VaadinServlet (Vaadin Platform (vaadin-platform-javadoc) 22.2.2 API)

java.lang.Object
- javax.servlet.GenericServlet
- - javax.servlet.http.HttpServlet
  - - com.vaadin.flow.server.VaadinServlet

All Implemented Interfaces:

Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig
```
public class VaadinServlet
extends javax.servlet.http.HttpServlet
```
The main servlet, which handles all incoming requests to the application.
This servlet is typically subclassed in all applications to provide servlet mappings and init parameters. Together with a web.xml file, it is also possible to use this class directly.
Internally sets up a VaadinService through createServletService(DeploymentConfiguration) and delegates handling of most requests to that.

Since:

1.0

Author:

Vaadin Ltd

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description

VaadinServlet()

Constructors
Constructor and Description
`VaadinServlet()`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected DeploymentConfiguration`	`createDeploymentConfiguration()` Creates a deployment configuration to be used for the creation of a `VaadinService`.
`protected DeploymentConfiguration`	`createDeploymentConfiguration(Properties initParameters)` Creates a deployment configuration to be used for the creation of a `VaadinService`.
`protected VaadinServletService`	`createServletService()` Creates a vaadin servlet service.
`protected VaadinServletService`	`createServletService(DeploymentConfiguration deploymentConfiguration)` Creates a vaadin servlet service.
`protected StaticFileHandler`	`createStaticFileHandler(VaadinService vaadinService)` Creates a new instance of `StaticFileHandler`, that is responsible to find and serve static resources.
`protected VaadinServletRequest`	`createVaadinRequest(javax.servlet.http.HttpServletRequest request)` Creates a Vaadin request for a http servlet request.
`void`	`destroy()`
`static VaadinServlet`	`getCurrent()` Gets the currently used Vaadin servlet.
`protected static String`	`getLastPathParameter(String uri)` Finds any path parameter added to the last part of the uri.
`VaadinServletService`	`getService()` Gets the Vaadin service for this servlet.
`javax.servlet.ServletConfig`	`getServletConfig()`
`protected boolean`	`handleContextOrServletRootWithoutSlash(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)` Invoked for every request to this servlet to potentially send a redirect to avoid problems with requests to the context root with no trailing slash.
`void`	`init(javax.servlet.ServletConfig servletConfig)` Called by the servlet container to indicate to a servlet that the servlet is being placed into service.
`protected boolean`	`serveStaticOrWebJarRequest(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)` Handles a request by serving a static file from Webpack when in npm-dev-mode, or from a WebJar when in bower-dev-mode or from the file-system when in production.
`protected void`	`service(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response)` Receives standard HTTP requests from the public service method and dispatches them.
`protected void`	`servletInitialized()`

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

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

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

- Constructor Detail
  - VaadinServlet
```
public VaadinServlet()
```
- Method Detail
  - init
```
public void init(javax.servlet.ServletConfig servletConfig)
          throws javax.servlet.ServletException
```
    Called by the servlet container to indicate to a servlet that the servlet is being placed into service.
    
    Specified by:
    
    init in interface javax.servlet.Servlet
    
    Overrides:
    
    init in class javax.servlet.GenericServlet
    
    Parameters:
    
    servletConfig - the object containing the servlet's configuration and initialization parameters
    
    Throws:
    
    javax.servlet.ServletException - if an exception has occurred that interferes with the servlet's normal operation.
  - getServletConfig
```
public javax.servlet.ServletConfig getServletConfig()
```
    Specified by:
    
    getServletConfig in interface javax.servlet.Servlet
    
    Overrides:
    
    getServletConfig in class javax.servlet.GenericServlet
  - createStaticFileHandler
```
protected StaticFileHandler createStaticFileHandler(VaadinService vaadinService)
```
    Creates a new instance of StaticFileHandler, that is responsible to find and serve static resources. By default it returns a StaticFileServer instance.
    
    Parameters:
    
    vaadinService - the vaadinService created at createServletService()
    
    Returns:
    
    the file server to be used by this servlet, not null
  - servletInitialized
```
protected void servletInitialized()
                           throws javax.servlet.ServletException
```
    Throws:
    
    javax.servlet.ServletException
  - getCurrent
```
public static VaadinServlet getCurrent()
```
    Gets the currently used Vaadin servlet. The current servlet is automatically defined when initializing the servlet and when processing requests to the server (see ThreadLocal) and in VaadinSession.access(Command) and UI.access(Command). In other cases, (e.g. from background threads), the current servlet is not automatically defined.
    The current servlet is derived from the current service using VaadinService.getCurrent()
    
    Returns:
    
    the current Vaadin servlet instance if available, otherwise null
  - createDeploymentConfiguration
```
protected DeploymentConfiguration createDeploymentConfiguration()
                                                         throws javax.servlet.ServletException
```
    Creates a deployment configuration to be used for the creation of a VaadinService. Intended to be used by dependency injection frameworks.
    
    Returns:
    
    the created deployment configuration
    
    Throws:
    
    javax.servlet.ServletException
  - createDeploymentConfiguration
```
protected DeploymentConfiguration createDeploymentConfiguration(Properties initParameters)
```
    Creates a deployment configuration to be used for the creation of a VaadinService. Override this if you want to override certain properties.
    
