What do you mean by Spring Java Based Configuration?

Spring configuration files are XML files. These files contain the information of classes and describe how these classes can be configured and merged to each other. Java based configuration is a feature which enables the user to write most of their spring configuration without using XML. Instead, they are written with the help Java-based annotations.

For example, Java Annotation @Configuration is used to indicate that Spring IoC container can use the class, which is a source of bean definitions.