Below are companies that us the Java programming language:

Google: Google uses Java extensively in its products and services. For example, the Android operating system, which powers millions of mobile devices worldwide, is primarily built using Java. Additionally, many of Google's web applications and backend systems are developed using Java.

Amazon: Java is a fundamental part of Amazon's technology stack. It is used for building the backend infrastructure that powers Amazon's e-commerce platform and various web services like Amazon Web Services (AWS). Java's scalability and reliability make it suitable for handling high traffic and complex systems.

Netflix: Netflix relies heavily on Java for its video streaming platform. Java is used for developing the backend systems that manage user accounts, handle content delivery, and provide personalized recommendations. Netflix also leverages Java's concurrency features to ensure smooth streaming experiences.

Airbnb: Java is used at Airbnb for developing the backend services that power their online marketplace for lodging and accommodations. It is used to handle booking requests, manage databases, and handle complex business logic. Java's scalability and stability are crucial for supporting Airbnb's large user base.

Uber: Java is utilized in several parts of Uber's technology stack. It is used for building the backend systems that handle ride requests, driver allocation, and real-time tracking. Java's performance and reliability are vital for ensuring a seamless and efficient experience for Uber's users.

LinkedIn: LinkedIn, a popular professional networking platform, relies on Java for its backend infrastructure. Java is used for handling user authentication, data storage, and providing various features like job recommendations and messaging services. The scalability and robustness of Java support LinkedIn's extensive user base.

Twitter: Java plays a significant role in Twitter's technology stack. It is used for developing backend services that handle tweet storage, user interactions, and real-time data processing. Java's concurrency capabilities are crucial for handling the high volume of tweets and user interactions on the platform.