Hibernate_根据条件动态组装sql/hql语句(仿ibatis动态查询语句功能)

via: http://blog.csdn.net/crazycoder2010/article/details/7414152

 

1.功能需求背景
  项目中使用hibernate作为数据持久层框架，主要考虑hibernate在进行一些简单的crud操作时非常便利，不需要和ibatis似的为每个sql操作都写一堆文件，但是同时也带来了一些局限性，如类似ibatis强大的动态查询功能用不了了，但是这个功能在项目中的应用场景又很大，hibernate自身也支持将sql/hql语句写在.hbm.xml映射文件中<sql-query>和<query>元素，但是这个功能只能对那些查询限制条件固定的sql有用，对于需要动态拼接的sql语句，hibernate就显得力不从心了，如何给hibernate插上ibatis动态查询的翅膀，既保留crud的简洁性，又能收获ibatis的特性呢？接下来的文章将会重点介绍
2.设计思路
  先看一下ibatis的动态查询时怎么做的
     <select id="getUserList" resultMap="user">
         select * from user
            <isGreaterThan prepend="and" property="id" compareValue="0">
                   where user_id = #userId#
            </isGreaterThan>
             order by createTime desc
    </select>
  ibatis在程序实现内部回去解析sql语句中的标签，然后去解析计算，我们在ibatis在实现的时候也参考了这个解决思路，但是否是需要把ibatis里的解析sql的语法都抄到我们的dao框架中呢-显然这样太复杂了，而且ibatis自己的sql元素是和那些resultMap等是绑定在一起用的，而在hibernate是没用这些东西的，要改造这些东西是一项非常浩大的工程，因此这个方案被放弃了

  我们在实现的时候采取了一种非常简洁又功能强大的方式-模板技术!对，就是利用freemarker把sql/hql中的动态拼接条件判断语法都交给freemarker语法去处理，这样既能复用freemarker框架，又保持了我们框架设计的简洁性-不需要自己写过多的处理逻辑,以下是我们需要进行动态处理的sql/hql语句的样例

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE dynamic-hibernate-statement PUBLIC "-//Haier/HOP Hibernate Dynamic Statement DTD 1.0//EN"
"http://www.haier.com/dtd/dynamic-hibernate-statement-1.0.dtd">
<dynamic-hibernate-statement>
    <!-- 查询某个资源下的直接子节点 -->
    <hql-query name="resource.getChildren">
    <![CDATA[
        from Resource where parent.id=${parentId} and parent.id != id
    ]]>
    </hql-query>
    <!-- 查询系统中所有的root资源 -->
    <hql-query name="resource.getRoots">
    <![CDATA[
        from Resource where parent.id = id order by orderIndex
    ]]>
    </hql-query>
    <!-- 获取某个用户可访问的某个资源下的所有子资源 -->
    <sql-query name="resource.getDescendants">
    <![CDATA[
        select distinct t.id,
                        t.name,
                        t.description,
                        t.url,
                        t.type,
                        t.status,
                        t.code,
                        t.configuration,
                        t.module_name,
                        t.gmt_create,
                        t.gmt_modified,
                        t.create_by,
                        t.last_modified_by,
                        t.order_index,
                        t.parent_id
          from resource_info t
         inner join role_resource rr
            on t.id = rr.resource_id
         inner join user_role ur
            on rr.role_id = ur.role_id
         where ur.user_id = ${userId}
         <#if type == '1'>
            and t.type=1
            <#else>
            and t.type=0
         </#if>
           and t.type =  ${type}
           and t.status =  ${status}
         start with t.code = '${code}'
        connect by nocycle prior t.id = t.parent_id
    ]]>
    </sql-query>
</dynamic-hibernate-statement>

这个文件看起来非常类似ibatis的语句了，只是没用ibatis的哪些标签-改成了freemarker语法，没错，我们就是复用freemarker来帮我们解决这些烦杂的判断操作的

