Following code style conventions in software projects is essential for maintaining overall code quality. Adhering to these conventions improves maintainability, understandability, and extensibility. Additionally, following best practices during software development enhances performance and reduces the likelihood of errors. This paper investigates the adoption and evolution of code style and programming practices in open-source Java projects. We analyze 1,000 popular open-source Java repositories on GitHub to examine the prevalence of these practices and identify the most common violations. Additionally, we study a subset of active repositories on a monthly basis to track changes in adherence to coding standards over time. The results provide valuable insights into the adoption of code style and programming practices, highlighting key areas for improvement in the open- source development community. Furthermore, the paper identifies important lessons learned and suggests future directions for improving code quality in Java projects.