Mybatis执行SimpleExecutor（三）

ゝ一世哀愁。 2022-03-08 02:26 179阅读 0赞

SimpleExecutor通过类名可以看出，它是一个简单的执行类，并不会做一些处理就执行sql，源码及分析如下：

/**
     * @author Clinton Begin
     */
    public class SimpleExecutor extends BaseExecutor {
     
      public SimpleExecutor(Configuration configuration, Transaction transaction) {
        super(configuration, transaction);
      }
     
      @Override
      public int doUpdate(MappedStatement ms, Object parameter) throws SQLException {
        Statement stmt = null;
        try {
    	  //获得配置文件对象
          Configuration configuration = ms.getConfiguration();
    	  //获得statementHandler里面有statement，来处理
          StatementHandler handler = configuration.newStatementHandler(this, ms, parameter, RowBounds.DEFAULT, null, null);
          stmt = prepareStatement(handler, ms.getStatementLog());
    	  //最终是一个statement进行处理
          return handler.update(stmt);
        } finally {
          closeStatement(stmt);
        }
      }
     
      @Override
      public <E> List<E> doQuery(MappedStatement ms, Object parameter, RowBounds rowBounds, ResultHandler resultHandler, BoundSql boundSql) throws SQLException {
        Statement stmt = null;
        try {
    	  //获得配置文件对象
          Configuration configuration = ms.getConfiguration();
    	  //获得statementHandler里面有statement，来处理
          StatementHandler handler = configuration.newStatementHandler(wrapper, ms, parameter, rowBounds, resultHandler, boundSql);
    	  //获得statement
          stmt = prepareStatement(handler, ms.getStatementLog());
    	  //最终是一个statement进行处理
          return handler.<E>query(stmt, resultHandler);
        } finally {
          closeStatement(stmt);
        }
      }
     
      @Override
      public List<BatchResult> doFlushStatements(boolean isRollback) throws SQLException {
        return Collections.emptyList();
      }
     
      private Statement prepareStatement(StatementHandler handler, Log statementLog) throws SQLException {
        Statement stmt;
        Connection connection = getConnection(statementLog);
        stmt = handler.prepare(connection);
    	//将Statement转为PrepareStatement
        handler.parameterize(stmt);
        return stmt;
      }
     
    }

本文原文地址：[https://blog.csdn.net/qq924862077/article/details/52641337][https_blog.csdn.net_qq924862077_article_details_52641337]

[https_blog.csdn.net_qq924862077_article_details_52641337]: https://blog.csdn.net/qq924862077/article/details/52641337