+ * There is one context per "web application" per Java Virtual Machine. (A
+ * "web application" is a collection of servlets and content installed under a
+ * specific subset of the server's URL namespace such as /catalog
+ * and possibly installed via a .war file.)
+ *
+ * In the case of a web application marked "distributed" in its deployment + * descriptor, there will be one context instance for each virtual machine. In + * this situation, the context cannot be used as a location to share global + * information (because the information won't be truly global). Use an external + * resource like a database instead. + *
+ * The ServletContext object is contained within the
+ * {@link ServletConfig} object, which the Web server provides the servlet when
+ * the servlet is initialized.
+ *
+ * @see Servlet#getServletConfig
+ * @see ServletConfig#getServletContext
+ */
+public interface ServletContext {
+
+ public static final String TEMPDIR = "javax.servlet.context.tempdir";
+
+ /**
+ * @since Servlet 3.0
+ */
+ public static final String ORDERED_LIBS = "javax.servlet.context.orderedLibs";
+
+ public String getContextPath();
+
+ /**
+ * Returns a ServletContext object that corresponds to a
+ * specified URL on the server.
+ *
+ * This method allows servlets to gain access to the context for various + * parts of the server, and as needed obtain {@link RequestDispatcher} + * objects from the context. The given path must be begin with "/", is + * interpreted relative to the server's document root and is matched against + * the context roots of other web applications hosted on this container. + *
+ * In a security conscious environment, the servlet container may return
+ *
+ * This method allows the servlet container to make a resource available to
+ * servlets from any source. Resources can be located on a local or remote
+ * file system, in a database, or in a
+ * The servlet container must implement the URL handlers and
+ *
+ * This method returns
+ * Some containers may allow writing to the URL returned by this method
+ * using the methods of the URL class.
+ *
+ * The resource content is returned directly, so be aware that requesting a
+ *
+ * This method has a different purpose than
+ *
+ * The data in the
+ * Meta-information such as content length and content type that is
+ * available via
+ * The servlet container must implement the URL handlers and
+ *
+ * This method is different from
+ *
+ * The pathname must begin with a "/" and is interpreted as relative to the
+ * current context root. Use
+ * Servlets (and JSP pages also) may be given names via server
+ * administration or via a web application deployment descriptor. A servlet
+ * instance can determine its name using
+ * {@link ServletConfig#getServletName}.
+ *
+ * This method returns
+ * This method was originally defined to retrieve a servlet from
+ * a
+ * In lieu of this method, servlets can share information using
+ * the
+ * This method was originally defined to return an
+ *
+ * This method was originally defined to return an
+ *
+ * This method was originally defined to write an exception's
+ * stack trace and an explanatory error message to the servlet
+ * log file.
+ */
+ @SuppressWarnings("dep-ann")
+ // Spec API does not use @Deprecated
+ public void log(Exception exception, String msg);
+
+ /**
+ * Writes an explanatory message and a stack trace for a given
+ *
+ * The real path returned will be in a form appropriate to the computer and
+ * operating system on which the servlet container is running, including the
+ * proper path separators. This method returns
+ * The form of the returned string is
+ * servername/versionnumber. For example, the JavaServer Web
+ * Development Kit may return the string
+ *
+ * The servlet container may return other optional information after the
+ * primary string in parentheses, for example,
+ *
+ * This method can make available configuration information useful to an
+ * entire "web application". For example, it can provide a webmaster's email
+ * address or the name of a system that holds critical data.
+ *
+ * @param name
+ * a
+ * The attribute is returned as a
+ * If listeners are configured on the
+ * If a null value is passed, the effect is the same as calling
+ *
+ * Attribute names should follow the same convention as package names. The
+ * Java Servlet API specification reserves names matching
+ *
+ * If listeners are configured on the null for a given URL.
+ *
+ * @param uripath
+ * a String specifying the context path of another
+ * web application in the container.
+ * @return the ServletContext object that corresponds to the
+ * named URL, or null if either none exists or the container wishes
+ * to restrict this access.
