Pros and cons of JPA vs JDBC?

JPA (Java Persistence API) and JDBC (Java Database Connectivity) are two ways to work with databases in Java, differing in their level of abstraction.

Advantages of JPA:

• Abstraction from SQL, working with objects (ORM).
• Automatic management of object states (sessions, cache).
• Convenience when working with complex relationships and inheritance.
• Support for caching and lazy loading.

Disadvantages of JPA:

• Potentially lower performance due to abstractions.
• Complexity in configuration and understanding internal mechanisms.
• Sometimes difficult to optimize complex queries.

Advantages of JDBC:

• Direct control over SQL queries.
• High performance and predictability.
• Simplicity for simple operations.

Disadvantages of JDBC:

• A lot of boilerplate code.
• No automatic object mapping, manual handling of ResultSet needed.
• Harder to maintain and scale code as the project grows.

Example of using JDBC:

Connection conn = DriverManager.getConnection(url, user, password);
PreparedStatement stmt = conn.prepareStatement("SELECT * FROM users WHERE id = ?");
stmt.setInt(1, 10);
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
    System.out.println(rs.getString("name"));
}
rs.close();
stmt.close();
conn.close();

Example of JPA:

EntityManager em = entityManagerFactory.createEntityManager();
User user = em.find(User.class, 10);
System.out.println(user.getName());
em.close();

The choice depends on the project requirements: for complex business applications with many relationships, JPA is more convenient; for high-performance or simple tasks, JDBC.