Hibernate基本DAO功能的封装

import cn.org.rapid_framework.page.Page;
import cn.org.rapid_framework.page.PageUtils;
import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Example;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Projections;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

/**
 * Hibernate基本DAO功能的封装.
 *
 * @author
 */
public abstract class BaseHibernateDao<E, PK extends Serializable> extends HibernateDaoSupport implements EntityDao<E, PK> {

    private Class<E> entityClass;
    protected Logger logger = LoggerFactory.getLogger(getClass()); //NOSONAR
    private static final int DEFAULT_MAX_RESULTS = 2000;

    @SuppressWarnings("unchecked") //NOSONAR
    public BaseHibernateDao() {
        Class typeCls = getClass();
        Type genType = typeCls.getGenericSuperclass();
        while (true) {
            if (!(genType instanceof ParameterizedType)) {
                typeCls = typeCls.getSuperclass();
                genType = typeCls.getGenericSuperclass();
            } else {
                break;
            }
        }
        this.entityClass = (Class<E>) ((ParameterizedType) genType).getActualTypeArguments()[0];
    }

    public void initDao() {
        if (getHibernateTemplate().getMaxResults() == 0) {
            setMaxResults(DEFAULT_MAX_RESULTS);
//                logger.debug("Setting default max results of DAO to " + getHibernateTemplate().getMaxResults());
        }
    }

    /**
     * 设置getHibernateTemplate方式使用时默认的最大返回条数.
     *
     * @param maxResults
     */
    public void setMaxResults(int maxResults) {
        getHibernateTemplate().setMaxResults(maxResults);
    }

    /**
     * 获取getHibernateTemplate方式使用时默认的最大返回条数.
     *
     * @return maxResult
     */
    public int getMaxResults() {
        return getHibernateTemplate().getMaxResults();
    }

    //TODO use javacommon.util.extjs.ExtJsPageHelper
    protected Page<E> pageQuery(int pageNumber, int pageSize, DetachedCriteria detachedCriteria) {
        Criteria criteria = detachedCriteria.getExecutableCriteria(getSession());
        int totalCount = (
                (Integer) criteria.setProjection(Projections.rowCount()).uniqueResult()
        ).intValue();
        criteria.setProjection(null);
        criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
        //criteria = detachedCriteria.getExecutableCriteria(getSession());
        List<E> items = criteria.setFirstResult(PageUtils.getFirstResult(pageNumber, pageSize)).setMaxResults(pageSize).list();
        return new Page<E>(pageNumber, pageSize, totalCount, items);
    }

    protected Page<E> pageQuery(int pageNumber, int pageSize, DetachedCriteria detachedCriteria, Order[] orders) {
        Criteria criteria = detachedCriteria.getExecutableCriteria(getSession());
        int totalCount = (
                (Integer) criteria.setProjection(Projections.rowCount()).uniqueResult()
        ).intValue();
        criteria.setProjection(null);
        criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
        //criteria = detachedCriteria.getExecutableCriteria(getSession());

        for (Order order : orders) {
            criteria.addOrder(order);
        }
        List<E> items = criteria.setFirstResult(PageUtils.getFirstResult(pageNumber, pageSize)).setMaxResults(pageSize).list();
        return new Page<E>(pageNumber, pageSize, totalCount, items);
    }

    /**
     * 查询数据表所有数据.
     *
     * @return List
     */
    @SuppressWarnings("unchecked") //NOSONAR
    public List<E> findAll() {
        return getSession().createCriteria(getEntityClass()).list();
    }

//		/**
//		 * 查询数据表所有的数据并排序.
//		 * @param defaultOrders
//		 * @return List
//		 */
//		@SuppressWarnings("unchecked") //NOSONAR
//		@Deprecated
//		public List<E> findAll(LinkedHashMap<String, Boolean> defaultOrders) {
//			Criteria criteria = getSession().createCriteria(getEntityClass());
//			if (defaultOrders != null && !defaultOrders.isEmpty()){
//				for(Entry<String, Boolean> defaultOrder: defaultOrders.entrySet()){
//					criteria.addOrder(defaultOrder.getValue() ? Order.asc(defaultOrder.getKey()) : Order.desc(defaultOrder.getKey()));
//				}
//			}
//			return criteria.list();
//		}

    /**
     * 查询数据表分页数据.
     *
     * @param start
     * @param limit
     * @return List&lt;Object&gt;
     */
    @SuppressWarnings("unchecked") //NOSONAR
    public List<E> findAllUsePageLimit(int start, int limit) {
        Criteria criteria = getSession().createCriteria(getEntityClass());
        criteria.setFirstResult(start);
        criteria.setMaxResults(limit);
        return criteria.list();
    }

