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项目中，采用的是最新版的框架。截至目前，Spring 版本为4.0.6 ，Hibernate 版本为4.3.5.1，在Hibernate 自带的包中，提供了JPA的最新版本，在集成的过程中，一直不顺利。
1.首先下载Spring和Hibernate的最新的库文件。这里提供集成好的下载链接。
2.导入项目中（导入Spring和Hibernate自带的相应的库文件，在实际执行过程中，会少一些依赖库，如aspectjrt.jar,aopalliance.jar等）
3.在 找到DBCP2和commons-pool2 的库文件，并导入项目中。
4.配置applicationContext.xml
Spring公共配置 org.hibernate.cfg.ImprovedNamingStrategy true update
这种配置方式，可不用再集成JPA的persistence.xml文件。
5. 开始环境测试，新建单元测试类
package com.astar.entity;import java.io.Serializable;import java.util.Date;import javax.persistence.Basic;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.EnumType;import javax.persistence.Enumerated;import javax.persistence.FetchType;import javax.persistence.Id;import javax.persistence.Lob;import javax.persistence.Table;import javax.persistence.Temporal;import javax.persistence.TemporalType;/** * 用于单元测试的Bean * * @author admin * */@SuppressWarnings("serial")@Entity@Table(name="t_unit_test_bean")public class UnitTestBean implements Serializable { @Id //@GeneratedValue(generator = "system-uuid") //@GenericGenerator(name = "system-uuid", strategy = "uuid") private String id; @Column(length = 50) private String name; @Enumerated(EnumType.ORDINAL) private String state; @Lob @Basic(fetch = FetchType.LAZY) private String remark; @Temporal(TemporalType.TIMESTAMP) private Date time; public UnitTestBean() { } public String getId() { return id; } public void setId(String id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getRemark() { return remark; } public void setRemark(String remark) { this.remark = remark; } public Date getTime() { return time; } public void setTime(Date time) { this.time = time; } public String getState() { return state; } public void setState(String state) { this.state = state; }} 6.在项目中的公共common包下，新建dao层。并编写IOperation泛型接口
package com.astar.common.dao;import java.io.Serializable;import java.util.LinkedHashMap;import com.astar.common.base.QueryResult;/** * 数据访问层，全局接口 * 公共底层DAO操作接口，通过泛型实现泛类调用 * @author xiele * @version 1.0 * @date 2014-07-19 10:11 * */public interface IOperations { /** * 保存（持久化）实体 * @param entity */ void save(final T entity); /** * 更新（合并）实体 * @param entity */ void update(final T entity); /** * 删除实体 * @param entity */ void delete(final T entity); /** * 通过id删除实体 * @param id */ void delete(final Object entityId); /** * 懒加载对象 * @param clazz * @param entityId * @return */ T load(Class clazz, final Object entityId); T load(final Object entityId); /** * 查询实体 * @param clazz * @param entityId * @return */ T get(Class clazz, final Object entityId); T get(final Object entityId); /** * * @param entityclass * 泛型 * @param pageNo * 每页开始的索引 * @param pageSize * 最大记录 * @param whereJpql * 查询条件 * @param param * 设置参数 * @param orderby * 排序条件 * @return */ QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params, LinkedHashMap orderby); /** * 重载方法 */ QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, LinkedHashMap orderby); /** * 重载方法 */ QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params); /** * 重载方法 */ QueryResult getScrollData(Class entityclass, int pageNo, int pageSize); /** * 重载方法 * 查询全部实体 */ QueryResult getScrollData(Class entityclass);}
再新建AbstractDaoSupport抽象类，实现该接口，目的是为了重用。
