Mybatis源码之SimpleExecutor

/**
* @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);
handler.parameterize(stmt);
return stmt;
}

}