Java courses can help you learn object-oriented programming, data structures, exception handling, and multithreading concepts. 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.

EDUCBA
Skills you'll gain: IntelliJ IDEA, Apache Maven, Build Tools, Integrated Development Environments, Software Development Tools, Version Control, Git (Version Control System), Development Environment, Computer Graphics, Debugging, Scripting Languages, Visualization (Computer Graphics), Databases, Relational Databases
Intermediate · Course · 1 - 4 Weeks

Johns Hopkins University
Skills you'll gain: Apache Hadoop, Big Data, Apache Hive, Apache Spark, NoSQL, Data Infrastructure, File Systems, Data Processing, Data Management, Analytics, Data Science, Databases, SQL, Query Languages, Data Manipulation, Java, Data Structures, Distributed Computing, Scripting Languages, Performance Tuning
Intermediate · Specialization · 3 - 6 Months

Skills you'll gain: Blockchain, User Interface (UI), Bootstrap (Front-End Framework), User Interface (UI) Design, Development Environment, Front-End Web Development, Debugging, Web Development Tools, Full-Stack Web Development, Animations, Web Applications, FinTech, Application Development, Javascript, Emerging Technologies, Virtual Machines, Software Testing, Software Development Tools, Computer Programming Tools, Program Development
Intermediate · Specialization · 3 - 6 Months

École Polytechnique Fédérale de Lausanne
Skills you'll gain: Scala Programming, Data Structures, Distributed Computing, Algorithms, Performance Tuning, Functional Design, Machine Learning Algorithms, Performance Testing, Computer Programming
Intermediate · Course · 1 - 4 Weeks

Skills you'll gain: Restful API, Spring Boot, API Design, Spring Framework, JSON, Object-Relational Mapping, Integration Testing, Data Modeling, Server Side, Software Architecture, Data Persistence, Data Validation
Mixed · Course · 1 - 4 Weeks

Skills you'll gain: Javascript, JSON, Web Applications, Computer Programming, Application Design, Scripting Languages, Hypertext Markup Language (HTML), Cascading Style Sheets (CSS), Prototyping, Context Management
Beginner · Specialization · 3 - 6 Months

Skills you'll gain: JUnit, Apache Maven, Unit Testing, Spring Framework, Spring Boot, Restful API, API Testing, Software Testing, Test Case, Gradle, Software Development Tools, Integration Testing, Mockups, JSON, Authentications
Intermediate · Course · 1 - 3 Months

Scrimba
Skills you'll gain: React Redux, React.js, JavaScript Frameworks, Javascript, Web Development Tools, Middleware, Web Development
Intermediate · Course · 1 - 4 Weeks

Skills you'll gain: Extract, Transform, Load, Apache Spark, Data Pipelines, PySpark, Apache Hadoop, Data Transformation, MySQL, Data Manipulation, Java Platform Enterprise Edition (J2EE), Data Import/Export, Data Persistence, Development Environment, Software Installation
Mixed · Course · 1 - 4 Weeks

Board Infinity
Skills you'll gain: Responsive Web Design, Restful API, User Interface (UI) Design, Application Programming Interface (API), Web Development Tools, Database Design, HTML and CSS, API Design, Front-End Web Development, MongoDB, Javascript, Postman API Platform, Bootstrap (Front-End Framework), React.js, UI Components, Ajax, Database Management, OAuth, Frontend Integration, Authentications
Intermediate · Specialization · 1 - 3 Months

Skills you'll gain: Server Side, Web Development, Web Scraping, Web Applications, Back-End Web Development, Integration Testing, Python Programming, Web Services, Extensible Markup Language (XML), Package and Software Management, Development Testing, Unit Testing, Performance Tuning, Cross Platform Development, Hypertext Markup Language (HTML), Debugging
Mixed · Course · 1 - 4 Weeks

Skills you'll gain: Authentications, OAuth, API Testing, Restful API, Application Programming Interface (API), JSON, Test Automation, Data Validation, Extensible Markup Language (XML), Mockups, Test Tools, Simple Object Access Protocol (SOAP), Virtualization, Debugging
Intermediate · Course · 1 - 3 Months