    Parameters:
    
    initParameters - the context-param and init-param values as properties
    
    Returns:
    
    the created deployment configuration
  - createServletService
```
protected VaadinServletService createServletService()
                                             throws javax.servlet.ServletException,
                                                    ServiceException
```
    Creates a vaadin servlet service. This method functions as a layer of indirection between init(ServletConfig) and createServletService(DeploymentConfiguration) so dependency injection frameworks can call createDeploymentConfiguration() when creating a vaadin servlet service lazily.
    
    Returns:
    
    the created vaadin servlet service
    
    Throws:
    
    javax.servlet.ServletException - if creating a deployment configuration fails
    
    ServiceException - if creating the vaadin servlet service fails
  - createServletService
```
protected VaadinServletService createServletService(DeploymentConfiguration deploymentConfiguration)
                                             throws ServiceException
```
    Creates a vaadin servlet service.
    
    Parameters:
    
    deploymentConfiguration - the deployment configuration to be used
    
    Returns:
    
    the created vaadin servlet service
    
    Throws:
    
    ServiceException - if creating the vaadin servlet service fails
  - service
```
protected void service(javax.servlet.http.HttpServletRequest request,
                       javax.servlet.http.HttpServletResponse response)
                throws javax.servlet.ServletException,
                       IOException
```
    Receives standard HTTP requests from the public service method and dispatches them.
    
    Overrides:
    
    service in class javax.servlet.http.HttpServlet
    
    Parameters:
    
    request - the object that contains the request the client made of the servlet.
    
    response - the object that contains the response the servlet returns to the client.
    
    Throws:
    
    javax.servlet.ServletException - if an input or output error occurs while the servlet is handling the TRACE request.
    
    IOException - if the request for the TRACE cannot be handled.
  - serveStaticOrWebJarRequest
```
protected boolean serveStaticOrWebJarRequest(javax.servlet.http.HttpServletRequest request,
                                             javax.servlet.http.HttpServletResponse response)
                                      throws IOException
```
    Handles a request by serving a static file from Webpack when in npm-dev-mode, or from a WebJar when in bower-dev-mode or from the file-system when in production. It's not done via VaadinService handlers because static requests do not need a established session.
    
    Parameters:
    
    request - the HTTP servlet request object that contains the request the client made of the servlet
    
    response - the HTTP servlet response object that contains the response the servlet returns to the client
    
    Returns:
    
    true if the request was handled a response written; otherwise false
    
    Throws:
    
    IOException - if an input or output error occurs while the servlet is handling the HTTP request
  - handleContextOrServletRootWithoutSlash
```
protected boolean handleContextOrServletRootWithoutSlash(javax.servlet.http.HttpServletRequest request,
                                                         javax.servlet.http.HttpServletResponse response)
                                                  throws IOException
```
    Invoked for every request to this servlet to potentially send a redirect to avoid problems with requests to the context root with no trailing slash.
    
    Parameters:
    
    request - the processed request
    
    response - the processed response
    
    Returns:
    
    true if a redirect has been sent and the request should not be processed further; false if the request should be processed as usual
    
    Throws:
    
    IOException - If an input or output exception occurs
  - getLastPathParameter
```
protected static String getLastPathParameter(String uri)
```
    Finds any path parameter added to the last part of the uri. A path parameter is any string separated by ";" from the path and ends in / or at the end of the string.
    For example the uri http://myhost.com/foo;a=1/bar;b=1 contains two path parameters, a=1 related to /foo and b=1 related to /bar.
    For http://myhost.com/foo;a=1/bar;b=1 this method will return ;b=1
    
    Parameters:
    
    uri - a URI
    
    Returns:
    
    the last path parameter of the uri including the semicolon or an empty string. Never null.
  - createVaadinRequest
```
protected VaadinServletRequest createVaadinRequest(javax.servlet.http.HttpServletRequest request)
```
    Creates a Vaadin request for a http servlet request. This method can be overridden if the Vaadin request should have special properties.
    
    Parameters:
    
    request - the original http servlet request
    
    Returns:
    
    a Vaadin request for the original request
  - getService
```
public VaadinServletService getService()
```
    Gets the Vaadin service for this servlet.
    
    Returns:
    
    the Vaadin service
  - destroy
```
public void destroy()
```
    Specified by:
    
    destroy in interface javax.servlet.Servlet
    
    Overrides:
    
    destroy in class javax.servlet.GenericServlet

Class VaadinServlet

Constructor Summary

Method Summary

Methods inherited from class javax.servlet.http.HttpServlet

Methods inherited from class javax.servlet.GenericServlet

Methods inherited from class java.lang.Object

Constructor Detail

VaadinServlet

Method Detail

init

getServletConfig

createStaticFileHandler

servletInitialized

getCurrent

createDeploymentConfiguration

createDeploymentConfiguration

createServletService

createServletService

service

serveStaticOrWebJarRequest

handleContextOrServletRootWithoutSlash

getLastPathParameter

createVaadinRequest

getService

destroy