javax.servlet
Interface RequestDispatcher
public interface RequestDispatcher
This interface implements methods to forward a request or include
output from another (active) source such as another servlet.
A servlet can get an object that implements this interface from
the
ServletContext
by calling the
getRequestDispatcher()
method.
If the servlet engine can it should provide a (wrapper) object which
implements this interface when a servlet calls
getRequestDispatcher()
.
javax.servlet.ServletContext.getRequestDispatcher(java.lang.String)
forward
public void forward(ServletRequest request,
ServletResponse response)
throws ServletException,
IOException
Forwards a
ServletRequest
to the resource represented by the
RequestDispatcher
.
A servlet can call this method if it has not yet requested an
OutputStream
or a
Writer
from the
response
.
Note that the
RequestDispatcher
can change the
request
object before handing it to the target resource
depending on the string that was given to
getRequestDispatcher()
.
request
- the original requestresponse
- the response to which output should be written
include
public void include(ServletRequest request,
ServletResponse response)
throws ServletException,
IOException
Includes into the
ServletResponse
any output written by the
resource represented by the
RequestDispatcher
.
Note that the target resource can only use the
OutputStream
or
Writer
that the original caller uses. It can not set any
headers. Also note that any sessions should be started before calling
include.
The RequestDispatcher will not alter the original
request
before handing it to the target resource.
request
- the original requestresponse
- the original response