import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;
import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Projections;
import org.springframework.orm.hibernate5.support.HibernateDaoSupport;
public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T> {
private Class clazz;//用於接收運行期泛型類型
public BaseDaoImpl() {
//獲得當前類型的帶有泛型類型的父類
ParameterizedType ptClass = (ParameterizedType) this.getClass().getGenericSuperclass();
//獲得運行期的泛型類型
clazz = (Class) ptClass.getActualTypeArguments()[0];
}
@Override
public void save(T t) {
getHibernateTemplate().save(t);
}
@Override
public void delete(T t) {
getHibernateTemplate().delete(t);
}
@Override
public void delete(Serializable id) {
T t = this.getById(id);//先取,再刪
getHibernateTemplate().delete(t);
}
@Override
public void update(T t) {
getHibernateTemplate().update(t);
}
@Override
public T getById(Serializable id) {
return (T) getHibernateTemplate().get(clazz, id);
}
@Override
public Integer getTotalCount(DetachedCriteria dc) {
//設置查詢的聚合函數,總記錄數
dc.setProjection(Projections.rowCount());
List<Long> list = (List<Long>) getHibernateTemplate().findByCriteria(dc);
//清空之前設置的聚合函數
dc.setProjection(null);
if(list!=null && list.size()>0){
Long count = list.get(0);
return count.intValue();
}else{
return null;
}
}
@Override
public List<T> getPageList(DetachedCriteria dc, Integer start, Integer pageSize) {
List<T> list = (List<T>) getHibernateTemplate().findByCriteria(dc, start, pageSize);
return list;
}
}
BaseDaoImpl<T> 繼承了(extends) HibernateDaoSupport 類和實現(implements) BaseDao<T>接口