+ * @see RequestDispatcher
+ */
+ public ServletContext getContext(String uripath);
+
+ /**
+ * Returns the major version of the Java Servlet API that this servlet
+ * container supports. All implementations that comply with Version 3.1 must
+ * have this method return the integer 3.
+ *
+ * @return 3
+ */
+ public int getMajorVersion();
+
+ /**
+ * Returns the minor version of the Servlet API that this servlet container
+ * supports. All implementations that comply with Version 3.1 must have this
+ * method return the integer 1.
+ *
+ * @return 1
+ */
+ public int getMinorVersion();
+
+ /**
+ * @return TODO
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ *
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public int getEffectiveMajorVersion();
+
+ /**
+ * @return TODO
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public int getEffectiveMinorVersion();
+
+ /**
+ * Returns the MIME type of the specified file, or null if the
+ * MIME type is not known. The MIME type is determined by the configuration
+ * of the servlet container, and may be specified in a web application
+ * deployment descriptor. Common MIME types are "text/html" and
+ * "image/gif".
+ *
+ * @param file
+ * a String specifying the name of a file
+ * @return a String specifying the file's MIME type
+ */
+ public String getMimeType(String file);
+
+ /**
+ * Returns a directory-like listing of all the paths to resources within the
+ * web application whose longest sub-path matches the supplied path
+ * argument. Paths indicating subdirectory paths end with a '/'. The
+ * returned paths are all relative to the root of the web application and
+ * have a leading '/'. For example, for a web application containing
+ *
+ * /welcome.html
+ * /catalog/index.html
+ * /catalog/products.html
+ * /catalog/offers/books.html
+ * /catalog/offers/music.html
+ * /customer/login.jsp
+ * /WEB-INF/web.xml
+ * /WEB-INF/classes/com.acme.OrderServlet.class,
+ *
+ * getResourcePaths("/") returns {"/welcome.html", "/catalog/",
+ * "/customer/", "/WEB-INF/"}
+ * getResourcePaths("/catalog/") returns {"/catalog/index.html",
+ * "/catalog/products.html", "/catalog/offers/"}.
+ *
+ * @param path
+ * the partial path used to match the resources, which must start
+ * with a /
+ * @return a Set containing the directory listing, or null if there are no
+ * resources in the web application whose path begins with the
+ * supplied path.
+ * @since Servlet 2.3
+ */
+ public Set.war file.
+ * URLConnection objects that are necessary to access the
+ * resource.
+ * null if no resource is mapped to the
+ * pathname.
+ * .jsp page returns the JSP source code. Use a
+ * RequestDispatcher instead to include results of an
+ * execution.
+ * java.lang.Class.getResource, which looks up resources based
+ * on a class loader. This method does not use class loaders.
+ *
+ * @param path
+ * a String specifying the path to the resource
+ * @return the resource located at the named path, or null if
+ * there is no resource at that path
+ * @exception MalformedURLException
+ * if the pathname is not given in the correct form
+ */
+ public URL getResource(String path) throws MalformedURLException;
+
+ /**
+ * Returns the resource located at the named path as an
+ * InputStream object.
+ * InputStream can be of any type or length.
+ * The path must be specified according to the rules given in
+ * getResource. This method returns null if no
+ * resource exists at the specified path.
+ * getResource method is lost when using this
+ * method.
+ * URLConnection objects necessary to access the resource.
+ * java.lang.Class.getResourceAsStream, which uses a class
+ * loader. This method allows servlet containers to make a resource
+ * available to a servlet from any location, without using a class loader.
+ *
+ * @param path
+ * a String specifying the path to the resource
+ * @return the InputStream returned to the servlet, or
+ * null if no resource exists at the specified path
+ */
+ public InputStream getResourceAsStream(String path);
+
+ /**
+ * Returns a {@link RequestDispatcher} object that acts as a wrapper for the
+ * resource located at the given path. A RequestDispatcher
+ * object can be used to forward a request to the resource or to include the
+ * resource in a response. The resource can be dynamic or static.
+ * getContext to obtain a
+ * RequestDispatcher for resources in foreign contexts. This
+ * method returns null if the ServletContext
+ * cannot return a RequestDispatcher.
