Java.Hibernate.Beginner.Which connection pool hibernte uses ?

✅ How does Hibernate handle database connections? Does it use HikariCP under the hood?

Answer:
🔹 How Hibernate manages connections:

• Hibernate doesn’t open raw database connections manually each time you run a query. Instead, it uses a connection pool to efficiently reuse existing connections.
• The pool manages a fixed number of database connections that are checked out when needed and returned when you close the Session.

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🔹 Connection providers:

• Hibernate can use different ConnectionProvider implementations to manage connections:
  • A direct JDBC connection (inefficient, rarely used in production).
  • A third-party connection pool, like C3P0, Apache DBCP, or HikariCP.
  • A connection pool managed by an application server (e.g., a JNDI datasource in a Java EE environment).

🔹 Does Hibernate use HikariCP by default?

• Since Hibernate 5.2.10, HikariCP became the default connection pool when using the official Hibernate libraries together with JPA.
• If you don’t explicitly configure a connection pool, Hibernate will automatically use HikariCP as its ConnectionProvider, provided the HikariCP library is on the classpath (e.g., it’s included by default if you use Spring Boot with spring-boot-starter-data-jpa).

🔹 How to configure HikariCP with Hibernate:

• In Spring Boot, Hibernate inherits the datasource configuration, and spring.datasource.hikari.* properties directly configure HikariCP.
• If you’re configuring Hibernate manually, you’d include HikariCP in your dependencies and set properties like:

hibernate.connection.provider_class=org.hibernate.hikaricp.internal.HikariCPConnectionProvider
hibernate.hikari.maximumPoolSize=20
hibernate.hikari.minimumIdle=5

✅ Key takeaway:
Hibernate doesn’t directly manage raw connections; it delegates connection management to a connection pool — and HikariCP is the recommended and often default pool for modern Hibernate setups.