Spring 虽然为 Hibernate提供了HibernateDaoSupport 和HibernateTemplate等增强的工具类，在实际的使用中，有时候我们需要将查询出来的信息封装到一个bean中，有时候需要只更新几个列的值，有时候需要做自增，有时候仅仅需要查询一个字段的内容等等；所以很多时候还是需要自己封装一个而已复用的抽象层作为Dao的父类，提供一些通用的方法来实现一些经常用的功能；
这里就分享一个自己觉得很好用的Hibernate Dao抽象实现类，来源是出于对SHOP++项目的源代码学习和改进，加上一些平时对用的频率比较高的方法。
————————【点击查看最新代码·下面的代码不是最新版】————————
package com.fengyunhe.common.hibernate;
import com.fengyunhe.common.bean.Page;
import com.fengyunhe.common.bean.PageList;
import org.apache.commons.lang3.StringUtils;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.engine.query.HQLQueryPlan;
import org.hibernate.engine.query.QueryPlanCache;
import org.springframework.stereotype.Repository;
import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
/**
* Hibernate dao 基础类，一个Hibernate的dao类继承此抽象类后，需要实现 setSessionFactory 方法，注入数据源
*
* @param <T> 对象类型
* @param <PK> 对象主键类型
*/
@Repository
public abstract class HibernateBaseDaoImpl<T, PK extends Serializable> implements
HibernateDao<T, PK> {
protected SessionFactory sessionFactory;
/**
* 注入对应的数据源
*
* @param sessionFactory
*/
protected abstract void setSessionFactory(SessionFactory sessionFactory);
private Class<T> entityClass;
protected HibernateBaseDaoImpl() {
Class c = getClass();
Type type = c.getGenericSuperclass();
if (type instanceof ParameterizedType) {
Type[] parameterizedType = ((ParameterizedType) type)
.getActualTypeArguments();
this.entityClass = (Class<T>) parameterizedType[0];
}
}
@Override
public Session getCurrentSession() {
return sessionFactory.getCurrentSession();
}
@Override
public Session openSession() {
return sessionFactory.openSession();
}
@Override
public void beginTransaction() {
getCurrentSession().beginTransaction();
}
@Override
public void commitTransaction() {
getCurrentSession().getTransaction().commit();
}
@Override
public void rollbackTransaction() {
getCurrentSession().getTransaction().rollback();
}
@Override
public void closeSession(Session session) {
session.close();
}
@Override
public T getById(PK id) {
return (T) getCurrentSession().get(entityClass, id);
}
@Override
public T loadById(PK id) {
return (T) getCurrentSession().load(entityClass, id);
}
@Override
public <T1> T1 getPropertyById(PK id, String propertyName, Class<T1> clazz) {
return getUniqueResult(clazz, "select " + propertyName + " from " + entityClass.getName() + " where " + sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName() + "=?", id);
}
@Override
public void save(T model) {
getCurrentSession().save(model);
}
@Override
public void saveOrUpdate(T model) {
getCurrentSession().saveOrUpdate(model);
}
@Override
public List<T> findListByProperty(String propertyName, Object value) {
Query query = getCurrentSession().createQuery("from " + entityClass.getName() + " where " + propertyName + "=?");
query.setParameter(0, value);
return query.list();
}
@Override
public void delete(T model) {
getCurrentSession().delete(model);
}
@Override
public void deleteById(PK... id) {
for (int i = 0; i < id.length; i++) {
execute("delete from " + entityClass.getName() + " where " + sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName() + "=?", id[i]);
}
}
@Override
public void update(T model) {
getCurrentSession().update(model);
}
@Override
public List<T> findAll() {
return getCurrentSession().createCriteria(entityClass.getName()).list();
}
@Override
public void deleteResultsByProperty(String propertyName, Object value) {
Query query = getCurrentSession().createQuery("delete from " + entityClass.getName() + " where " + propertyName + "=?");
query.setParameter(0, value);
query.executeUpdate();
}
@Override
public PageList<T> findByPage(Page page, String hql, List<Object> params) {
Query q = getCurrentSession().createQuery(hql);
if (page instanceof Page.Offset) {
q.setFirstResult(((Page.Offset) page).getStart()).setMaxResults(
((Page.Offset) page).getLimit());
} else {
q.setFirstResult((page.getPage() - 1) * page.getPageSize())