+ *
+ * @param path
+ * a String specifying the pathname to the resource
+ * @return a RequestDispatcher object that acts as a wrapper for
+ * the resource at the specified path, or null if the
+ * ServletContext cannot return a
+ * RequestDispatcher
+ * @see RequestDispatcher
+ * @see ServletContext#getContext
+ */
+ public RequestDispatcher getRequestDispatcher(String path);
+
+ /**
+ * Returns a {@link RequestDispatcher} object that acts as a wrapper for the
+ * named servlet.
+ * null if the ServletContext
+ * cannot return a RequestDispatcher for any reason.
+ *
+ * @param name
+ * a String specifying the name of a servlet to wrap
+ * @return a RequestDispatcher object that acts as a wrapper for
+ * the named servlet, or null if the
+ * ServletContext cannot return a
+ * RequestDispatcher
+ * @see RequestDispatcher
+ * @see ServletContext#getContext
+ * @see ServletConfig#getServletName
+ */
+ public RequestDispatcher getNamedDispatcher(String name);
+
+ /**
+ * @deprecated As of Java Servlet API 2.1, with no direct replacement.
+ * ServletContext. In this version, this method
+ * always returns null and remains only to preserve
+ * binary compatibility. This method will be permanently removed
+ * in a future version of the Java Servlet API.
+ * ServletContext class and can perform shared
+ * business logic by invoking methods on common non-servlet
+ * classes.
+ */
+ @SuppressWarnings("dep-ann")
+ // Spec API does not use @Deprecated
+ public Servlet getServlet(String name) throws ServletException;
+
+ /**
+ * @deprecated As of Java Servlet API 2.0, with no replacement.
+ * Enumeration of all the servlets known to this
+ * servlet context. In this version, this method always returns
+ * an empty enumeration and remains only to preserve binary
+ * compatibility. This method will be permanently removed in a
+ * future version of the Java Servlet API.
+ */
+ @SuppressWarnings("dep-ann")
+ // Spec API does not use @Deprecated
+ public EnumerationEnumeration of all the servlet names known to
+ * this context. In this version, this method always returns an
+ * empty Enumeration and remains only to preserve
+ * binary compatibility. This method will be permanently removed
+ * in a future version of the Java Servlet API.
+ */
+ @SuppressWarnings("dep-ann")
+ // Spec API does not use @Deprecated
+ public EnumerationString specifying the message to be written to
+ * the log file
+ */
+ public void log(String msg);
+
+ /**
+ * @deprecated As of Java Servlet API 2.1, use
+ * {@link #log(String message, Throwable throwable)} instead.
+ * Throwable exception to the servlet log file. The name and
+ * type of the servlet log file is specific to the servlet container,
+ * usually an event log.
+ *
+ * @param message
+ * a String that describes the error or exception
+ * @param throwable
+ * the Throwable error or exception
+ */
+ public void log(String message, Throwable throwable);
+
+ /**
+ * Returns a String containing the real path for a given
+ * virtual path. For example, the path "/index.html" returns the absolute
+ * file path on the server's filesystem would be served by a request for
+ * "http://host/contextPath/index.html", where contextPath is the context
+ * path of this ServletContext..
+ * null if the
+ * servlet container cannot translate the virtual path to a real path for
+ * any reason (such as when the content is being made available from a
+ * .war archive).
+ *
+ * @param path
+ * a String specifying a virtual path
+ * @return a String specifying the real path, or null if the
+ * translation cannot be performed
+ */
+ public String getRealPath(String path);
+
+ /**
+ * Returns the name and version of the servlet container on which the
+ * servlet is running.
+ * JavaServer Web Dev Kit/1.0.
+ * JavaServer Web Dev Kit/1.0 (JDK 1.1.6; Windows NT 4.0 x86).
+ *
+ * @return a String containing at least the servlet container
+ * name and version number
+ */
+ public String getServerInfo();
+
+ /**
+ * Returns a String containing the value of the named
+ * context-wide initialization parameter, or null if the
+ * parameter does not exist.
