org.apache.catalina.core
Class ApplicationContextFacade

java.lang.Object
  org.apache.catalina.core.ApplicationContextFacade

All Implemented Interfaces:

javax.servlet.ServletContext

public final class ApplicationContextFacade
extends java.lang.Object
implements javax.servlet.ServletContext

Facade object which masks the internal ApplicationContext object from the web application.

Author:

Remy Maucherat, Jean-Francois Arcand

ApplicationContextFacade

public ApplicationContextFacade(ApplicationContext context)

Construct a new instance of this class, associated with the specified Context instance.

Parameters:

context - The associated Context instance

getContext

public javax.servlet.ServletContext getContext(java.lang.String uripath)

Description copied from interface: javax.servlet.ServletContext

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 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 null for a given URL.

Specified by:

getContext in interface javax.servlet.ServletContext

Parameters:

uripath - a String specifying the context path of another web application in the container.

Returns:

the ServletContext object that corresponds to the named URL, or null if either none exists or the container wishes to restrict this access.

See Also:

RequestDispatcher

getMajorVersion

public int getMajorVersion()

Description copied from interface: javax.servlet.ServletContext

Returns the major version of the Java Servlet API that this servlet container supports. All implementations that comply with Version 2.4 must have this method return the integer 2.

Specified by:

getMajorVersion in interface javax.servlet.ServletContext

Returns:

2

getMinorVersion

public int getMinorVersion()

Description copied from interface: javax.servlet.ServletContext

Returns the minor version of the Servlet API that this servlet container supports. All implementations that comply with Version 2.5 must have this method return the integer 5.

Specified by:

getMinorVersion in interface javax.servlet.ServletContext

Returns:

5

getMimeType

public java.lang.String getMimeType(java.lang.String file)

Description copied from interface: javax.servlet.ServletContext

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".

Specified by:

getMimeType in interface javax.servlet.ServletContext

Parameters:

file - a String specifying the name of a file

Returns:

a String specifying the file's MIME type

getResourcePaths

public java.util.Set getResourcePaths(java.lang.String path)

Description copied from interface: javax.servlet.ServletContext

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/"}.

Specified by:

getResourcePaths in interface javax.servlet.ServletContext

Parameters:

path - the partial path used to match the resources, which must start with a /

Returns:

a Set containing the directory listing, or null if there are no resources in the web application whose path begins with the supplied path.

getResource

public java.net.URL getResource(java.lang.String path)
                         throws java.net.MalformedURLException

Description copied from interface: javax.servlet.ServletContext

Returns a URL to the resource that is mapped to a specified path. The path must begin with a "/" and is interpreted as relative to the current context root.

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 .war file.

The servlet container must implement the URL handlers and URLConnection objects that are necessary to access the resource.

This method returns null if no resource is mapped to the pathname.

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 .jsp page returns the JSP source code. Use a RequestDispatcher instead to include results of an execution.

This method has a different purpose than java.lang.Class.getResource, which looks up resources based on a class loader. This method does not use class loaders.

Specified by:

getResource in interface javax.servlet.ServletContext

Parameters:

path - a String specifying the path to the resource

Returns:

the resource located at the named path, or null if there is no resource at that path

Throws:

java.net.MalformedURLException - if the pathname is not given in the correct form

getResourceAsStream

public java.io.InputStream getResourceAsStream(java.lang.String path)

Description copied from interface: javax.servlet.ServletContext

Returns the resource located at the named path as an InputStream object.

The data in the 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.

Meta-information such as content length and content type that is available via getResource method is lost when using this method.

The servlet container must implement the URL handlers and URLConnection objects necessary to access the resource.

This method is different from 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.

Specified by:

getResourceAsStream in interface javax.servlet.ServletContext

Parameters:

path - a String specifying the path to the resource

Returns:

the InputStream returned to the servlet, or null if no resource exists at the specified path

getRequestDispatcher

public javax.servlet.RequestDispatcher getRequestDispatcher(java.lang.String path)

Description copied from interface: javax.servlet.ServletContext

Returns a 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.

The pathname must begin with a "/" and is interpreted as relative to the current context root. Use getContext to obtain a RequestDispatcher for resources in foreign contexts. This method returns null if the ServletContext cannot return a RequestDispatcher.

Specified by:

getRequestDispatcher in interface javax.servlet.ServletContext

Parameters:

path - a String specifying the pathname to the resource

Returns:

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 Also:

RequestDispatcher, ServletContext.getContext(java.lang.String)

getNamedDispatcher

public javax.servlet.RequestDispatcher getNamedDispatcher(java.lang.String name)

Description copied from interface: javax.servlet.ServletContext

Returns a RequestDispatcher object that acts as a wrapper for the named servlet.

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 ServletConfig.getServletName().

This method returns null if the ServletContext cannot return a RequestDispatcher for any reason.

