernate.impl.CriteriaImpl;
import org.hibernate.transform.ResultTransformer;
import org.springframework.util.Assert;
import com.dao.hibernate.PropertyFilter.MatchType;
import com.utils.ReflectionUtils;
/**

封裝SpringSide擴展功能的Hibernat DAO泛型基類.


擴展功能包括分頁查詢,按屬性過濾條件列表查詢. 可在Service層直接使用,也可以擴展泛型DAO子類使用,見兩個構造函數的注釋.


@param <T>

DAO操作的對象類型

@param <PK>

主鍵類型


@author calvin
*/


public class HibernateDao<T, PK extends Serializable> extends
SimpleHibernateDao<T, PK> {
/**

用于Dao層子類的構造函數. 通過子類的泛型定義取得對象類型Class. eg. public class UserDao extends

HibernateDao<User, Long>{ }
*/
public HibernateDao() {
super();
}


/**

用于省略Dao層, Service層直接使用通用HibernateDao的構造函數. 在構造函數中定義對象類型Class. eg.

HibernateDao<User, Long> userDao = new HibernateDao<User,

Long>(sessionFactory, User.class);
*/
public HibernateDao(final SessionFactory sessionFactory,
final Class<T> entityClass) {
super(sessionFactory, entityClass);
}


// -- 分頁查詢函數 --//
/**

分頁獲取全部對象.
*/
public Page<T> getAll(final Page<T> page) {
return findPage(page);
}


/**

按HQL分頁查詢.


@param page

分頁參數. 注意不支持其中的orderBy參數.

@param hql

hql語句.

@param values

數量可變的查詢參數,按順序綁定.


@return 分頁查詢結果, 附帶結果列表及所有查詢輸入參數.
*/
public Page<T> findPage(final Page<T> page, final String hql,
final Object... values) {
Assert.notNull(page, "page不能為空");


Query q = createQuery(hql, values);
if (page.isAutoCount()) {
long totalCount = countHqlResult(hql, values);
page.setTotalCount(totalCount);
}
setPageParameterToQuery(q, page);
List result = q.list();
page.setResult(result);
return page;
}
/**

按HQL分頁查詢.


@param page

分頁參數. 注意不支持其中的orderBy參數.

@param hql

hql語句.

@param values

命名參數,按名稱綁定.


@return 分頁查詢結果, 附帶結果列表及所有查詢輸入參數.
*/
@SuppressWarnings("unchecked")
public Page<T> findPage(final Page<T> page, final String hql,
final Map<String, ?> values) {
Assert.notNull(page, "page不能為空");


Query q = createQuery(hql, values);
if (page.isAutoCount()) {
long totalCount = countHqlResult(hql, values);
page.setTotalCount(totalCount);
}
setPageParameterToQuery(q, page);
List result = q.list();
page.setResult(result);
return page;
}
/**

按Criteria分頁查詢.


@param page

分頁參數.

@param criterions

數量可變的Criterion.


@return 分頁查詢結果.附帶結果列表及所有查詢輸入參數.
*/
@SuppressWarnings("unchecked")
public Page<T> findPage(final Page<T> page, final Criterion... criterions) {
Assert.notNull(page, "page不能為空");


Criteria c = createCriteria(criterions);
if (page.isAutoCount()) {
long totalCount = countCriteriaResult(c);
page.setTotalCount(totalCount);
}
if(page.getPageNo() > page.getTotalPages()) {
page.setPageNo(NumberUtils.toInt(Long.toString(page.getTotalPages())));
}
setPageParameterToCriteria(c, page);
List result = c.list();
page.setResult(result);
return page;
}
/**

設置分頁參數到Query對象,輔助函數.
*/
protected Query setPageParameterToQuery(final Query q, final Page<T> page) {


Assert.isTrue(page.getPageSize() > 0, "Page Size must larger than zero");
// hibernate的firstResult的序號從0開始
q.setFirstResult(page.getFirst() - 1);
q.setMaxResults(page.getPageSize());
return q;
}
/**

設置分頁參數到Criteria對象,輔助函數.
*/
protected Criteria setPageParameterToCriteria(final Criteria c,
final Page<T> page) {


Assert.isTrue(page.getPageSize() > 0, "Page Size must larger than zero");
// hibernate的firstResult的序號從0開始
c.setFirstResult(page.getFirst() - 1);
c.setMaxResults(page.getPageSize());
if (page.isOrderBySetted()) {
String[] orderByArray = StringUtils.split(page.getOrderBy(), ',');
String[] orderArray = StringUtils.split(page.getOrder(), ',');
Assert.isTrue(orderByArray.length == orderArray.length,
"分頁多重排序參數中,排序字段與排序方向的個數不相等");
for (int i = 0; i < orderByArray.length; i++) {
if (Page.ASC.equals(orderArray[i])) {
c.addOrder(Order.asc(orderByArray[i]));
} else {
c.addOrder(Order.desc(orderByArray[i]));
}
}
}
return c;
}
/**

執行count查詢獲得本次Hql查詢所能獲得的對象總數.


