 | Quick Introduction
 | Client Interaction
 | When a servlet accepts a call from a client, it receives
two objects:
| A ServletRequest,
which encapsulates the communication from the
client to the server. |
| A ServletResponse,
which encapsulates the communication from the
servlet back to the client. |
|
| ServletRequest and ServletResponse
are interfaces defined by the javax.servlet
package |
|
| The ServletRequest interface allows the servlet
access to:
| Information such as the names of the parameters passed
in by the client, the protocol (scheme) being used by
the client, and the names of the remote host that made
the request and the server that received it. |
| The input stream, ServletInputStream.
Servlets use the input stream to get data from clients
that use application protocols such as the HTTP POST and
PUT methods. |
Interfaces that extend ServletRequest interface
allow the servlet to retrieve more protocol-specific data. For
example, the HttpServletRequestinterface
contains methods for accessing HTTP-specific header information. |
| The ServletResponse interface gives the
servlet methods for replying to the client. It:
| Allows the servlet to set the content length and MIME
type of the reply |
| Provides an output stream, ServletOutputStream,
and a Writer through which the servlet can
send the reply data |
Interfaces that extend the ServletResponse
interface give the servlet more protocol-specific capabilities.
For example, the HttpServletResponseinterface
contains methods that allow the servlet to manipulate
HTTP-specific header information |
|
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