20+ Interactive Brokers Interview Questions and Answers

An immutable class in Java can be created by declaring the class as final, making all fields private and final, and not providing any setter methods.

• Declare the class as final to prevent inheritance

• Make all fields private and final to prevent modification

• Do not provide any setter methods to prevent changing the state

• Initialize all fields in the constructor

• Avoid returning mutable objects or references to internal mutable objects

Checked exceptions are checked at compile-time while unchecked exceptions are not.

• Checked exceptions are checked at compile-time and must be handled or declared in the method signature.

• Unchecked exceptions are not checked at compile-time and do not need to be handled or declared.

• Checked exceptions are usually used for recoverable errors while unchecked exceptions are used for unrecoverable errors.

• Examples of checked exceptions include IOException and SQLException while exampl...read more

Use Spring Data JPA to connect Spring Boot project with database.

• Add database configuration in application.properties or application.yml file

• Create entity classes annotated with @Entity and @Table

• Create repository interfaces extending JpaRepository

• Use @Autowired annotation to inject repository in services or controllers