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Seriously.�Why Hibernate?

Java User Group

(Silesia)

http://ggajos.com | http://opentangerine.com

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Hypothesis

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Hibernate is always suboptimal solution

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but before ...

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SQL

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JDBC + SQL

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Experiment

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Hibernate vs JdbcTemplate

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Hibernate

Myths

  • No need to worry about SQL
  • DRY communication
  • Easy relation management
  • Easy query refactoring
  • No boilerplate
  • Type-safety
  • Easy migrations
  • Unification between databases
  • Easy scale
  • Easy cache
  • Easy multi-tenant

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JDBC Template + SQL

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JDBC Template + SQL

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JDBC Template + SQL

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JDBC Template + SQL

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JDBC Template + SQL

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Hibernate

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Idiomatic persistence

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Idiomatic persistence

source: http://stackoverflow.com/questions/5370482/whats-the-advantage-of-load-vs-get-in-hibernate

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​

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Idiomatic persistence

source: http://stackoverflow.com/questions/5862680/whats-the-advantage-of-persist-vs-save-in-hibernate

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Portability

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Portability²

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EntityManager vs SessionFactory

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EntityManager vs SessionFactory

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Gotchas

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I recommend watching full video: https://www.youtube.com/watch?v=UPWkpl5PL_w

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I recommend watching full video: https://www.youtube.com/watch?v=UPWkpl5PL_w

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I recommend watching full video: https://www.youtube.com/watch?v=UPWkpl5PL_w

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  • FlywayDB?
  • Migration files

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  • 3 levels of cache

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  • Concurrency
  • Scaling*

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Effort

SQL

Mappings and object abstractions

SQL

Boilerplate

SQL

Boilerplate

Hibernate

Plain JDBC

JDBC�Template

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Warning! Extra complex, we have TWO tables here! Only DBA experts please!

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Mapping

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Xml Mapping

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Vanilla Hibernate

  • Entity definition

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jOOQ

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jOOQ

no entity definition

no additional mapping def.

typesafe

no weird indexation

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Stored procedures [JDBC]

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Stored procedures [JPA]

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jOOQ

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Recap

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Hibernate

Myths

  • No need to worry about SQL
  • DRY communication
  • Easy relation management
  • Easy query refactoring
  • No boilerplate
  • Type-safety
  • Easy migrations
  • Unification between databases
  • Easy scale*
  • Easy cache
  • Easy multi-tenant

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Hibernate

Cons

  • HDD ;), Hibernate Driven Development,
  • One way ticket and long term suffering,
  • Bad SQL abstraction,
  • Multi SQL abstraction (Native query, HQL, detached criteria …)
  • Useless features (stamping, versioning, locking),
  • Generated schema = bad design,
  • 3 schemas
  • Gotchas! (ex. HQL LIMIT)

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Hibernate

Why?

  • Social proof
  • No reference
  • Never used anything else
  • Don’t know
  • Are there other solutions?
  • Why bother?
  • Naah...

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“An expert is a person who avoids small error as he sweeps on to the grand fallacy”

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- Benjamin Stolberg

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Survey

<External/>

link

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Hibernate

Pros

* I really tried hard to find ones (:

  • any ideas?

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Q/A

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Thanks!