.setMaxResults(page.getPageSize());
}
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
page.setTotal(this.getTotalCount(hql, params));
return new PageList<T>(page, q.list());
}
@Override
public PageList<T> findByPage(Page page) {
return this.findByPage(page, "from " + this.entityClass.getName(),
Collections.EMPTY_LIST);
}
@Override
public PageList<T> findByPage(Page page, String hql, Object... params) {
return this.findByPage(page, hql, Arrays.asList(params));
}
@Override
public void clear() {
getCurrentSession().clear();
}
@Override
public void flush() {
getCurrentSession().flush();
}
@Override
public void evict(Object o) {
getCurrentSession().evict(o);
}
@Override
public boolean isExist(String propertyName, Object value) {
String hql = "select count(*) from " + entityClass.getName()
+ " where " + propertyName + "=?";
return (Long) getCurrentSession().createQuery(hql)
.setParameter(0, value).uniqueResult() > 0;
}
@Override
public long getTotalCount() {
String hql = "select count(*) from " + entityClass.getName();
return Long.valueOf(getCurrentSession().createQuery(hql).uniqueResult()
.toString());
}
@Override
public long getTotalCount(String hql, List<Object> params) {
Query q = getCurrentSession().createQuery(prepareCountHql(hql));
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
Object singleResult = q.uniqueResult();
if (singleResult instanceof Object[]) {
return Long.valueOf(((Object[]) singleResult)[0].toString()).longValue();
}
return Long.valueOf(singleResult.toString()).longValue();
}
@Override
public long getTotalCount(String hql, Object... params) {
return this.getTotalCount(hql,
params == null ? null : Arrays.asList(params));
}
protected String prepareCountHql(String hql) {
String fromHql = hql;
fromHql = " from " + StringUtils.substringAfter(fromHql, "from ");
fromHql = StringUtils.substringBefore(fromHql, "order by");
//取出查询的字段
String selectWhat = StringUtils.substringBetween(hql, "select", "from");
// 如果是new ClassName (x.x.x)格式的处理
if (selectWhat != null && selectWhat.contains("new ") && selectWhat.contains("(") && selectWhat.contains(")")) {
selectWhat = StringUtils.substringBetween(selectWhat, "(", ")");
}
// 第一列查询总行数
String countHql = "select count(*)" + (selectWhat == null ? "" : ", " + selectWhat + " ") + fromHql;
return countHql;
}
protected String getCountSql(String originalHql,
SessionFactory sessionFactory) {
SessionFactoryImplementor sessionFactoryImplementor = (SessionFactoryImplementor) sessionFactory;
HQLQueryPlan hqlQueryPlan = sessionFactoryImplementor
.getQueryPlanCache().getHQLQueryPlan(originalHql, false,
Collections.emptyMap());
String[] sqls = hqlQueryPlan.getSqlStrings();
String countSql = "select count(*) from (" + sqls[0] + ") count";
return countSql;
}
public SessionFactoryImplementor getSessionFactoryImplementor() {
return (SessionFactoryImplementor) sessionFactory;
}
public QueryPlanCache getQueryPlanCache() {
return getSessionFactoryImplementor().getQueryPlanCache();
}
public HQLQueryPlan getHqlQueryPlan(String hql) {
return getQueryPlanCache().getHQLQueryPlan(hql, false,
Collections.emptyMap());
}
protected String prepareCountSql(String sql) {
return getCountSql(sql, sessionFactory);
}
@Override
public <T> List<T> findList(Class<T> clazz, String hql, List<Object> params) {
Query q = getCurrentSession().createQuery(hql);
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
return q.list();
}
@Override
public <T> List<T> findListLimit(Class<T> clazz, String hql, int limit,
List<Object> params) {
Query q = getCurrentSession().createQuery(hql);
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
q.setFirstResult(0);
q.setMaxResults(limit);
return q.list();
}
@Override
public T getUniqueResult(String hql, Object... params) {
return getUniqueResult(this.entityClass, hql, params);
}
@Override
public <T> T getUniqueResult(Class<T> clazz, String hql, List<Object> params) {