这样我们的动态sql程序就可以总结成以下流程

a.系统加载阶段

  这个阶段程序负责将指定路径下的动态sql文件加载到内存中，一次性缓存起来，没错，这些东西只需要加载一次，以后直接读取就行了，没必要每次去查找，缓存也非常简单，一个Map<String,String>就搞定，key是sql-query或hql-query元素的name属性，value就是与其对应的sql/hql语句

b.程序调用查询阶段

   调用程序通过sql/hql语句的name属性和传入查询参数来得到最终解析出来的语句

我们期望的方法可能是这样的：

public <X> List<X> findByNamedQuery(final String queryName, final Map<String, ?> parameters)

通过queryName从缓存中查找出其对应的sql/hql语句(最原始的，里面带有freemarker语法)

然后通过freemarker模板和传递进去的parameters参数对模板进行解析，得到最终的语句(纯sql/hql)

最后将解析后的sql/hql传递给底层api，返回查询结果

3.实现

  上面介绍了大致的思路，这里介绍具体的代码实现

  3.1DTD定义

      我们是把动态的sql/hql语句放在单独的xml配置文件里的，为了规范xml文档，我们给文档定义了dtd文件，这里我们只定义了两个元素<sql-query>和<hql-query>分别表示sql查询语句和hql查询语句，这两个元素目前自有一个name属性用来唯一标示该语句，如下

<!-- HOP Hibernate Dynamic Statement Mapping DTD.

<!DOCTYPE dynamic-hibernate-statement PUBLIC
    "-//Haier/HOP Hibernate Dynamic Statement DTD 1.0//EN"
    "http://www.haier.com/dtd/dynamic-hibernate-statement-1.0.dtd">

这个文件时用来定义动态参数语句，类似itabis

-->

<!--
    The document root.
 -->

<!ELEMENT dynamic-hibernate-statement (
    (hql-query|sql-query)*
)>
                            <!-- default: none -->

<!-- The query element declares a named Hibernate query string -->

<!ELEMENT hql-query (#PCDATA)>
    <!ATTLIST hql-query name CDATA #REQUIRED>

<!-- The sql-query element declares a named SQL query string -->

<!ELEMENT sql-query (#PCDATA)>
    <!ATTLIST sql-query name CDATA #REQUIRED>

然后将其保存为dynamic-hibernate-statement-1.0.dtd，放在classpath下

编写DTD校验器

 

/**
 * hibernate动态sql dtd解析器
 * @author WangXuzheng
 *
 */
public class DynamicStatementDTDEntityResolver implements EntityResolver, Serializable{
    private static final long serialVersionUID = 8123799007554762965L;
    private static final Logger LOGGER = LoggerFactory.getLogger( DynamicStatementDTDEntityResolver.class );
    private static final String HOP_DYNAMIC_STATEMENT = "http://www.haier.com/dtd/";

    public InputSource resolveEntity(String publicId, String systemId) {
        InputSource source = null; // returning null triggers default behavior
        if ( systemId != null ) {
            LOGGER.debug( "trying to resolve system-id [" + systemId + "]" );
            if ( systemId.startsWith( HOP_DYNAMIC_STATEMENT ) ) {
                LOGGER.debug( "recognized hop dyanmic statement namespace; attempting to resolve on classpath under com/haier/openplatform/dao/hibernate/" );
                source = resolveOnClassPath( publicId, systemId, HOP_DYNAMIC_STATEMENT );
            }
        }
        return source;
    }

    private InputSource resolveOnClassPath(String publicId, String systemId, String namespace) {
        InputSource source = null;
        String path = "com/haier/openplatform/dao/hibernate/" + systemId.substring( namespace.length() );
        InputStream dtdStream = resolveInHibernateNamespace( path );
        if ( dtdStream == null ) {
            LOGGER.debug( "unable to locate [" + systemId + "] on classpath" );
            if ( systemId.substring( namespace.length() ).indexOf( "2.0" ) > -1 ) {
                LOGGER.error( "Don't use old DTDs, read the Hibernate 3.x Migration Guide!" );
            }
        }
        else {
            LOGGER.debug( "located [" + systemId + "] in classpath" );
            source = new InputSource( dtdStream );
            source.setPublicId( publicId );
            source.setSystemId( systemId );
        }
        return source;
    }

    protected InputStream resolveInHibernateNamespace(String path) {
        return this.getClass().getClassLoader().getResourceAsStream( path );
    }

    protected InputStream resolveInLocalNamespace(String path) {
        try {
            return ConfigHelper.getUserResourceAsStream( path );
        }
        catch ( Throwable t ) {
            return null;
        }
    }
}

