Appfuse：扩展自己的GenericManager

通过代码生成机制的appfuse访问数据都通过GenericManager来实现，GenericManager默认提供了以下几个方法：

 package org.appfuse.service;

 import java.io.Serializable;
 import java.util.List;

 /**
  * Generic Manager that talks to GenericDao to CRUD POJOs.
  *
  * <p>Extend this interface if you want typesafe (no casting necessary) managers
  * for your domain objects.
  *
  * @author <a href="mailto:matt@raibledesigns.com">Matt Raible</a>
  *  Updated by jgarcia: added full text search + reindexing
  * @param <T> a type variable
  * @param <PK> the primary key for that type
  */
 public interface GenericManager<T, PK extends Serializable> {

     /**
      * Generic method used to get all objects of a particular type. This
      * is the same as lookup up all rows in a table.
      * @return List of populated objects
      */
     List<T> getAll();

     /**
      * Generic method to get an object based on class and identifier. An
      * ObjectRetrievalFailureException Runtime Exception is thrown if
      * nothing is found.
      *
      * @param id the identifier (primary key) of the object to get
      * @return a populated object
      * @see org.springframework.orm.ObjectRetrievalFailureException
      */
     T get(PK id);

     /**
      * Checks for existence of an object of type T using the id arg.
      * @param id the identifier (primary key) of the object to get
      * @return - true if it exists, false if it doesn't
      */
     boolean exists(PK id);

     /**
      * Generic method to save an object - handles both update and insert.
      * @param object the object to save
      * @return the updated object
      */
     T save(T object);

     /**
      * Generic method to delete an object
      * @param object the object to remove
      */
     void remove(T object);

     /**
      * Generic method to delete an object based on class and id
      * @param id the identifier (primary key) of the object to remove
      */
     void remove(PK id);

     /**
      * Generic method to search for an object.
      * @param searchTerm the search term
      * @param clazz type of class to search for.
      * @return a list of matched objects
      */
     List<T> search(String searchTerm, Class clazz);
     /**
      * Generic method to regenerate full text index of the persistent class T
      */
     void reindex();

     /**
      * Generic method to regenerate full text index of all indexed classes
      *
      * @param async
      *            true to perform the reindexing asynchronously
      */
     void reindexAll(boolean async);
 }

GenericManager

通常我们用getAll()访问表中所有的数据，可惜无排序；用search(String searchTerm, Class clazz)来过滤数据，可惜不能自定义条件，只能全字段搜索。

下面是我在开发过程中扩展出来的几个方法，直接附上GenericDaoHibernate中的实现，各层的声明就没再累赘。

1. 自定义排序的getAll

  public List<T> getAll(String order) {
         Session sess = getSession();
         Criteria criteria = sess.createCriteria(persistentClass);
         criteria.addOrder(Order.desc(order));
         System.out.println(criteria);
         return criteria.list();
     }

getAll

2. 自定义HQL语句的查询

  public List<T> selectDataByHql(String hql) {
          Session session = getSession();
         Query query=session.createQuery(hql);
         //执行查询，返回对象集合
         List<T> allClasses = query.list();
         return allClasses;
     }

selectDataByHql

3. 根据某一列字段精确匹配的数据，并可排序，比如State=1

 public List<T> search(String property,Object value,String order) throws SearchException {
         Session sess = getSession();
         Criteria cri= sess.createCriteria(persistentClass);
         if(StringUtils.isNotBlank(order)){
             cri.addOrder(Order.desc(order));
         }
         cri.add(Restrictions.eq(property,value));
         return cri.list();
     }

search

4. 自定义条件的查询

 public List<T> search(Criterion query,String order) throws SearchException {
         Session sess = getSession();
         Criteria cri= sess.createCriteria(persistentClass);
         if(StringUtils.isNotBlank(order)){
             cri.addOrder(Order.desc(order));
         }
         cri.add(query);
         return cri.list();
     }

search

有人可能疑问为啥定义了4，还要再定义2呢，只能说编码风格的问题，我喜欢用4的方式，但有人喜欢HQL语句，觉得更加直观。