+ * String containing the name of the parameter
+ * whose value is requested
+ * @return a String containing the value of the initialization
+ * parameter
+ * @see ServletConfig#getInitParameter
+ */
+ public String getInitParameter(String name);
+
+ /**
+ * Returns the names of the context's initialization parameters as an
+ * Enumeration of String objects, or an empty
+ * Enumeration if the context has no initialization parameters.
+ *
+ * @return an Enumeration of String objects
+ * containing the names of the context's initialization parameters
+ * @see ServletConfig#getInitParameter
+ */
+
+ public Enumerationnull if there is no attribute by that name. An attribute
+ * allows a servlet container to give the servlet additional information not
+ * already provided by this interface. See your server documentation for
+ * information about its attributes. A list of supported attributes can be
+ * retrieved using getAttributeNames.
+ * java.lang.Object or some
+ * subclass. Attribute names should follow the same convention as package
+ * names. The Java Servlet API specification reserves names matching
+ * java.*, javax.*, and sun.*.
+ *
+ * @param name
+ * a String specifying the name of the attribute
+ * @return an Object containing the value of the attribute, or
+ * null if no attribute exists matching the given name
+ * @see ServletContext#getAttributeNames
+ */
+ public Object getAttribute(String name);
+
+ /**
+ * Returns an Enumeration containing the attribute names
+ * available within this servlet context. Use the {@link #getAttribute}
+ * method with an attribute name to get the value of an attribute.
+ *
+ * @return an Enumeration of attribute names
+ * @see #getAttribute
+ */
+ public EnumerationServletContext the
+ * container notifies them accordingly.
+ * removeAttribute().
+ * java.*, javax.*, and sun.*.
+ *
+ * @param name
+ * a String specifying the name of the attribute
+ * @param object
+ * an Object representing the attribute to be bound
+ */
+ public void setAttribute(String name, Object object);
+
+ /**
+ * Removes the attribute with the given name from the servlet context. After
+ * removal, subsequent calls to {@link #getAttribute} to retrieve the
+ * attribute's value will return null.
+ * ServletContext the
+ * container notifies them accordingly.
+ *
+ * @param name
+ * a String specifying the name of the attribute to
+ * be removed
+ */
+ public void removeAttribute(String name);
+
+ /**
+ * Returns the name of this web application corresponding to this
+ * ServletContext as specified in the deployment descriptor for this web
+ * application by the display-name element.
+ *
+ * @return The name of the web application or null if no name has been
+ * declared in the deployment descriptor.
+ * @since Servlet 2.3
+ */
+ public String getServletContextName();
+
+ /**
+ * @param servletName
+ * @param className
+ * @return TODO
+ * @throws IllegalStateException
+ * If the context has already been initialised
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public ServletRegistration.Dynamic addServlet(String servletName,
+ String className);
+
+ /**
+ * @param servletName
+ * @param servlet
+ * @return TODO
+ * @throws IllegalStateException
+ * If the context has already been initialised
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public ServletRegistration.Dynamic addServlet(String servletName,
+ Servlet servlet);
+
+ /**
+ * @param servletName
+ * @param servletClass
+ * @return TODO
+ * @throws IllegalStateException
+ * If the context has already been initialised
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public ServletRegistration.Dynamic addServlet(String servletName,
+ Class servletClass);
+
+ /**
+ * @param c
+ * @return TODO
+ * @throws ServletException
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public null if no Servlet has been registered with the
+ * given name
+ *
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ *
+ * @since Servlet 3.0
+ */
+ public ServletRegistration getServletRegistration(String servletName);
+
+ /**
+ * @return TODO
+ * @throws UnsupportedOperationException If called from a
+ * {@link ServletContextListener#contextInitialized(ServletContextEvent)}
+ * method of a {@link ServletContextListener} that was not defined in a
+ * web.xml file, a web-fragment.xml file nor annotated with
+ * {@link javax.servlet.annotation.WebListener}. For example, a
+ * {@link ServletContextListener} defined in a TLD would not be able to
+ * use this method.
+ * @since Servlet 3.0 TODO SERVLET3 - Add comments
+ */
+ public Map