Multiple JdbcTemplate instances or not?

Question

From what I understand, both DataSource and JdbcTemplates are threadsafe, so you can configure a single instance of a JdbcTempla

Answer 1

Inherently spring is very subtle about best practices.

JdbcTemplate is thread-safe, notably lock-free (v4.2.4). Meaning it should not cause performance degradation when shared between concurrent threads*. Thus, there are no compelling reasons for more than one instance per data source.

Speculative note: this section is indeed confusing. Probably due to historical (evolutionary) reasons. Maybe spring had per dao policy in the past due to non thread safety or poor understading of domain at a time. Similar to xml based configuration "disaster". Nowadays spring renounce opinionated views and strive to be flexible instead. Which, unfortunately, led to bad design choices being acknowleged only covertly.

_{* measure don't guess}