Servlet (Sans Pareil Technologies, Inc.

java.lang.Object
- javax.servlet.GenericServlet
- - javax.servlet.http.HttpServlet
  - - nextapp.echo.webcontainer.WebContainerServlet
    - - com.sptci.echo.http.Servlet

All Implemented Interfaces:

Serializable, Servlet, ServletConfig
```
public class Servlet
extends WebContainerServlet
```
Generic Echo3 Servlet Implementation. The following init-param parameters must be configured for the servlet.
1. applicationInstance - The fully qualified name of the ApplicationInstance class to initialise in newApplicationInstance().
2. contentPane - The fully qualified name of the ContentPane class to use in Application.init().
3. styleSheet - The fully qualified name of the StyleSheet class to use in Application.init().
In addition the followin optional parameters may be configured:
1. dataDirectory - The name of the system property used to specify the root directory under which the application stores persistent state information.
Copyright 2006 Sans Pareil Technologies, Inc.
Version:

$Id: Servlet.java 4951 2010-03-10 20:33:37Z rakesh $

Author:

Rakesh Vidyadharan 2006-11-23

See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from class nextapp.echo.webcontainer.WebContainerServlet
  WebContainerServlet.MultipartRequestWrapper

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`APPLICATION_INSTANCE` The name of the `init-param` used to configure the name of the `ApplicationInstance` that is to be returned by this servlet.
`protected String`	`className` The fully qualified name of the `ApplicationInstance` class that will be returned by `newApplicationInstance()`.
`static String`	`CONTENT_PANE` The name of the `init-param` used to configure the name of the `ContentPane` that is to be set for `Application.window` in `Application.init()`.
`protected String`	`contentPane` The fully qualified name of the `ContentPane` class that will be used in `Application.init()`.
`protected Map<String,String>`	`contextParameters` The map of all the context parameters specified for the web app.
`static String`	`DATA_DIRECTORY` The name of the `init-param` used to specify the name of the `System Property` that must be set for the JVM that indicates the location of the root persistent state directory.
`protected String`	`dataDirectory` The name of the system property used to specify the root directory to use to store persistent state information.
`protected static Logger`	`logger` The logger used to log errors to.
`protected ThreadLocal<Principal>`	`principal` A `ThreadLocal` field used to store the `Principal` object that represents the name of the current authenticated user.
`static String`	`STYLE_SHEET` The name of the `init-param` used to configure the name of the `StyleSheet` that is to be set for `Application` in `Application.init()`.
`protected MutableStyleSheet`	`styleSheet` The global instance of the style sheet for the application used in `Application.init()`.
`protected ThreadLocal<User>`	`user` A `ThreadLocal` field used to store the `User` object that represents the currently logged in user.

Fields inherited from class nextapp.echo.webcontainer.WebContainerServlet
DEBUG_PRINT_MESSAGES_TO_CONSOLE, DISABLE_CACHING, ENABLE_CLIENT_DEBUG_CONSOLE, INSTANCE_MODE_SINGLE, INSTANCE_MODE_WINDOW, SERVICE_ID_BLANK_DOCUMENT, SERVICE_ID_DEFAULT, SERVICE_ID_NEW_INSTANCE, SERVICE_ID_PARAMETER, SERVICE_ID_SESSION_EXPIRED, USER_INSTANCE_ID_PARAMETER

Constructor Summary

Constructors
Constructor and Description

Servlet()
Default constructor.

Constructors
Constructor and Description
`Servlet()` Default constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`String`	`getBookmarkIcon()`
`void`	`init()` Over-ridden to load the application property file and set the necessary properties.
`ApplicationInstance`	`newApplicationInstance()` Implementation of mandatory method in `WebContainerServlet`.
`protected void`	`populateContextParameters()` Populate `contextParameters` with the information in web.xml.
`protected void`	`process(HttpServletRequest request, HttpServletResponse response)` Over-ridden to handle all uncaught exceptions.
`protected void`	`processBackground()` Set the background system property if specified in web.xml
`protected void`	`processLogo()` Configure the application logo is specified in web.xml
`protected String`	`processParameter(String name)` Search for the specified parameter in the servlet config or servlet context and if available set a system property with the name-value pair.