Specified by:

getNamedDispatcher in interface javax.servlet.ServletContext

Parameters:

name - a String specifying the name of a servlet to wrap

Returns:

a RequestDispatcher object that acts as a wrapper for the named servlet, or null if the ServletContext cannot return a RequestDispatcher

See Also:

RequestDispatcher, ServletContext.getContext(java.lang.String), ServletConfig.getServletName()

getServlet

public javax.servlet.Servlet getServlet(java.lang.String name)
                                 throws javax.servlet.ServletException

Specified by:

getServlet in interface javax.servlet.ServletContext

Throws:

javax.servlet.ServletException

getServlets

public java.util.Enumeration getServlets()

Specified by:

getServlets in interface javax.servlet.ServletContext

getServletNames

public java.util.Enumeration getServletNames()

Specified by:

getServletNames in interface javax.servlet.ServletContext

log

public void log(java.lang.String msg)

Description copied from interface: javax.servlet.ServletContext

Writes the specified message to a servlet log file, usually an event log. The name and type of the servlet log file is specific to the servlet container.

Specified by:

log in interface javax.servlet.ServletContext

Parameters:

msg - a String specifying the message to be written to the log file

log

public void log(java.lang.Exception exception,
                java.lang.String msg)

Specified by:

log in interface javax.servlet.ServletContext

log

public void log(java.lang.String message,
                java.lang.Throwable throwable)

Description copied from interface: javax.servlet.ServletContext

Writes an explanatory message and a stack trace for a given 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.

Specified by:

log in interface javax.servlet.ServletContext

Parameters:

message - a String that describes the error or exception

throwable - the Throwable error or exception

getRealPath

public java.lang.String getRealPath(java.lang.String path)

Description copied from interface: javax.servlet.ServletContext

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..

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 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).

Specified by:

getRealPath in interface javax.servlet.ServletContext

Parameters:

path - a String specifying a virtual path

Returns:

a String specifying the real path, or null if the translation cannot be performed

getServerInfo

public java.lang.String getServerInfo()

Description copied from interface: javax.servlet.ServletContext

Returns the name and version of the servlet container on which the servlet is running.

The form of the returned string is servername/versionnumber. For example, the JavaServer Web Development Kit may return the string JavaServer Web Dev Kit/1.0.

The servlet container may return other optional information after the primary string in parentheses, for example, JavaServer Web Dev Kit/1.0 (JDK 1.1.6; Windows NT 4.0 x86).

Specified by:

getServerInfo in interface javax.servlet.ServletContext

Returns:

a String containing at least the servlet container name and version number

getInitParameter

public java.lang.String getInitParameter(java.lang.String name)

Description copied from interface: javax.servlet.ServletContext

Returns a String containing the value of the named context-wide initialization parameter, or null if the parameter does not exist.

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.

Specified by:

getInitParameter in interface javax.servlet.ServletContext

Parameters:

name - a String containing the name of the parameter whose value is requested

Returns:

a String containing the value of the initialization parameter

See Also:

ServletConfig.getInitParameter(java.lang.String)

getInitParameterNames

public java.util.Enumeration getInitParameterNames()

Description copied from interface: javax.servlet.ServletContext

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.

Specified by:

getInitParameterNames in interface javax.servlet.ServletContext

Returns:

an Enumeration of String objects containing the names of the context's initialization parameters

See Also:

ServletConfig.getInitParameter(java.lang.String)

getAttribute

public java.lang.Object getAttribute(java.lang.String name)

Description copied from interface: javax.servlet.ServletContext

Returns the servlet container attribute with the given name, or null 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.

The attribute is returned as a 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.*.

Specified by:

getAttribute in interface javax.servlet.ServletContext

Parameters:

name - a String specifying the name of the attribute

Returns:

an Object containing the value of the attribute, or null if no attribute exists matching the given name

See Also:

ServletContext.getAttributeNames()

getAttributeNames

public java.util.Enumeration getAttributeNames()

Description copied from interface: javax.servlet.ServletContext

Returns an Enumeration containing the attribute names available within this servlet context. Use the ServletContext.getAttribute(java.lang.String) method with an attribute name to get the value of an attribute.

Specified by:

getAttributeNames in interface javax.servlet.ServletContext

Returns:

an Enumeration of attribute names

See Also:

ServletContext.getAttribute(java.lang.String)

setAttribute

public void setAttribute(java.lang.String name,
                         java.lang.Object object)

Description copied from interface: javax.servlet.ServletContext

Binds an object to a given attribute name in this servlet context. If the name specified is already used for an attribute, this method will replace the attribute with the new to the new attribute.

If listeners are configured on the ServletContext the container notifies them accordingly.

If a null value is passed, the effect is the same as calling removeAttribute().

Attribute names should follow the same convention as package names. The Java Servlet API specification reserves names matching java.*, javax.*, and sun.*.

Specified by:

setAttribute in interface javax.servlet.ServletContext

Parameters:

name - a String specifying the name of the attribute

object - an Object representing the attribute to be bound

removeAttribute

public void removeAttribute(java.lang.String name)

Description copied from interface: javax.servlet.ServletContext

Removes the attribute with the given name from the servlet context. After removal, subsequent calls to ServletContext.getAttribute(java.lang.String) to retrieve the attribute's value will return null.

If listeners are configured on the ServletContext the container notifies them accordingly.

Specified by:

removeAttribute in interface javax.servlet.ServletContext

Parameters:

name - a String specifying the name of the attribute to be removed

getServletContextName

public java.lang.String getServletContextName()

Description copied from interface: javax.servlet.ServletContext

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.

Specified by:

getServletContextName in interface javax.servlet.ServletContext

Returns:

The name of the web application or null if no name has been declared in the deployment descriptor.

getContextPath

public java.lang.String getContextPath()

Specified by:

getContextPath in interface javax.servlet.ServletContext