JPA Hibernate Alternatives: When JPA & Hibernate Aren't Right for Your Project

Hello, how are you?

Today we will talk about situations in which the use of the JPA/Hibernate is not recommended. Which alternatives do we have outside the JPA world?

What we will talk about:

• JPA/Hibernate problems

• Solutions to some of the JPA/Hibernate problems

• Criteria for choosing the frameworks described here

• Spring JDBC Template

• MyBatis

• Sormula

• sql2o

• Take a look at: jOOQ and Avaje

• Is a raw JDBC approach worth it?

• How can I choose the right framework?

• Final thoughts

I have created 4 CRUDs in my github using the frameworks mentioned in this post, you will find the URL at the beginning of each page.

I am not a radical that thinks that JPA is worthless, but I do believe that we need to choose the right framework for the each situation. If you do not know I wrote a JPA book (in Portuguese only) and I do not think that JPA is the silver bullet that will solve all the problems.

I hope you like the post. [=

JPA/Hibernate problems

There are times that JPA can do more harm than good. Below you will see the JPA/Hibernate problems and in the next page you will see some solutions to these problems:

• Composite Key: This, in my opinion, is the biggest headache of the JPA developers. When we map a composite key we are adding a huge complexity to the project when we need to persist or find a object in the database. When you use composite key several problems will might happen, and some of these problems could be implementation bugs.

• Legacy Database: A project that has a lot of business rules in the database can be a problem when wee need to invoke StoredProcedures or Functions.

• Artifact size: The artifact size will increase a lot if you are using the Hibernate implementation. The Hibernate uses a lot of dependencies that will increase the size of the generated jar/war/ear. The artifact size can be a problem if the developer needs to do a deploy in several remote servers with a low Internet band (or a slow upload). Imagine a project that in each new release it is necessary to update 10 customers servers across the country. Problems with slow upload, corrupted file and loss of Internet can happen making the dev/ops team to lose more time.

• Generated SQL: One of the JPA advantages is the database portability, but to use this portability advantage you need to use the JPQL/HQL language. This advantage can became a disadvantage when the generated query has a poor performance and it does not use the table index that was created to optimize the queries.

• Complex Query: That are projects that has several queries with a high level of complexity using database resources like: SUM, MAX, MIN, COUNT, HAVING, etc. If you combine those resources the JPA performance might drop and not use the table indexes, or you will not be able to use a specific database resource that could solve this problem.

• Framework complexity: To create a CRUD with JPA is very simples, but problems will appear when we start to use entities relationships, inheritance, cache, PersistenceUnit manipulation, PersistenceContext with several entities, etc. A development team without a developer with a good JPA experience will lose a lot of time with JPA ‘rules‘.

• Slow processing and a lot of RAM memory occupied: There are moments that JPA will lose performance at report processing, inserting a lot of entities or problems with a transaction that is opened for a long time.

After reading all the problems above you might be thinking: “Is JPA good in doing anything?”. JPA has a lot of advantages that will not be detailed here because this is not the post theme, JPA is a tool that is indicated for a lot of situations. Some of the JPA advantages are: database portability, save a lot of the development time, make easier to create queries, cache optimization, a huge community support, etc.

In the next page we will see some solutions for the problems detailed above, the solutions could help you to avoid a huge persistence framework refactoring. We will see some tips to fix or to workaround the problems described here.