Methods inherited from class nextapp.echo.webcontainer.WebContainerServlet
addInitScript, addInitStyleSheet, doGet, doPost, getActiveConnection, getInitScripts, getInitStyleSheets, getInstanceMode, getMultipartRequestWrapper, getResourceRegistry, getServiceRegistry, setMultipartRequestWrapper

Methods inherited from class javax.servlet.http.HttpServlet
doDelete, doHead, doOptions, doPut, doTrace, getLastModified, service, service

Methods inherited from class javax.servlet.GenericServlet
destroy, getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - logger
```
protected static final Logger logger
```
    The logger used to log errors to.
  - APPLICATION_INSTANCE
```
public static final String APPLICATION_INSTANCE
```
    The name of the init-param used to configure the name of the ApplicationInstance that is to be returned by this servlet. "applicationInstance"
    
    See Also:
    
    Constant Field Values
  - CONTENT_PANE
```
public static final String CONTENT_PANE
```
    The name of the init-param used to configure the name of the ContentPane that is to be set for Application.window in Application.init(). "contentPane"
    
    See Also:
    
    Constant Field Values
  - STYLE_SHEET
```
public static final String STYLE_SHEET
```
    The name of the init-param used to configure the name of the StyleSheet that is to be set for Application in Application.init(). "styleSheet"
    
    See Also:
    
    Constant Field Values
  - DATA_DIRECTORY
```
public static final String DATA_DIRECTORY
```
    The name of the init-param used to specify the name of the System Property that must be set for the JVM that indicates the location of the root persistent state directory. "dataDirectory"
    
    See Also:
    
    Constant Field Values
  - className
```
protected String className
```
    The fully qualified name of the ApplicationInstance class that will be returned by newApplicationInstance().
  - contentPane
```
protected String contentPane
```
    The fully qualified name of the ContentPane class that will be used in Application.init().
  - styleSheet
```
protected MutableStyleSheet styleSheet
```
    The global instance of the style sheet for the application used in Application.init().
  - dataDirectory
```
protected String dataDirectory
```
    The name of the system property used to specify the root directory to use to store persistent state information.
  - contextParameters
```
protected final Map<String,String> contextParameters
```
    The map of all the context parameters specified for the web app.
  - user
```
protected transient ThreadLocal<User> user
```
    A ThreadLocal field used to store the User object that represents the currently logged in user. This is populated only for applications that require authentication and/or authorisation.
  - principal
```
protected transient ThreadLocal<Principal> principal
```
    A ThreadLocal field used to store the Principal object that represents the name of the current authenticated user. This applies usually to container managed authentication as opposed to user that applies to application managed authentication.
- Constructor Detail
  - Servlet
```
public Servlet()
```
    Default constructor. Set the system property for headless operation, in case we need access to the graphics context.
- Method Detail
  - newApplicationInstance
```
public ApplicationInstance newApplicationInstance()
```
    Implementation of mandatory method in WebContainerServlet.
    
    Specified by:
    
    newApplicationInstance in class WebContainerServlet
    
    Returns:
    
    Returns a new instance of the configured application instance.
  - getBookmarkIcon
```
public String getBookmarkIcon()
```
    Overrides:
    
    getBookmarkIcon in class WebContainerServlet
    
    Returns:
    
    Over-ridden to return favicon.ico.
  - init
```
public void init()
          throws ServletException
```
    Over-ridden to load the application property file and set the necessary properties.
    
    Overrides:
    
    init in class GenericServlet
    
    Throws:
    
    ServletException - If errors are encountered while initialising the styleSheet.
  - populateContextParameters
```
protected void populateContextParameters()
```
    Populate contextParameters with the information in web.xml.
  - processBackground
```
protected void processBackground()
```
    Set the background system property if specified in web.xml
  - processLogo
```
protected void processLogo()
```
    Configure the application logo is specified in web.xml
  - processParameter
```
protected String processParameter(String name)
```
    Search for the specified parameter in the servlet config or servlet context and if available set a system property with the name-value pair.
    
    Parameters:
    
    name - The name of the parameter to search for.
    
    Returns:
    
    The value of the parameter if found.
  - process
```
protected void process(HttpServletRequest request,
                       HttpServletResponse response)
                throws IOException,
                       ServletException
```
    Over-ridden to handle all uncaught exceptions. The default action is to log the full stack trace for the error condition.
    
    Overrides:
    
    process in class WebContainerServlet
    
    Throws:
    
    IOException
    
    ServletException

Class Servlet

Nested Class Summary

Nested classes/interfaces inherited from class nextapp.echo.webcontainer.WebContainerServlet

Field Summary

Fields inherited from class nextapp.echo.webcontainer.WebContainerServlet

Constructor Summary

Method Summary

Methods inherited from class nextapp.echo.webcontainer.WebContainerServlet

Methods inherited from class javax.servlet.http.HttpServlet

Methods inherited from class javax.servlet.GenericServlet

Methods inherited from class java.lang.Object

Field Detail

logger

APPLICATION_INSTANCE

CONTENT_PANE

STYLE_SHEET

DATA_DIRECTORY

className

contentPane

styleSheet

dataDirectory

contextParameters

user

principal

Constructor Detail

Servlet

Method Detail

newApplicationInstance

getBookmarkIcon

init

populateContextParameters

processBackground

processLogo

processParameter

process