What is the difference between Java filters and interceptors?

There are some differences in implementation and usage between filters and interceptors in Java, but both are used to handle requests.

1. Filters are based on function callbacks, while interceptors are based on aspect-oriented programming. Filters handle requests by calling the appropriate methods before or after the target resource is reached, allowing for pre-processing before reaching the controller or post-processing before the controller returns a response. On the other hand, interceptors intercept and handle requests by weaving code around the target method.
2. Filters are based on the Servlet specification, while interceptors are based on the Spring framework. Filters are executed in the Servlet container and can process web resources, such as filtering requests and modifying responses. Interceptors, on the other hand, are executed in the Spring container and can handle controllers in Spring MVC, such as processing request parameters and modifying return results.
3. Filter configuration is done in the web.xml file, whereas interceptor configuration is done in the Spring configuration file. Filter configuration is achieved by using and tags in the web.xml file. Interceptor configuration is achieved by using the tag in the Spring configuration file.
4. Filters can be shared among multiple Servlets, while interceptors can only be shared within the same Spring container.

In general, filters are used to process web resources based on the Servlet specification, while interceptors are used to process Controllers in Spring MVC based on the Spring framework. Their usage and configuration methods also differ.