Query q = getCurrentSession().createQuery(hql);
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
q.setFirstResult(0);
q.setMaxResults(1);
List list = q.list();
if (list == null || list.isEmpty() || list.get(0) == null) {
return null;
}
return (T) list.get(0);
}
@Override
public <T> List<T> findList(Class<T> clazz, String hql, Object... params) {
return this.findList(clazz, hql,
params == null ? null : Arrays.asList(params));
}
@Override
/**
* 用给定的HQL和参数查询前几条给定类型的数据列表
* @param clazz
* @param hql
* @param limit
* @param params
* @return
*/
public <T> List<T> findListLimit(Class<T> clazz, String hql, int limit,
Object... params) {
return this.findListLimit(clazz, hql, limit, params == null ? null
: Arrays.asList(params));
}
@Override
public <T> PageList<T> findPageList(Page page, Class<T> clazz, String hql,
Object... params) {
return findPageList(page, clazz, hql, Arrays.asList(params));
}
@Override
public <T> PageList<T> findPageList(Page page, Class<T> clazz, String hql,
List<Object> params) {
Query q = getCurrentSession().createQuery(hql);
if (page instanceof Page.Offset) {
q.setFirstResult(((Page.Offset) page).getStart()).setMaxResults(
((Page.Offset) page).getLimit());
} else {
q.setFirstResult((page.getPage() - 1) * page.getPageSize())
.setMaxResults(page.getPageSize());
}
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
page.setTotal(this.getTotalCount(hql, params));
return new PageList(page, q.list());
}
@Override
public T getUniqueResultByProperty(String propertyName, Object value) {
return this.getUniqueResult("from " + this.entityClass.getName()
+ " where " + propertyName + "=?", value);
}
@Override
public <T> T getUniqueResult(Class<T> clazz, String hql, Object... params) {
return this.getUniqueResult(clazz, hql,
params == null ? null : Arrays.asList(params));
}
@Override
public void execute(String hql, List<Object> params) {
Query q = this.getCurrentSession().createQuery(hql);
if (params != null) {
for (int i = 0; i < params.size(); i++) {
q.setParameter(i, params.get(i));
}
}
q.executeUpdate();
}
@Override
public void execute(String hql, Object... params) {
this.execute(hql, params == null ? null : Arrays.asList(params));
}
@Override
public void updateProperty(PK id, String propertyName, Object status) {
String hql = "update " + this.entityClass.getName() + " set " + propertyName + " = ? where " + sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName() + "= ?";
this.execute(hql, status, id);
}
@Override
public void incr(PK id, String propertyName) {
String hql = "update " + this.entityClass.getName() + " set " + propertyName + " = " + propertyName + "+1 where " + sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName() + "= ?";
this.execute(hql, id);
}
@Override
public void incr(PK id, String propertyName, Integer n) {
String hql = "update " + this.entityClass.getName() + " set " + propertyName + " = " + propertyName + "+1 where " + sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName() + "= ?";
this.execute(hql, id, n);
}
@Override
public void updateProperties(PK id, String[] propertyNames, Object[] values) {
String hql = "update " + entityClass.getName() + " set ";
for (int i = 0; i < propertyNames.length; i++) {
hql += propertyNames[i] + "= :v" + i;
if (i + 1 < propertyNames.length) {
hql += ",";
}
}
hql += " where " + getIdPropertyName() + " =:id";
Query query = getCurrentSession().createQuery(hql);
for (int i = 0; i < values.length; i++) {
query.setParameter("v" + i, values[i]);
}
query.setParameter("id", id).executeUpdate();
}
public String getIdPropertyName() {
return sessionFactory.getClassMetadata(this.entityClass).getIdentifierPropertyName();
}
@Override
public boolean deleteAll() {
String hql = "delete " + this.entityClass.getName();
this.execute(hql);
return true;
}
}
了解 工作生活心情记忆 的更多信息
Subscribe to get the latest posts sent to your email.