 

3.2编写sql文件

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE dynamic-hibernate-statement PUBLIC "-//Haier/HOP Hibernate Dynamic Statement DTD 1.0//EN"
"http://www.haier.com/dtd/dynamic-hibernate-statement-1.0.dtd">
<dynamic-hibernate-statement>
    <!-- 查询某个资源下的直接子节点 -->
    <hql-query name="resource.getChildren">
    <![CDATA[
        from Resource where parent.id=${parentId} and parent.id != id
    ]]>
    </hql-query>
    <!-- 查询系统中所有的root资源 -->
    <hql-query name="resource.getRoots">
    <![CDATA[
        from Resource where parent.id = id order by orderIndex
    ]]>
    </hql-query>
    <!-- 获取某个用户可访问的某个资源下的所有子资源 -->
    <sql-query name="resource.getDescendants">
    <![CDATA[
        select distinct t.id,
                        t.name,
                        t.description,
                        t.url,
                        t.type,
                        t.status,
                        t.code,
                        t.configuration,
                        t.module_name,
                        t.gmt_create,
                        t.gmt_modified,
                        t.create_by,
                        t.last_modified_by,
                        t.order_index,
                        t.parent_id
          from resource_info t
         inner join role_resource rr
            on t.id = rr.resource_id
         inner join user_role ur
            on rr.role_id = ur.role_id
         where ur.user_id = ${userId}
         <#if type == '1'>
            and t.type=1
            <#else>
            and t.type=0
         </#if>
           and t.type =  ${type}
           and t.status =  ${status}
         start with t.code = '${code}'
        connect by nocycle prior t.id = t.parent_id
    ]]>
    </sql-query>
</dynamic-hibernate-statement>

3.3加载动态sql文件

这里我们将加载sql/hql语句的程序独立到一个单独的类中，以便独立扩展

这里一共3个方法，分表标示获取系统中sql/hql语句的map(key:语句名称,value:具体的)

/**
 * 动态sql/hql语句组装器
 * @author WangXuzheng
 *
 */
public interface DynamicHibernateStatementBuilder {
    /**
     * hql语句map
     * @return
     */
    public Map<String,String> getNamedHQLQueries();
    /**
     * sql语句map
     * @return
     */
    public Map<String,String> getNamedSQLQueries();
    /**
     * 初始化
     * @throws IOException
     */
    public void init() throws IOException;
}

默认的加载器-将指定配置文件中的sql/hql语句加载到内存中

/**
 * @author WangXuzheng
 *
 */
public class DefaultDynamicHibernateStatementBuilder implements DynamicHibernateStatementBuilder, ResourceLoaderAware {
    private static final Logger LOGGER = LoggerFactory.getLogger(DefaultDynamicHibernateStatementBuilder.class);
    private Map<String, String> namedHQLQueries;
    private Map<String, String> namedSQLQueries;
    private String[] fileNames = new String[0];
    private ResourceLoader resourceLoader;
    private EntityResolver entityResolver = new DynamicStatementDTDEntityResolver();
    /**
     * 查询语句名称缓存，不允许重复
     */
    private Set<String> nameCache = new HashSet<String>();

    public void setFileNames(String[] fileNames) {
        this.fileNames = fileNames;
    }

    @Override
    public Map<String, String> getNamedHQLQueries() {
        return namedHQLQueries;
    }

    @Override
    public Map<String, String> getNamedSQLQueries() {
        return namedSQLQueries;
    }

    @Override
    public void init() throws IOException {
        namedHQLQueries = new HashMap<String, String>();
        namedSQLQueries = new HashMap<String, String>();
        boolean flag = this.resourceLoader instanceof ResourcePatternResolver;
        for (String file : fileNames) {
            if (flag) {
                Resource[] resources = ((ResourcePatternResolver) this.resourceLoader).getResources(file);
                buildMap(resources);
            } else {
                Resource resource = resourceLoader.getResource(file);
                buildMap(resource);
            }
        }
        //clear name cache
        nameCache.clear();
    }

