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Interface javax.servlet.ServletContext

public interface ServletContext
The ServletContext interface gives servlets access to information about their environment, and allows them to log significant events. Servlet writers decide what data to log. The interface is implemented by services, and used by servlets. Different virtual hosts should have different servlet contexts.

Servlets get the ServletContext object via the getServletContext method of ServletConfig. The ServletConfig object is provided to the servlet at initialization, and is accessible via the servlet's getServletConfig method.

See Also:
getServletConfig, getServletContext

Method Index

o getAttribute(String)
Returns the value of the named attribute of the network service, or null if the attribute does not exist.
o getMimeType(String)
Returns the mime type of the specified file, or null if not known.
o getRealPath(String)
Applies alias rules to the specified virtual path and returns the corresponding real path.
o getServerInfo()
Returns the name and version of the network service under which the servlet is running.
o getServlet(String)
Returns the servlet of the specified name, or null if not found.
o getServlets()
Returns an enumeration of the Servlet objects in this server.
o log(String)
Writes the given message string to the servlet log file.

Methods

o getServlet 
 public abstract Servlet getServlet(String name) throws ServletException
Returns the servlet of the specified name, or null if not found. When the servlet is returned it is initialized and ready to accept service requests.

Parameters:
name - the name of the desired servlet
Throws: ServletException
if the servlet could not be initialized
o getServlets 
 public abstract Enumeration getServlets()
Returns an enumeration of the Servlet objects in this server. Only servlets that are accessible (i.e., from the same namespace) will be returned. The enumeration always includes the servlet itself.

o log 
 public abstract void log(String msg)
Writes the given message string to the servlet log file. The name of the servlet log file is server specific; it is normally an event log.

Parameters:
msg - the message to be written
o getRealPath 
 public abstract String getRealPath(String path)
Applies alias rules to the specified virtual path and returns the corresponding real path. For example, in an HTTP servlet, this method would resolve the path against the HTTP service's docroot. Returns null if virtual paths are not supported, or if the translation could not be performed for any reason.

Parameters:
path - the virtual path to be translated into a real path
o getMimeType 
 public abstract String getMimeType(String file)
Returns the mime type of the specified file, or null if not known.

Parameters:
file - name of the file whose mime type is required
o getServerInfo 
 public abstract String getServerInfo()
Returns the name and version of the network service under which the servlet is running. Same as the CGI variable SERVER_SOFTWARE.

o getAttribute 
 public abstract Object getAttribute(String name)
Returns the value of the named attribute of the network service, or null if the attribute does not exist. This method allows access to additional information about the service, not already provided by the other methods in this interface. Attribute names should follow the same convention as package names. The package names java.* and javax.* are reserved for use by Javasoft, and com.sun.* is reserved for use by Sun Microsystems.

Parameters:
name - the name of the attribute whose value is required
Returns:
the value of the attribute, or null if the attribute does not exist. 
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