Why some companies are still using Java 8?

There are several reasons why many companies are still using Java 8, despite newer versions being available: 

Long-Term Support (LTS): 

Java 8 was the last version to have "permanent" support from Oracle, while later versions have only six months before the next version is released. Although Oracle has introduced a new system where every three years a Long-Term Support (LTS) release will be provided, Java 11 being the first one, many organizations have been slow to move to this new model. 

Backward Compatibility: 

Some features introduced after Java 8, such as modularization with Project Jigsaw in Java 9, might break existing systems. Many companies prefer to stick with Java 8 to avoid the costs associated with making their existing code compatible with newer versions. 

Library and Framework Support: 

Not all libraries, tools, and frameworks are immediately updated to support newer Java versions, which may cause compatibility issues. 

Licensing and Commercial Support: 

Oracle changed its licensing terms starting with Java 11, which also impacts updates and support. Some organizations may find sticking with Java 8 or using alternative builds of later Java versions (like those provided by AdoptOpenJDK) more suitable for their needs. 

Cost of Upgrade: 

Upgrading to a newer Java version can be costly for a business. It involves not just replacing the runtime environment, but also testing to ensure that existing applications work correctly. 

It's worth noting that despite these reasons, many companies are working towards adopting newer Java versions due to the beneficial features they offer. These include enhanced language features, improved performance, and better security.