    @Override
    public void setResourceLoader(ResourceLoader resourceLoader) {
        this.resourceLoader = resourceLoader;
    }

    private void buildMap(Resource[] resources) throws IOException {
        if (resources == null) {
            return;
        }
        for (Resource resource : resources) {
            buildMap(resource);
        }
    }

    @SuppressWarnings({ "rawtypes" })
    private void buildMap(Resource resource) {
        InputSource inputSource = null;
        try {
            inputSource = new InputSource(resource.getInputStream());
            XmlDocument metadataXml = MappingReader.INSTANCE.readMappingDocument(entityResolver, inputSource,
                    new OriginImpl("file", resource.getFilename()));
            if (isDynamicStatementXml(metadataXml)) {
                final Document doc = metadataXml.getDocumentTree();
                final Element dynamicHibernateStatement = doc.getRootElement();
                Iterator rootChildren = dynamicHibernateStatement.elementIterator();
                while (rootChildren.hasNext()) {
                    final Element element = (Element) rootChildren.next();
                    final String elementName = element.getName();
                    if ("sql-query".equals(elementName)) {
                        putStatementToCacheMap(resource, element, namedSQLQueries);
                    } else if ("hql-query".equals(elementName)) {
                        putStatementToCacheMap(resource, element, namedHQLQueries);
                    }
                }
            }
        } catch (Exception e) {
            LOGGER.error(e.toString());
            throw new SysException(e);
        } finally {
            if (inputSource != null && inputSource.getByteStream() != null) {
                try {
                    inputSource.getByteStream().close();
                } catch (IOException e) {
                    LOGGER.error(e.toString());
                    throw new SysException(e);
                }
            }
        }

    }

    private void putStatementToCacheMap(Resource resource, final Element element, Map<String, String> statementMap)
            throws IOException {
        String sqlQueryName = element.attribute("name").getText();
        Validate.notEmpty(sqlQueryName);
        if (nameCache.contains(sqlQueryName)) {
            throw new SysException("重复的sql-query/hql-query语句定义在文件:" + resource.getURI() + "中，必须保证name的唯一.");
        }
        nameCache.add(sqlQueryName);
        String queryText = element.getText();
        statementMap.put(sqlQueryName, queryText);
    }

    private static boolean isDynamicStatementXml(XmlDocument xmlDocument) {
        return "dynamic-hibernate-statement".equals(xmlDocument.getDocumentTree().getRootElement().getName());
    }
}

配置一下

    <bean id="dynamicStatementBuilder" class="com.haier.openplatform.dao.hibernate.support.DefaultDynamicHibernateStatementBuilder">
        <property name="fileNames">
            <list>
                <value>classpath*:/**/*-dynamic.xml</value><!--这里我们指定要加载某个文件夹下所有以-dynamic.xml结尾的文件 -->
            </list>
        </property>
    </bean>
    <bean id="baseHibernateDAO" class="com.haier.openplatform.dao.hibernate.BaseDAOHibernateImpl" abstract="true">
        <property name="sessionFactory">
            <ref bean="sessionFactory"/>
        </property>
        <property name="dynamicStatementBuilder" ref="dynamicStatementBuilder"/>
    </bean>

dao层代码

/**
 * Hibernate实现的DAO层
 * @param <T> DAO操作的对象类型
 * @param <ID> 主键类型
 * @author WangXuzheng
 *
 */
public class SimpleHibernateDAO<T,ID extends Serializable> implements BaseDAO<T, ID>,InitializingBean{
    private static final Logger LOGER = LoggerFactory.getLogger(SimpleHibernateDAO.class);
    protected SessionFactory sessionFactory;
    protected Class<T> entityClass;
    /**
     * 模板缓存
     */
    protected Map<String, StatementTemplate> templateCache;
    protected DynamicHibernateStatementBuilder dynamicStatementBuilder;
    /**
     * 通过子类的泛型定义取得对象类型Class.
     * eg.
     * public class UserDao extends SimpleHibernateDao<User, Long>
     */
    public SimpleHibernateDAO() {
        this.entityClass = Reflections.getSuperClassGenricType(getClass());
    }

