类 OncePerRequestFilter

字段详细资料

• ALREADY_FILTERED_SUFFIX

  public static final String ALREADY_FILTERED_SUFFIX

  Suffix that gets appended to the filter name for the "already filtered" request attribute.

  另请参阅:

  getAlreadyFilteredAttributeName(), 常量字段值

构造器详细资料

• OncePerRequestFilter

  public OncePerRequestFilter()

方法详细资料

• doFilter

  public final void doFilter​(ServletRequest request,
                             ServletResponse response,
                             FilterChain filterChain)
                      throws ServletException,
                             IOException

  This doFilter implementation stores a request attribute for "already filtered", proceeding without filtering again if the attribute is already there.

  抛出:

  ServletException

  IOException

  另请参阅:

  getAlreadyFilteredAttributeName(), shouldNotFilter(javax.servlet.http.HttpServletRequest), doFilterInternal(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, javax.servlet.FilterChain)

• isAsyncDispatch

  protected boolean isAsyncDispatch​(HttpServletRequest request)

  The dispatcher type javax.servlet.DispatcherType.ASYNC introduced in Servlet 3.0 means a filter can be invoked in more than one thread over the course of a single request. This method returns true if the filter is currently executing within an asynchronous dispatch.

  参数:

  request - the current request

  从以下版本开始:

  3.2

  另请参阅:

  WebAsyncManager.hasConcurrentResult()

• isAsyncStarted

  protected boolean isAsyncStarted​(HttpServletRequest request)

  Whether request processing is in asynchronous mode meaning that the response will not be committed after the current thread is exited.

  参数:

  request - the current request

  从以下版本开始:

  3.2

  另请参阅:

  WebAsyncManager.isConcurrentHandlingStarted()

• getAlreadyFilteredAttributeName

  protected String getAlreadyFilteredAttributeName()

  Return the name of the request attribute that identifies that a request is already filtered.

  The default implementation takes the configured name of the concrete filter instance and appends ".FILTERED". If the filter is not fully initialized, it falls back to its class name.

  另请参阅:

  GenericFilterBean.getFilterName(), ALREADY_FILTERED_SUFFIX

• shouldNotFilter

  protected boolean shouldNotFilter​(HttpServletRequest request)
                             throws ServletException

  Can be overridden in subclasses for custom filtering control, returning true to avoid filtering of the given request.

  The default implementation always returns false.

  参数:

  request - current HTTP request

  返回:

  whether the given request should not be filtered

  抛出:

  ServletException - in case of errors

• shouldNotFilterAsyncDispatch

  protected boolean shouldNotFilterAsyncDispatch()

  The dispatcher type javax.servlet.DispatcherType.ASYNC introduced in Servlet 3.0 means a filter can be invoked in more than one thread over the course of a single request. Some filters only need to filter the initial thread (e.g. request wrapping) while others may need to be invoked at least once in each additional thread for example for setting up thread locals or to perform final processing at the very end.

  Note that although a filter can be mapped to handle specific dispatcher types via web.xml or in Java through the ServletContext, servlet containers may enforce different defaults with regards to dispatcher types. This flag enforces the design intent of the filter.

  The default return value is "true", which means the filter will not be invoked during subsequent async dispatches. If "false", the filter will be invoked during async dispatches with the same guarantees of being invoked only once during a request within a single thread.

  从以下版本开始:

  3.2

• shouldNotFilterErrorDispatch

  protected boolean shouldNotFilterErrorDispatch()

  Whether to filter error dispatches such as when the servlet container processes and error mapped in web.xml. The default return value is "true", which means the filter will not be invoked in case of an error dispatch.

  从以下版本开始:

  3.2

• doFilterInternal

  protected abstract void doFilterInternal​(HttpServletRequest request,
                                           HttpServletResponse response,
                                           FilterChain filterChain)
                                    throws ServletException,
                                           IOException

  Same contract as for doFilter, but guaranteed to be just invoked once per request within a single request thread. See shouldNotFilterAsyncDispatch() for details.

  Provides HttpServletRequest and HttpServletResponse arguments instead of the default ServletRequest and ServletResponse ones.

  抛出:

  ServletException

  IOException