Do I understand it right that reflection does not seem to be the bottleneck? In that case,
you should probably play with the fetch size a bit (see the
setFetchSize() method in the
Statement interface). If your goal is to read the whole resultset as quickly as possible, try really high fetch size. One
word of warning though: I've got exceptions with high fetch sizes in Oracle (the problem seemed to be related to the total amount of data fetched at once, so narrow tables could have higher fetch size than wide ones), so
test the setting thoroughly and probably make them configurable too.
If you want to avoid reflection for whatever reason, I might suggest an approach I'm using on one project where we also avoided ORM frameworks. I've written a utility which analyzes table creation SQL script (with syntax tightened up to make the parsing easier) and creates POJO and DAO classes and interfaces for around a hundred tables based on the SQL scripts. Our schema changes a lot and my primary objective was to have a single authoritative source of schema structure so I wouldn't have to propagate changes manually to Java sources. (Simpler approach might employ some XML to describe the schema and generate the table creation scripts from this XML as well. I've missed on this.)
I believe similar functionality is available in various ORM frameworks, ie. you could have these classes generated from your schema. I investigated this briefly, but then decided for homebrewed solution as we also create schema documentation this way.
Edit: one more thought: ORM does not employ some magic here, so there is no reason why pure JDBC solution could not be as fast as ORM. To the contrary, as ORM is a generic solution, JDBC gives you more leeway and at least in some cases will allow you to do things faster than ORM (probably). If ORM seems faster to you, it is probably because it has fine-tuned some parameters, such as fetch-size, against a database you're using.
Also, make sure to use read-only, forward-only resultset. They might not be faster than other flavors, but certainly they won't be any slower.