    /**
     * 取得sessionFactory.
     */
    public SessionFactory getSessionFactory() {
        return sessionFactory;
    }

    /**
     * 采用@Autowired按类型注入SessionFactory, 当有多个SesionFactory的时候在子类重载本函数.
     */
    public void setSessionFactory(final SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
    }

    public void setDynamicStatementBuilder(DynamicHibernateStatementBuilder dynamicStatementBuilder) {
        this.dynamicStatementBuilder = dynamicStatementBuilder;
    }

    /**
     * 取得当前Session.
     */
    public Session getSession() {
        return sessionFactory.getCurrentSession();
    }

    /**
     * 保存新增或修改的对象.
     */
    @Override
    public void save(final T entity) {
        Validate.notNull(entity, "entity不能为空");
        getSession().save(entity);
        LOGER.debug("save entity: {}", entity);
    }

    /**
     * 删除对象.
     *
     * @param entity 对象必须是session中的对象或含id属性的transient对象.
     */
    @Override
    public void delete(final T entity) {
        if(entity == null){
            return;
        }
        getSession().delete(entity);
        LOGER.debug("delete entity: {}", entity);
    }

    /**
     * 按id删除对象.
     */
    @Override
    public void delete(final ID id) {
        Validate.notNull(id, "id不能为空");
        delete(get(id));
        LOGER.debug("delete entity {},id is {}", entityClass.getSimpleName(), id);
    }

    /**
     * 按id获取对象.
     */
    @SuppressWarnings("unchecked")
    @Override
    public T get(final ID id) {
        Validate.notNull(id, "id不能为空");
        return (T) getSession().get(entityClass, id);
    }

    /**
     * 按id列表获取对象列表.
     */
    public List<T> get(final Collection<ID> ids) {
        return find(Restrictions.in(getIdName(), ids));
    }

    /**
     *  获取全部对象.
     */
    @Override
    public List<T> getAll() {
        return find();
    }

    /**
     *  获取全部对象, 支持按属性行序.
     */
    @SuppressWarnings("unchecked")
    public List<T> getAll(String orderByProperty, boolean isAsc) {
        Criteria c = createCriteria();
        if (isAsc) {
            c.addOrder(Order.asc(orderByProperty));
        } else {
            c.addOrder(Order.desc(orderByProperty));
        }
        return c.list();
    }

    /**
     * 按属性查找对象列表, 匹配方式为相等.
     */
    public List<T> findBy(final String propertyName, final Object value) {
        Criterion criterion = Restrictions.eq(propertyName, value);
        return find(criterion);
    }

    /**
     * 按属性查找唯一对象, 匹配方式为相等.
     */
    @SuppressWarnings("unchecked")
    @Override
    public T findUniqueBy(final String propertyName, final Object value) {
        Criterion criterion = Restrictions.eq(propertyName, value);
        return ((T) createCriteria(criterion).uniqueResult());
    }

    /**
     * 按HQL查询对象列表.
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findByHQL(final String hql, final Object... values) {
        return createHQLQuery(hql, values).list();
    }

    /**
     * 按HQL查询对象列表，并将对象封装成指定的对象
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findByHQLRowMapper(RowMapper<X> rowMapper,final String hql, final Object... values) {
        Validate.notNull(rowMapper, "rowMapper不能为空！");
        List<Object[]> result = createHQLQuery(hql, values).list();
        return buildListResultFromRowMapper(rowMapper, result);
    }

    protected <X> List<X> buildListResultFromRowMapper(RowMapper<X> rowMapper, List<Object[]> result) {
        List<X> rs = new ArrayList<X>(result.size());
        for(Object[] obj : result){
            rs.add(rowMapper.fromColumn(obj));
        }
        return rs;
    }


    /**
     * 按SQL查询对象列表.
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findBySQLRowMapper(RowMapper<X> rowMapper,final String sql, final Object... values) {
        Validate.notNull(rowMapper, "rowMapper不能为空！");
        List<Object[]> result = createSQLQuery(sql, values).list();
        return buildListResultFromRowMapper(rowMapper, result);
    }