package com.astar.common.dao;import java.io.Serializable;import java.util.LinkedHashMap;import javax.persistence.EntityManager;import javax.persistence.PersistenceContext;import javax.persistence.Query;import org.springframework.transaction.annotation.Propagation;import org.springframework.transaction.annotation.Transactional;import com.astar.common.base.QueryResult;import com.astar.common.util.SqlUtil;import com.google.common.base.Preconditions;/** * 抽象DAO实现，便于被继承，用于处理通用的数据操作 * 默认：方法被加入事物，传播行为：Propagation.REQUIRED * @author xiele * @version 1.0 * @param */@Transactionalpublic abstract class AbstractDaoSupport implements IOperations { /* Class类型，在执行过程中，动态设置类型 */ private Class clazz; /* 注入实体管理器*/ @PersistenceContext private EntityManager em; /** * 获取实体管理器，便于子类访问 * 不可被子类重写 * @return */ protected final EntityManager getEM() { return this.em; } /** * 设置类型，不可被子类重写 * @param clazzToSet */ protected final void setClazz(Class clazzToSet) { this.clazz = Preconditions.checkNotNull(clazzToSet); } @Override public void save(T entity) { Preconditions.checkNotNull(entity); getEM().persist(entity); } @Override public void update(T entity) { getEM().merge(entity); } @Override public void delete(T entity) { getEM().remove(entity); } @Override public void delete(Object entityId) { getEM().remove(getEM().getReference(clazz, entityId)); } @Override @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED) public T load(Class clazz, Object entityId) { try { return getEM().getReference(clazz, entityId); } catch (Exception e) { return null; } } @Override @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED) public T load(Object entityId) { try { return getEM().getReference(this.clazz, entityId); } catch (Exception e) { return null; } } @Override @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED) public T get(Class clazz, Object entityId) { return getEM().find(clazz, entityId); } @Override @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED) public T get(Object entityId) { return getEM().find(this.clazz, entityId); } @SuppressWarnings("unchecked") @Override @Transactional(readOnly = true, propagation = Propagation.NOT_SUPPORTED) public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params, LinkedHashMap orderby) { QueryResult qr = new QueryResult (); String entityName = SqlUtil.getEntityName(entityclass); String sql = "select o from " + entityName + " o " + (whereJpql == null ? "" : "where " + whereJpql) + SqlUtil.buildOrderby(orderby); String sql2 = "select count(o) from " + entityName + " o " + (whereJpql == null ? "" : "where " + whereJpql); Query query = em.createQuery(sql2); SqlUtil.setParamters(query, params); qr.setCount((Long) query.getSingleResult()); if (qr.getCount() % pageSize == 0) { qr.setPageCount(qr.getCount() / pageSize); } else { qr.setPageCount(qr.getCount() / pageSize + 1); } query = em.createQuery(sql); SqlUtil.setParamters(query, params); if (pageNo != -1 && pageSize != -1) { if (pageNo > qr.getPageCount()) { pageNo = qr.getPageCount().intValue(); } if (pageNo < 1) { pageNo = 1; } qr.setPageNo(pageNo); query.setFirstResult((pageNo - 1) * pageSize); query.setMaxResults(pageSize); } qr.setResults(query.getResultList()); return qr; } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, LinkedHashMap orderby) { return getScrollData(entityclass, pageNo, pageSize, null, null, orderby); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params) { return getScrollData(entityclass, pageNo, pageSize, whereJpql, params, null); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize) { return getScrollData(entityclass, pageNo, pageSize, null); } @Override public QueryResult getScrollData(Class entityclass) { return getScrollData(entityclass, -1, -1, null, null, null); } }
7.在项目中的公用的common包中，新建service层，用于放置公用的抽象业务实现类。
