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+- Mybatis初始化过程
+	- 通过InputStream来获取配置文件
+	- ClassLoaderWarpper中的getResourceAsStream可以根据配置的resoutce来获取到配置文件的输入六
+	- 使用ClassLoader是因为类加载器可具有读取外部资源的能力
+	- ![image.png](../assets/image_1714227673997_0.png)
+	- 读取到配置文件后传入SqlSessionFactoryBuilder，内部使用XMLConfigBuilder的parse方法读取配置并set到一个configuration变量中返回一个Configuration对象
+	- ![image.png](../assets/image_1714228148958_0.png)
+	- 使用build方法创建一个DefaultSqlSessionFactory并返回
+	- 在其中会创建一个SqlSession，其中会创建事务工厂之类的
+	- ![image.png](../assets/image_1714228719703_0.png)
+	- 将mapper类传入session，通过session.getMapper方法在mapperRegistry获取到一个该mapper类的代理类MapperProxy
+	- 执行时会执行该代理类的invoke方法
+	- ![image.png](../assets/image_1714230626595_0.png)
+	- 触发mapperMethod的execute方法
+	- ```java
+	  public Object execute(SqlSession sqlSession, Object[] args) {
+	    Object result;
+	    switch (command.getType()) {
+	      case *INSERT*: {
+	        Object param = method.convertArgsToSqlCommandParam(args);
+	        result = rowCountResult(sqlSession.insert(command.getName(), param));
+	        break;
+	      }
+	      case *UPDATE*: {
+	        Object param = method.convertArgsToSqlCommandParam(args);
+	        result = rowCountResult(sqlSession.update(command.getName(), param));
+	        break;
+	      }
+	      case *DELETE*: {
+	        Object param = method.convertArgsToSqlCommandParam(args);
+	        result = rowCountResult(sqlSession.delete(command.getName(), param));
+	        break;
+	      }
+	      case *SELECT*:
+	        if (method.returnsVoid() && method.hasResultHandler()) {
+	          executeWithResultHandler(sqlSession, args);
+	          result = null;
+	        } else if (method.returnsMany()) {
+	          result = executeForMany(sqlSession, args);
+	        } else if (method.returnsMap()) {
+	          result = executeForMap(sqlSession, args);
+	        } else if (method.returnsCursor()) {
+	          result = executeForCursor(sqlSession, args);
+	        } else {
+	          Object param = method.convertArgsToSqlCommandParam(args);
+	          result = sqlSession.selectOne(command.getName(), param);
+	          if (method.returnsOptional()
+	              && (result == null || !method.getReturnType().equals(result.getClass()))) {
+	            result = Optional.*ofNullable*(result);
+	          }
+	        }
+	        break;
+	      case *FLUSH*:
+	        result = sqlSession.flushStatements();
+	        break;
+	      default:
+	        throw new BindingException("Unknown execution method for: " + command.getName());
+	    }
+	    if (result == null && method.getReturnType().isPrimitive() && !method.returnsVoid()) {
+	      throw new BindingException("Mapper method '" + command.getName()
+	          + " attempted to return null from a method with a primitive return type (" + method.getReturnType() + ").");
+	    }
+	    return result;
+	  }
+	  ```
+	- 会根据不同的语句类型执行不同的execute方法，查询list会执行executeForMany方法
+	- ```java
+	  private <E> Object executeForMany(SqlSession sqlSession, Object[] args) {
+	    List<E> result;
+	    Object param = method.convertArgsToSqlCommandParam(args);
+	    if (method.hasRowBounds()) {
+	      RowBounds rowBounds = method.extractRowBounds(args);
+	      result = sqlSession.selectList(command.getName(), param, rowBounds);
+	    } else {
+	      result = sqlSession.selectList(command.getName(), param);
+	    }
+	    *// issue #510 Collections & arrays support
+	  *  if (!method.getReturnType().isAssignableFrom(result.getClass())) {
+	      if (method.getReturnType().isArray()) {
+	        return convertToArray(result);
+	      } else {
+	        return convertToDeclaredCollection(sqlSession.getConfiguration(), result);
+	      }
+	    }
+	    return result;
+	  }
+	  ```
+	- selectList获取MappedStatement，再执行executor.query方法
+	- ```java
+	  @Override
+	  public <E> List<E> query(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler) throws SQLException {
+	    BoundSql boundSql = ms.getBoundSql(parameterObject);
+	    CacheKey key = createCacheKey(ms, parameterObject, rowBounds, boundSql);
+	    return query(ms, parameterObject, rowBounds, resultHandler, key, boundSql);
+	  }
+	  ```
+	- BoundSql为去掉if，where标签的sql语句，Cachekey为缓存key
+	- 查询时先从缓存获取，获取不到或list为null就执行delegate.query方法查询
+	- 检查executor是否被关闭，是否清理缓存
+	- 通过queryFromDatabase，先在缓存中放一个占位符，接着使用doQuery方法查询，然后把缓存中的占位符换成真正的结果
+	- ```java
+	  private <E> List<E> queryFromDatabase(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler, CacheKey key, BoundSql boundSql) throws SQLException {
+	    List<E> list;
+	    localCache.putObject(key, *EXECUTION_PLACEHOLDER*);
+	    try {
+	      list = doQuery(ms, parameter, rowBounds, resultHandler, boundSql);
+	    } finally {
+	      localCache.removeObject(key);
+	    }
+	    localCache.putObject(key, list);
+	    if (ms.getStatementType() == StatementType.*CALLABLE*) {
+	      localOutputParameterCache.putObject(key, parameter);
+	    }
+	    return list;
+	  }
+	  ```
+	- 执行doQuery方法，为BatchExecutor类的方法
+	- ```java
+	  public <E> List<E> doQuery(MappedStatement ms, Object parameterObject, RowBounds rowBounds, ResultHandler resultHandler, BoundSql boundSql)
+	      throws SQLException {
+	    Statement stmt = null;
+	    try {
+	      flushStatements();
+	      Configuration configuration = ms.getConfiguration();
+	      StatementHandler handler = configuration.newStatementHandler(wrapper, ms, parameterObject, rowBounds, resultHandler, boundSql);
+	      Connection connection = getConnection(ms.getStatementLog());
+	      stmt = handler.prepare(connection, transaction.getTimeout());
+	      handler.parameterize(stmt);
+	      return handler.query(stmt, resultHandler);
+	    } finally {
+	      closeStatement(stmt);
+	    }
+	  }
+	  ```
+	- 通过Statement执行静态语句获取结果
+	- 执行的是PrepareStatementHandler.query方法，获取结果后交给ResultSetHandler处理，通过resultMap将值赋值给对象