//		/**
//		 * 查询数据表分页数据并排序.
//		 * @param defaultOrders
//		 * @param start
//		 * @param limit
//		 * @return List&lt;Object&gt;
//		 */
//		@SuppressWarnings("unchecked") //NOSONAR
//		public List<E> findAllUsePageLimit(LinkedHashMap<String, Boolean> defaultOrders, int start, int limit) {
//			Criteria criteria = getSession().createCriteria(getEntityClass());
//			if (defaultOrders != null && !defaultOrders.isEmpty())
//				for(Entry<String, Boolean> defaultOrder: defaultOrders.entrySet())
//					criteria.addOrder(defaultOrder.getValue() ? Order.asc(defaultOrder.getKey()) : Order.desc(defaultOrder.getKey()));
//			criteria.setFirstResult(start);
//			criteria.setMaxResults(limit);
//			return criteria.list();
//		}

    /**
     * 保存记录.
     *
     * @param obj
     */
    public void save(E obj) {
        getSession().save(obj);
    }

    /**
     * 保存或修改记录.
     *
     * @param obj
     */
    public void saveOrUpdate(E obj) {
        getSession().saveOrUpdate(obj);
    }

    /**
     * 修改记录.
     *
     * @param obj
     */
    public void update(E obj) {
        getSession().update(obj);
    }

    /**
     * 删除记录.
     *
     * @param obj
     */
    public void delete(E obj) {
        getSession().delete(obj);
    }

    /**
     * 刷新记录.
     *
     * @param obj
     */
    public void refresh(BaseEntity obj) {
        getSession().refresh(obj);
    }

    /**
     * 按照实例构建一个条件查询，实例NULL的属性将被排除条件
     *
     * @param obj
     */
    public List<E> findByExample(E obj) {
        return getSession()
                .createCriteria(this.getEntityClass())
                .add(Example.create(obj))
                .list();
    }

    /**
     * 按照实例构建一个条件查询，实例NULL的属性将被排除条件
     *
     * @param obj
     */
    public E getByExample(E obj) {
        List<?> list = getSession()
                .createCriteria(this.getEntityClass())
                .add(Example.create(obj))
                .list();
        return list.size() == 0 ? null : (E) list.get(0);
    }

    /**
     * 使用数据库的update严格的更新，解决update对象生成脏数据的问题.
     *
     * @param fieldsMap
     * @param conditionMap
     * @return 影响的记录条数
     */
    public int strictUpdate(Map<String, Object> fieldsMap, Map<String, Object> conditionMap) {
        if (fieldsMap.isEmpty()) {
            return 0;
        }

        StringBuilder sqlBuilder = new StringBuilder("update " + this.getEntityClass().getSimpleName() + " set ");
        int i = 0;
        for (String fieldName : fieldsMap.keySet()) {
            if (i > 0) {
                sqlBuilder.append(", ");
            }
            sqlBuilder.append(fieldName + " = :" + fieldName);
            i++;
        }
        sqlBuilder.append(" where ");
        i = 0;
        for (String fieldName : conditionMap.keySet()) {
            if (i > 0) {
                sqlBuilder.append(" and ");
            }
            sqlBuilder.append(fieldName + " = :" + fieldName);
            i++;
        }
        HashMap<String, Object> sqlParamMap = new HashMap<String, Object>();
        sqlParamMap.putAll(fieldsMap);
        sqlParamMap.putAll(conditionMap);
        Query query = getSession().createQuery(sqlBuilder.toString());
        for (Entry<String, Object> entry : sqlParamMap.entrySet()) {
            query.setParameter(entry.getKey(), entry.getValue());
        }

        return query.executeUpdate();
    }

    /**
     * 根据hibernate OID取记录.
     *
     * @param id
     * @return Object
     */
    @SuppressWarnings("unchecked") //NOSONAR
    public E getById(PK id) {
        return (E) getSession().get(getEntityClass(), id);
    }

    public void deleteById(PK id) {
        E obj = getById(id);
        if (obj != null) {
            getSession().delete(obj);
        }
    }

    /**
     * 判断对象某些属性的值在数据库中是否唯一.
     *
     * @param uniquePropertyNames 在POJO里不能重复的属性列表,以逗号分割 如"name,loginid,password"
     */
    public boolean isUnique(E entity, String[] uniquePropertyNames) {
        // TODO implement it
        return false;
    }

    public void flush() {
        getHibernateTemplate().flush();
    }

    protected Class<E> getEntityClass() {
        return entityClass;
    }
}