Servlet Container

The servlet container is a part of a web server or application server that provides the network services over which requests and responses are sent, decodes MIME based requests, and formats MIME based responses. A servlet container also contains and manages servlets through their lifecycle. A servlet container can be built into a host web server, or installed as an addon component to a Web Server via that server’s native extension API. Servlet containers can also be built into or possibly installed into web-enabled application servers. All servlet containers must support HTTP as a protocol for requests and responses, but additional request/response based protocols such as HTTPS (HTTP over SSL) may be supported. The minimum required version of the HTTP specification that a container must implement is HTTP/1.0. It is strongly suggested that containers implement the HTTP/1.1 specification as well.

A Servlet Container may place security restrictions on the environment in which a servlet executes. In a JavaTM 2 Platform, Standard Edition 1.2 (J2SETM) or Java 2 Platform, Enterprise Edition 1.3 (J2EE) environment, these restrictions should be placed using the permission architecture defined by the Java 2 platform.
For example, high-end application servers may limit the creation of a Thread object, to insure that other components of the container are not negatively impacted. J2SE 1.2 is the minimum version of the underlying Java platform with which servlet containers must be built.