本函數只能自動處理簡單的hql語句,復雜的hql查詢請另行編寫count語句查詢.
*/
protected long countHqlResult(final String hql, final Object... values) {
String countHql = prepareCountHql(hql);


try {
Long count = findUnique(countHql, values);
return count;
} catch (Exception e) {
throw new RuntimeException("hql can't be auto count, hql is:"

countHql, e);
}
}


/**

執行count查詢獲得本次Hql查詢所能獲得的對象總數.


本函數只能自動處理簡單的hql語句,復雜的hql查詢請另行編寫count語句查詢.
*/
protected long countHqlResult(final String hql, final Map<String, ?> values) {
String countHql = prepareCountHql(hql);


try {
Long count = findUnique(countHql, values);
return count;
} catch (Exception e) {
throw new RuntimeException("hql can't be auto count, hql is:"

countHql, e);
}
}


private String prepareCountHql(String orgHql) {
String fromHql = orgHql;
// select子句與order by子句會影響count查詢,進行簡單的排除.
fromHql = "from " + StringUtils.substringAfter(fromHql, "from");
fromHql = StringUtils.substringBefore(fromHql, "order by");
String countHql = "select count(*) " + fromHql;
return countHql;
}
/**

執行count查詢獲得本次Criteria查詢所能獲得的對象總數.
*/
@SuppressWarnings("unchecked")
protected long countCriteriaResult(final Criteria c) {
CriteriaImpl impl = (CriteriaImpl) c;


// 先把Projection、ResultTransformer、OrderBy取出來,清空三者后再執行Count操作
Projection projection = impl.getProjection();
ResultTransformer transformer = impl.getResultTransformer();
List<CriteriaImpl.OrderEntry> orderEntries = null;
try {
orderEntries = (List) ReflectionUtils.getFieldValue(impl,
"orderEntries");
ReflectionUtils
.setFieldValue(impl, "orderEntries", new ArrayList());
} catch (Exception e) {
logger.error("不可能拋出的異常:{}", e.getMessage());
}
// 執行Count查詢
Long totalCountObject = Long.parseLong(c
.setProjection(Projections.rowCount()).uniqueResult()
.toString());
long totalCount = (totalCountObject != null) ? totalCountObject : 0;
// 將之前的Projection,ResultTransformer和OrderBy條件重新設回去
c.setProjection(projection);
if (projection == null) {
c.setResultTransformer(CriteriaSpecification.ROOT_ENTITY);
}
if (transformer != null) {
c.setResultTransformer(transformer);
}
try {
ReflectionUtils.setFieldValue(impl, "orderEntries", orderEntries);
} catch (Exception e) {
logger.error("不可能拋出的異常:{}", e.getMessage());
}
return totalCount;
}
// -- 屬性過濾條件(PropertyFilter)查詢函數 --//
/**

按屬性查找對象列表,支持多種匹配方式.


@param matchType

匹配方式,目前支持的取值見PropertyFilter的MatcheType enum.
*/
public List<T> findBy(final String propertyName, final Object value,
final MatchType matchType) {
Criterion criterion = buildCriterion(propertyName, value, matchType);
return find(criterion);
}


/**

按屬性過濾條件列表查找對象列表.
*/
public List<T> find(List<PropertyFilter> filters) {
Criterion[] criterions = buildCriterionByPropertyFilter(filters);
return find(criterions);
}


/**

按屬性過濾條件列表分頁查找對象.
*/
public Page<T> findPage(final Page<T> page,
final List<PropertyFilter> filters) {
Criterion[] criterions = buildCriterionByPropertyFilter(filters);
return findPage(page, criterions);
}


/**

按屬性條件參數創建Criterion,輔助函數.
*/
protected Criterion buildCriterion(final String propertyName,
final Object propertyValue, final MatchType matchType) {
Assert.hasText(propertyName, "propertyName不能為空");
Criterion criterion = null;
// 根據MatchType構造criterion
switch (matchType) {
case EQ:
criterion = Restrictions.eq(propertyName, propertyValue);
break;
case LIKE:
criterion = Restrictions.like(propertyName, (String) propertyValue,
MatchMode.ANYWHERE);
break;


case LE:
criterion = Restrictions.le(propertyName, propertyValue);
break;
case LT:
criterion = Restrictions.lt(propertyName, propertyValue);
break;
case GE:
criterion = Restrictions.ge(propertyName, propertyValue);
break;
case GT:
criterion = Restrictions.gt(propertyName, propertyValue);
}
return criterion;
}
/**

按屬性條件列表創建Criterion數組,輔助函數.
*/
protected Criterion[] buildCriterionByPropertyFilter(
final List<PropertyFilter> filters) {
List<Criterion> criterionList = new ArrayList<Criterion>();
for (PropertyFilter filter : filters) {
if (!filter.hasMultiProperties()) { // 只有一個屬性需要比較的情況.
Criterion criterion = buildCriterion(filter.getPropertyName(),
filter.getMatchValue(), filter.getMatchType());
criterionList.add(criterion);
} else {// 包含多個屬性需要比較的情況,進行or處理.
Disjunction disjunction = Restrictions.disjunction();
for (String param : filter.getPropertyNames()) {
Criterion criterion = buildCriterion(param,
filter.getMatchValue(), filter.getMatchType());
disjunction.add(criterion);
}
criterionList.add(disjunction);
}
}
return criterionList.toArray(new Criterion[criterionList.size()]);
}


}
</pre>
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Java Hibernate
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