    /**
     * 按SQL查询对象列表,并将结果集转换成指定的对象列表
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findBySQL(final String sql, final Object... values) {
        return createSQLQuery(sql, values).list();
    }

    /**
     * 按HQL查询对象列表.
     *
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findByHQL(final String hql, final Map<String, ?> values) {
        return createHQLQuery(hql, values).list();
    }

    /**
     * 按HQL查询对象列表,并将结果集封装成对象列表
     *
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findByHQLRowMapper(RowMapper<X> rowMapper,final String hql, final Map<String, ?> values) {
        Validate.notNull(rowMapper, "rowMapper不能为空！");
        List<Object[]> result = createHQLQuery(hql, values).list();
        return buildListResultFromRowMapper(rowMapper, result);
    }

    /**
     * 按SQL查询对象列表.
     * @param sql SQL查询语句
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findBySQL(final String sql, final Map<String, ?> values) {
        return createSQLQuery(sql, values).list();
    }

    /**
     * 查询在xxx.hbm.xml中配置的查询语句
     * @param queryName 查询的名称
     * @param parameters 参数
     * @return
     */
    public <X> List<X> findByNamedQuery(final String queryName, final Map<String, ?> parameters) {
        StatementTemplate statementTemplate = templateCache.get(queryName);
        String statement = processTemplate(statementTemplate,parameters);
        if(statementTemplate.getType() == StatementTemplate.TYPE.HQL){
            return this.findByHQL(statement);
        }else{
            return this.findBySQL(statement);
        }
    }

    /**
     * 查询在xxx.hbm.xml中配置的查询语句
     * @param rowMapper
     * @param queryName 查询的名称
     * @param parameters 参数
     * @return
     */
    public <X> List<X> findByNamedQuery(RowMapper<X> rowMapper,final String queryName, final Map<String, ?> parameters) {
        StatementTemplate statementTemplate = templateCache.get(queryName);
        String statement = processTemplate(statementTemplate,parameters);
        if(statementTemplate.getType() == StatementTemplate.TYPE.HQL){
            return this.findByHQLRowMapper(rowMapper,statement);
        }else{
            return this.findBySQLRowMapper(rowMapper,statement);
        }
    }

    /**
     * 按SQL查询对象列表,并将结果集封装成对象列表
     * @param sql SQL查询语句
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> List<X> findBySQLRowMapper(RowMapper<X> rowMapper,final String sql, final Map<String, ?> values) {
        Validate.notNull(rowMapper, "rowMapper不能为空！");
        List<Object[]> result = createSQLQuery(sql, values).list();
        return buildListResultFromRowMapper(rowMapper, result);
    }

    /**
     * 按HQL查询唯一对象.
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> X findUniqueByHQL(final String hql, final Object... values) {
        return (X) createHQLQuery(hql, values).uniqueResult();
    }

    /**
     * 按SQL查询唯一对象.
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> X findUniqueBySQL(final String sql, final Object... values) {
        return (X) createSQLQuery(sql, values).uniqueResult();
    }

    /**
     * 按HQL查询唯一对象.
     *
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> X findUniqueByHQL(final String hql, final Map<String, ?> values) {
        return (X) createHQLQuery(hql, values).uniqueResult();
    }

    /**
     * 按HQL查询唯一对象.
     * @param sql sql语句
     * @param values 命名参数,按名称绑定.
     */
    @SuppressWarnings("unchecked")
    public <X> X findUniqueBySQL(final String sql, final Map<String, ?> values) {
        return (X) createSQLQuery(sql, values).uniqueResult();
    }

    /**
     * 执行HQL进行批量修改/删除操作.
     *
     * @param values 数量可变的参数,按顺序绑定.
     * @return 更新记录数.
     */
    public int batchExecuteHQL(final String hql, final Object... values) {
        return createHQLQuery(hql, values).executeUpdate();
    }

    /**
     * 执行SQL进行批量修改/删除操作.
     *
     * @param sql sql语句
     * @param values 数量可变的参数,按顺序绑定.
     * @return 更新记录数.
     */
    public int batchExecuteSQL(final String sql, final Object... values) {
        return createSQLQuery(sql, values).executeUpdate();
    }

