Java has been a widely used programming language for a long time in various fields. Java and its libraries have been frequently updated for various reasons including bugs, change requests, performance and usability requirements and so on. In this paper, we examine how these changes affect the use of Java and analyze trends in its usage. As a data source, we use the Stack Overflow public dataset which is the largest online Q&A site about software technologies. We firstly employ a practical approach to extract the Javarelated posts from the Stack Overflow dataset using cosine similarity and compare it with previous works. We then apply Latent Dirichlet Allocation (LDA) to the corpus for topic modelling. We divided the data set into two-year periods to obtain consistent clusters. After obtaining main topics, we examine topics and keywords on a two-year basis. Finally, unlikely previous works, we manually classify topics into two as "domain-specific" and "development environment" and investigate tendencies of these classes to change in both the short term and the long term.