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：

 1 package org.appfuse.service;

 2 

 3 import java.io.Serializable;

 4 import java.util.List;

 5 

 6 /**

 7  * Generic Manager that talks to GenericDao to CRUD POJOs.

 8  *

 9  * <p>Extend this interface if you want typesafe (no casting necessary) managers

10  * for your domain objects.

11  *

12  * @author <a href="mailto:[email protected]">Matt Raible</a>

13  *  Updated by jgarcia: added full text search + reindexing

14  * @param <T> a type variable

15  * @param <PK> the primary key for that type

16  */

17 public interface GenericManager<T, PK extends Serializable> {

18 

19     /**

20      * Generic method used to get all objects of a particular type. This

21      * is the same as lookup up all rows in a table.

22      * @return List of populated objects

23      */

24     List<T> getAll();

25 

26     /**

27      * Generic method to get an object based on class and identifier. An

28      * ObjectRetrievalFailureException Runtime Exception is thrown if

29      * nothing is found.

30      *

31      * @param id the identifier (primary key) of the object to get

32      * @return a populated object

33      * @see org.springframework.orm.ObjectRetrievalFailureException

34      */

35     T get(PK id);

36 

37     /**

38      * Checks for existence of an object of type T using the id arg.

39      * @param id the identifier (primary key) of the object to get

40      * @return - true if it exists, false if it doesn't

41      */

42     boolean exists(PK id);

43 

44     /**

45      * Generic method to save an object - handles both update and insert.

46      * @param object the object to save

47      * @return the updated object

48      */

49     T save(T object);

50 

51     /**

52      * Generic method to delete an object

53      * @param object the object to remove

54      */

55     void remove(T object);

56 

57     /**

58      * Generic method to delete an object based on class and id

59      * @param id the identifier (primary key) of the object to remove

60      */

61     void remove(PK id);

62 

63     /**

64      * Generic method to search for an object.

65      * @param searchTerm the search term

66      * @param clazz type of class to search for.

67      * @return a list of matched objects

68      */

69     List<T> search(String searchTerm, Class clazz);

70     /**

71      * Generic method to regenerate full text index of the persistent class T

72      */

73     void reindex();

74 

75     /**

76      * Generic method to regenerate full text index of all indexed classes

77      *

78      * @param async

79      *            true to perform the reindexing asynchronously

80      */

81     void reindexAll(boolean async);

82 }

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

1  public List<T> getAll(String order) {

2         Session sess = getSession();

3         Criteria criteria = sess.createCriteria(persistentClass);

4         criteria.addOrder(Order.desc(order));

5         System.out.println(criteria);

6         return criteria.list();

7     }

getAll

2. 自定义HQL语句的查询

1  public List<T> selectDataByHql(String hql) {

2          Session session = getSession();

3         Query query=session.createQuery(hql);

4         //执行查询，返回对象集合  

5         List<T> allClasses = query.list();

6         return allClasses;

7     }

selectDataByHql

3. 根据某一列字段精确匹配的数据，并可排序，比如State=1

1 public List<T> search(String property,Object value,String order) throws SearchException {

2         Session sess = getSession();

3         Criteria cri= sess.createCriteria(persistentClass); 

4         if(StringUtils.isNotBlank(order)){

5             cri.addOrder(Order.desc(order));

6         }

7         cri.add(Restrictions.eq(property,value));

8         return cri.list();

9     }

search

4. 自定义条件的查询

1 public List<T> search(Criterion query,String order) throws SearchException {

2         Session sess = getSession();

3         Criteria cri= sess.createCriteria(persistentClass); 

4         if(StringUtils.isNotBlank(order)){

5             cri.addOrder(Order.desc(order));

6         }

7         cri.add(query);

8         return cri.list();

9     }

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。