    /**
     * 执行HQL进行批量修改/删除操作.
     *
     * @param values 命名参数,按名称绑定.
     * @return 更新记录数.
     */
    public int batchExecuteHQL(final String hql, final Map<String, ?> values) {
        return createHQLQuery(hql, values).executeUpdate();
    }

    /**
     * 执行SQL进行批量修改/删除操作.
     *
     * @param values 命名参数,按名称绑定.
     * @return 更新记录数.
     */
    public int batchExecuteSQL(final String sql, final Map<String, ?> values) {
        return createSQLQuery(sql, values).executeUpdate();
    }

    /**
     * 根据查询HQL与参数列表创建Query对象.
     * 与find()函数可进行更加灵活的操作.
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    public Query createHQLQuery(final String queryString, final Object... values) {
        Query query = getSession().createQuery(queryString);
        if (values != null) {
            for (int i = 0; i < values.length; i++) {
                query.setParameter(i, values[i]);
            }
        }
        return query;
    }

    /**
     * 根据查询SQL与参数列表创建Query对象.
     * 与find()函数可进行更加灵活的操作.
     * @param sqlQueryString sql语句
     *
     * @param values 数量可变的参数,按顺序绑定.
     */
    public Query createSQLQuery(final String sqlQueryString, final Object... values) {
        Query query = getSession().createSQLQuery(sqlQueryString);
        if (values != null) {
            for (int i = 0; i < values.length; i++) {
                query.setParameter(i, values[i]);
            }
        }
        return query;
    }

    /**
     * 根据查询HQL与参数列表创建Query对象.
     * 与find()函数可进行更加灵活的操作.
     *
     * @param values 命名参数,按名称绑定.
     */
    public Query createHQLQuery(final String queryString, final Map<String, ?> values) {
        Query query = getSession().createQuery(queryString);
        if (values != null) {
            query.setProperties(values);
        }
        return query;
    }

    /**
     * 根据查询SQL与参数列表创建Query对象.
     * 与find()函数可进行更加灵活的操作.
     * @param queryString SQL语句
     * @param values 命名参数,按名称绑定.
     */
    public Query createSQLQuery(final String queryString, final Map<String, ?> values) {
        Query query = getSession().createSQLQuery(queryString);
        if (values != null) {
            query.setProperties(values);
        }
        return query;
    }

    /**
     * 按Criteria查询对象列表.
     *
     * @param criterions 数量可变的Criterion.
     */
    @SuppressWarnings("unchecked")
    public List<T> find(final Criterion... criterions) {
        return createCriteria(criterions).list();
    }

    /**
     * 按Criteria查询唯一对象.
     *
     * @param criterions 数量可变的Criterion.
     */
    @SuppressWarnings("unchecked")
    public T findUnique(final Criterion... criterions) {
        return (T) createCriteria(criterions).uniqueResult();
    }

    /**
     * 根据Criterion条件创建Criteria.
     * 与find()函数可进行更加灵活的操作.
     *
     * @param criterions 数量可变的Criterion.
     */
    public Criteria createCriteria(final Criterion... criterions) {
        Criteria criteria = getSession().createCriteria(entityClass);
        for (Criterion c : criterions) {
            criteria.add(c);
        }
        return criteria;
    }

    /**
     * 初始化对象.
     * 使用load()方法得到的仅是对象Proxy, 在传到View层前需要进行初始化.
     * 如果传入entity, 则只初始化entity的直接属性,但不会初始化延迟加载的关联集合和属性.
     * 如需初始化关联属性,需执行:
     * Hibernate.initialize(user.getRoles())，初始化User的直接属性和关联集合.
     * Hibernate.initialize(user.getDescription())，初始化User的直接属性和延迟加载的Description属性.
     */
    public void initProxyObject(Object proxy) {
        Hibernate.initialize(proxy);
    }

    /**
     * Flush当前Session.
     */
    public void flush() {
        getSession().flush();
    }

    /**
     * 为Query添加distinct transformer.
     * 预加载关联对象的HQL会引起主对象重复, 需要进行distinct处理.
     */
    public Query distinct(Query query) {
        query.setResultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY);
        return query;
    }

