The Servlet API provides the class javax.servlet.ServletContext
, which has methods that work with data stored in context. Any servlet can store Java objects in that context and other servlets can use them. The objects are stored with a String
key for uniqueness.
Here's how it works:
- Use setAttribute(String key, Object value) to store an attribute in context. key is the name of the attribute and value is the Java object to be stored.
- Use getAttribute(String key) to retreive the Java object corresponding to the value of key in context. If no object is found, null is returned.
- Remove attributes from context using remove(String key).
can be used in other ways besides data sharingfor instance, working with RequestDispatcher
or logging into the servlet log file.