package com.astar.common.service;import java.io.Serializable;import java.util.LinkedHashMap;import javax.transaction.Transactional;import com.astar.common.base.QueryResult;import com.astar.common.dao.IOperations;/** * 抽象业务实现类 * * @author xiele * @version 1.0 */@Transactionalpublic abstract class AbstractService implements IOperations { /** * 抽象方法，用于被具体实现类访问，提供底层调用 * * @return */ protected abstract IOperations getDao(); @Override public void save(T entity) { getDao().save(entity); } @Override public void update(T entity) { getDao().update(entity); } @Override public void delete(T entity) { getDao().delete(entity); } @Override public void delete(Object entityId) { getDao().delete(entityId); } @Override public T load(Class clazz, Object entityId) { return getDao().load(clazz, entityId); } @Override public T load(Object entityId) { return getDao().load(entityId); } @Override public T get(Class clazz, Object entityId) { return getDao().get(clazz, entityId); } @Override public T get(Object entityId) { return getDao().get(entityId); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params, LinkedHashMap orderby) { return getDao().getScrollData(entityclass, pageNo, pageSize, whereJpql, params, orderby); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, LinkedHashMap orderby) { return getDao().getScrollData(entityclass, pageNo, pageSize, orderby); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize, String whereJpql, Object[] params) { return getDao().getScrollData(entityclass, pageNo, pageSize, whereJpql, params); } @Override public QueryResult getScrollData(Class entityclass, int pageNo, int pageSize) { return getDao().getScrollData(entityclass, pageNo, pageSize); } @Override public QueryResult getScrollData(Class entityclass) { return getDao().getScrollData(entityclass); } }
8.新建IUnitTestDao接口
package com.astar.unit;import com.astar.common.dao.IOperations;import com.astar.entity.UnitTestBean;public interface IUnitTestDao extends IOperations { //让所有的DAO都实现基本的操作接口IOperations //除了实现IOperations中的基本操作之外，特定的DAO要实现其他操作可以在对应的接口DAO中定义方法， //此处UserDao的接口IUserDao不需要实现其他方法}
9. 新建UnitTestDaoImpl实现类
package com.astar.unit;import org.springframework.stereotype.Repository;import com.astar.common.dao.AbstractDaoSupport;import com.astar.entity.UnitTestBean;@Repository("unitTestDao")public class UnitTestDaoImpl extends AbstractDaoSupport implements IUnitTestDao { public UnitTestDaoImpl() { setClazz(UnitTestBean.class); } } 10. 新建IUnitTestServcie接口
package com.astar.unit;import com.astar.common.dao.IOperations;import com.astar.entity.UnitTestBean;public interface IUnitTestService extends IOperations {}
11 新建UnitTestServiceImpl实现类
package com.astar.unit;import javax.annotation.Resource;import org.springframework.stereotype.Service;import com.astar.common.dao.IOperations;import com.astar.common.service.AbstractService;import com.astar.entity.UnitTestBean;@Service("unitTestService")public class UnitTestServiceImpl extends AbstractService implements IUnitTestService{ @Resource(name="unitTestDao") private IUnitTestDao dao; public UnitTestServiceImpl() { } @Override protected IOperations getDao() { return this.dao; }} 12 新建单元测试类
package com.astar.unit;import java.util.Date;import java.util.UUID;import javax.persistence.EntityManagerFactory;import org.junit.Test;import org.springframework.context.support.ClassPathXmlApplicationContext;import com.astar.entity.UnitTestBean;public class SpringEnvTest { @Test public void test() { ClassPathXmlApplicationContext cxt = new ClassPathXmlApplicationContext("config/applicationContext-dbcp.xml"); //EntityManagerFactory em = (EntityManagerFactory)cxt.getBean("entityManagerFacotry"); //System.out.println("EM: " + em); IUnitTestDao id = (IUnitTestDao)cxt.getBean("unitTestDao"); System.out.println("ID: " + id); IUnitTestService is = (IUnitTestService) cxt.getBean("unitTestService"); System.out.println("IS: " + is); UnitTestBean utb = new UnitTestBean(); String uuid = UUID.randomUUID().toString(); System.out.println("UUID: " + uuid); utb.setId(uuid); utb.setName("unit"); utb.setTime(new Date()); utb.setRemark("关键字，去死吧"); is.save(utb); }} 13.结论
正常情况下，测试OK。要注意的是，实体的属性不要和数据库关键字冲突，比如desc,user,distinct等。这是我搭建的项目框架，便于小组的人分工开发，包层次结构参考上一篇文章，思想是Package By Feature。欢迎讨论。
14. 缺陷是，在中小系统中，每次都通过Service调用dao.还要再通过接口的形式，会比较繁琐。希望能找到更好的解决方案。
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