    /**
     * 为Criteria添加distinct transformer.
     * 预加载关联对象的HQL会引起主对象重复, 需要进行distinct处理.
     */
    public Criteria distinct(Criteria criteria) {
        criteria.setResultTransformer(CriteriaSpecification.DISTINCT_ROOT_ENTITY);
        return criteria;
    }

    /**
     * 取得对象的主键名.
     */
    public String getIdName() {
        ClassMetadata meta = getSessionFactory().getClassMetadata(entityClass);
        return meta.getIdentifierPropertyName();
    }

    /**
     * 判断对象的属性值在数据库内是否唯一.
     *
     * 在修改对象的情景下,如果属性新修改的值(value)等于属性原来的值(orgValue)则不作比较.
     */
    public boolean isPropertyUnique(final String propertyName, final Object newValue, final Object oldValue) {
        if (newValue == null || newValue.equals(oldValue)) {
            return true;
        }
        Object object = findUniqueBy(propertyName, newValue);
        return (object == null);
    }

    @Override
    public void update(T object) {
        getSession().update(object);
    }

    @SuppressWarnings("unchecked")
    @Override
    public T load(ID id) {
        return (T) getSession().load(this.entityClass, id);
    }

    /**
     * 将list转化为数组
     * @param list
     * @return
     */
    protected Criterion[] list2Array(List<Criterion> list){
        if(list == null){
            return new Criterion[0];
        }
        Criterion[] result = new Criterion[list.size()];
        for(int i = 0; i < list.size(); i++){
            result[i] = list.get(i);
        }
        return result;
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        templateCache = new HashMap<String, StatementTemplate>();
        if(this.dynamicStatementBuilder == null){
            this.dynamicStatementBuilder = new NoneDynamicHibernateStatementBuilder();
        }
        dynamicStatementBuilder.init();
        Map<String,String> namedHQLQueries = dynamicStatementBuilder.getNamedHQLQueries();
        Map<String,String> namedSQLQueries = dynamicStatementBuilder.getNamedSQLQueries();
        Configuration configuration = new Configuration();
        configuration.setNumberFormat("#");
        StringTemplateLoader stringLoader = new StringTemplateLoader();
        for(Entry<String, String> entry : namedHQLQueries.entrySet()){
            stringLoader.putTemplate(entry.getKey(), entry.getValue());
            templateCache.put(entry.getKey(), new StatementTemplate(StatementTemplate.TYPE.HQL,new Template(entry.getKey(),new StringReader(entry.getValue()),configuration)));
        }
        for(Entry<String, String> entry : namedSQLQueries.entrySet()){
            stringLoader.putTemplate(entry.getKey(), entry.getValue());
            templateCache.put(entry.getKey(), new StatementTemplate(StatementTemplate.TYPE.SQL,new Template(entry.getKey(),new StringReader(entry.getValue()),configuration)));
        }
        configuration.setTemplateLoader(stringLoader);
    }

    protected String processTemplate(StatementTemplate statementTemplate,Map<String, ?> parameters){
        StringWriter stringWriter = new StringWriter();
        try {
            statementTemplate.getTemplate().process(parameters, stringWriter);
        } catch (Exception e) {
            LOGER.error("处理DAO查询参数模板时发生错误：{}",e.toString());
            throw new SysException(e);
        }
        return stringWriter.toString();
    }
}

我们的SimpleHibernateDAO实现了InitializingBean,在其afterProperties方法中我们将调用DynamicHibernateStatementBuilder把语句缓存起来
上层方法调用示例-这个已经非常类似ibatis了

public List<Resource> getDescendants(Long userId,String code) {
    Map<String, Object> values = new HashMap<String, Object>();
    values.put("userId", String.valueOf(userId));
    values.put("code", code);
    values.put("type", String.valueOf(ResourceTypeEnum.URL_RESOURCE.getType()));
    values.put("status", String.valueOf(ResourceStatusEnum.ACTIVE.getStatus()));
    return this.findByNamedQuery(new ResourceRowMapper(),"resource.getDescendants", values);
}