mybatis SqlSessionFactory工厂模式

一、工厂方法模式实现sqlsession

（从别人博客复制的图）

 1.Sqlsession接口

在sqlsession接口中包含了所有可能执行的sql语句。而Defaultsqlsession是他的实现类，实现了其中的方法。

 

 1 public interface SqlSession extends Closeable {
 2 
 3   /**
 4    * Retrieve a single row mapped from the statement key
 5    * @param <T> the returned object type
 6    * @param statement
 7    * @return Mapped object
 8    */
 9   <T> T selectOne(String statement);
10 /**
11    * Retrieve a list of mapped objects from the statement key and parameter.
12    * @param <E> the returned list element type
13    * @param statement Unique identifier matching the statement to use.
14    * @return List of mapped object
15    */
16   <E> List<E> selectList(String statement);

 

 

 

 

2.DefaultSqlSession

 1 public class DefaultSqlSession implements SqlSession {
 2 
 3   private Configuration configuration;
 4   private Executor executor;
 5 
 6   private boolean dirty;
 7 
 8  public <E> List<E> selectList(String statement, Object parameter, RowBounds rowBounds) {
 9     try {
10       MappedStatement ms = configuration.getMappedStatement(statement);
11       List<E> result = executor.query(ms, wrapCollection(parameter), rowBounds, Executor.NO_RESULT_HANDLER);
12       return result;
13     } catch (Exception e) {
14       throw ExceptionFactory.wrapException("Error querying database.  Cause: " + e, e);
15     } finally {
16       ErrorContext.instance().reset();
17     }
18   }

3.SqlSessionFactory接口

sqlsessionfactory类中有opsession方法，用来创建sqlsession。

4、DefaultSqlSessionFactory类实现了SqlSessionFactory

 

posted @ 2017-09-13 13:58  LookOutTheBush  阅读(715)  评论(0)  编辑  收藏  举报