If you are still looking for where Java is used, you don't have to look around, your side is. Open the Android phone, just open an App application, they are completely with the Java language, from Google to search for Android's API documentation, you will find it and Java's JDK documentation is amazingly similar. From two years ago when Android was just starting out, many Android apps today are developed by Java programmers and developers. Although Android utilizes a different JVM and a different wrapper, the code is still written in Java.
2. Server programs for financial services
Java is widely used in the financial services industry, where many multinational investment banks such as Goldman Sachs, Citigroup, Barclays, Standard Charted, and others use Java. ), as well as other banks, use Java to write front- and back-office electronic trading systems, settlement and confirmation systems, data processing projects, and other projects. In most cases, Java is used for server-side development, but most do not have any front-end, and they usually receive data from one server (the upper level), process it, and send it to another processing system (the next level of processing.) The Java Swing technology was designed to develop a visual interface client for traders to use, but with the rise of C# in the last few years, which has allowed programmers to dispense with cumbersome code in client-side development, C# is slowly replacing C#. However, with the rise of C# in recent years, programmers have been able to dispense with cumbersome code in client-side development, and C# is slowly replacing Swing as the mainstay of visual development.
3. Websites
Similarly, Java has been a major player in e-commerce as well as web development. There are many different frameworks that you can use to create web projects, SpringMVC, Struts 2.0, and frameworks. even simple servlets, jsp, and struts-based websites are popular for government projects. For example, medical ambulance, insurance, education, defense, and other different departmental websites are developed based on Java.
4. Software tools
Many popular software and development tools are written and developed in Java. For example, Eclipse, IneteliJIdea, and Netbans IDE, I think they are all written in Java. As mentioned above, Swing used to be very popular for visual desktop client development, most of them were used in financial services and investment banking, JavaFx has gained popularity, but it still can't replace Swing. now C# has almost replaced Swing in the field of financial development.
5. Trading Systems
Third-party trading systems, which are now a large part of the financial services industry, are also written in Java. For example, the popular trading platform Murex, which is also written in Java, connects to many bank front offices to provide services.
6. The J2ME system
With the advent of IOS and Android in recent years, which have pretty much taken over the J2ME market, there are still lower-end Nokia and Samsung phones that use J2ME. most mobile games and apps for cell phones in this era are written in MIDP and CLDC, which are part of J2ME, in order to adapt to Android. But J2ME is still popular in products like Blu-ray, magnetic cards, and set-top boxes. The reason communications apps are so popular is that Nokia's phones still support J2ME.
7. Embedded
Java has a lot of room for growth in the embedded space. On this platform, you can use Java technology (on smart cards or sensors) with as little as 130KB. Initially, Java was designed to work on embedded book devices. In fact, this is just one of those areas where it was a "write once, swim anywhere" project, and now it looks like it is.
8. Big data technologies
Hadoop and other big data processing technologies use Java or other things, such as Apache's Java-based HBase and Accumulo, and ElasticSearchas, but Java doesn't have much space in this space, as MongoDB is written in C++. MongoDB, for example, is written in C++. Overall, as long as Hadoop and ElasticSearchas are able to grow, Java still has the potential to capture a portion of this market.
9. The space for high-frequency transactions
The Java platform dramatically improves the platform's features and even though it compiles, it is also able to pass data as well as C++. It is for this reason that Java has become the language of choice for programmers writing trading platforms, because although the performance is not as good as in the native language, you can bypass its security, portability and maintainability, and run faster than an inexperienced C++ programmer would make the application much slower and unreliable.
10. Scientific applications
Today, Java is still the best choice for scientific applications, including natural language processing. The main reason for this is that Java is better than C++ or other languages in terms of security, portability, maintainability, and concurrency than other high-level languages.