Core Java courses can help you learn object-oriented programming, exception handling, multithreading, and Java Collections. You can build skills in writing efficient algorithms, debugging code, and developing user interfaces. Many courses introduce tools like Eclipse and IntelliJ IDEA, which are commonly used for coding and testing Java applications, along with frameworks such as Spring and Hibernate that facilitate web development and database management.

Amazon
Skills you'll gain: File I/O, Object Oriented Programming (OOP), Object Oriented Design, Java, Software Design, Maintainability, Debugging, Data Structures
Beginner · Course · 1 - 4 Weeks

Board Infinity
Skills you'll gain: Data Structures, Spring Boot, Restful API, Model View Controller, Spring Framework, Java Programming, Java, Authentications, Authorization (Computing), Microservices, Algorithms, Object Oriented Programming (OOP), Dependency Analysis
Advanced · Course · 1 - 4 Weeks

Oracle
Skills you'll gain: Java, Object Oriented Programming (OOP), Oracle Cloud, Computer Programming, Cloud Development, Integrated Development Environments, Development Environment
Beginner · Course · 1 - 4 Weeks

Skills you'll gain: JUnit, Restful API, Software Design, JSON, Software Testing
Intermediate · Course · 3 - 6 Months

EDUCBA
Skills you'll gain: Microservices, Spring Framework, Spring Boot, YAML, MongoDB, Application Deployment, NoSQL, Ajax, Software Architecture, Java, Scalability, Load Balancing, Restful API, Web Applications, File Management
Mixed · Course · 1 - 3 Months

Skills you'll gain: Identity and Access Management, Cloud Infrastructure, Google Cloud Platform, Infrastructure As A Service (IaaS), Cloud Computing, Cloud Management, Cloud Storage, Data Storage Technologies, NoSQL, System Monitoring, Encryption
Intermediate · Course · 1 - 3 Months

Skills you'll gain: Apache Maven, Java Programming, Java, Build Tools, Eclipse (Software), Database Application, Full-Stack Web Development, CI/CD, Web Applications, Application Servers, Software Configuration Management, Continuous Integration, Application Development, Business Logic, UI Components, Integrated Development Environments, Role-Based Access Control (RBAC), Automation, Software Design Patterns, Program Development
Beginner · Specialization · 3 - 6 Months

Skills you'll gain: Integrated Development Environments, Software Design Patterns
Beginner · Course · 1 - 4 Weeks

Skills you'll gain: Debugging, Java, Computer Programming, Algorithms, Program Development, Data Structures, Pseudocode, Integrated Development Environments, Object Oriented Programming (OOP), Computational Thinking
Beginner · Course · 1 - 3 Months

Skills you'll gain: Application Development, UI Components, Program Development, Maintainability
Beginner · Course · 1 - 4 Weeks

Skills you'll gain: JUnit, Software Documentation, Application Design, Software Testing, Performance Tuning, Data Persistence
Intermediate · Course · 1 - 4 Weeks

Skills you'll gain: Java Programming, Java, Object Oriented Programming (OOP), Oracle SQL Developer, Oracle Databases
Intermediate · Specialization · 1 - 3 Months