程序包 cn.taketoday.web.servlet

类 ServletUtils

java.lang.Object
cn.taketoday.web.servlet.ServletUtils
public abstract class ServletUtils extends Object
从以下版本开始:
3.0
作者:
TODAY 2020/12/8 23:07

  • 字段详细资料

    • SESSION_MUTEX_ATTRIBUTE

      public static final String SESSION_MUTEX_ATTRIBUTE
      Key for the mutex session attribute.

    • WEB_APPLICATION_CONTEXT_ATTRIBUTE

      public static final String WEB_APPLICATION_CONTEXT_ATTRIBUTE
      Request attribute to hold the current web application context. Otherwise only the global web app context is obtainable by tags etc.

    • SUBMIT_IMAGE_SUFFIXES

      public static final String[] SUBMIT_IMAGE_SUFFIXES
      Name suffixes in case of image buttons. @since 4.0

    • TEMP_DIR_CONTEXT_ATTRIBUTE

      public static final String TEMP_DIR_CONTEXT_ATTRIBUTE
      Standard Servlet spec context attribute that specifies a temporary directory for the current web application, of type java.io.File.
      从以下版本开始:
      4.0
      另请参阅:

    • HTML_ESCAPE_CONTEXT_PARAM

      public static final String HTML_ESCAPE_CONTEXT_PARAM
      HTML escape parameter at the servlet context level (i.e. a context-param in web.xml): "defaultHtmlEscape".
      从以下版本开始:
      4.0
      另请参阅:

    • RESPONSE_ENCODED_HTML_ESCAPE_CONTEXT_PARAM

      public static final String RESPONSE_ENCODED_HTML_ESCAPE_CONTEXT_PARAM
      Use of response encoding for HTML escaping parameter at the servlet context level (i.e. a context-param in web.xml): "responseEncodedHtmlEscape".
      从以下版本开始:
      4.0
      另请参阅:

    • WEB_APP_ROOT_KEY_PARAM

      public static final String WEB_APP_ROOT_KEY_PARAM
      Web app root key parameter at the servlet context level (i.e. a context-param in web.xml): "webAppRootKey".
      从以下版本开始:
      4.0
      另请参阅:

    • DEFAULT_WEB_APP_ROOT_KEY

      public static final String DEFAULT_WEB_APP_ROOT_KEY
      Default web app root key: "webapp.root".
      从以下版本开始:
      4.0
      另请参阅:

  • 构造器详细资料

    • ServletUtils

      public ServletUtils()

  • 方法详细资料

    • getRequestContext

      public static RequestContext getRequestContext(ServletRequest request, ServletResponse response)

    • getRequestContext

      public static RequestContext getRequestContext(WebApplicationContext webApplicationContext, HttpServletRequest request, HttpServletResponse response)

    • getHttpSession

      public static HttpSession getHttpSession(RequestContext context)
      Get HttpSession
      抛出:
      IllegalStateException - Not run in servlet

    • getHttpSession

      public static HttpSession getHttpSession(RequestContext context, boolean create)
      Returns the current HttpSession associated with this request or, if there is no current session and create is true, returns a new session.

      If create is false and the request has no valid HttpSession, this method returns null.

      To make sure the session is properly maintained, you must call this method before the response is committed. If the container is using cookies to maintain session integrity and is asked to create a new session when the response is committed, an IllegalStateException is thrown.

      参数:
      create - true to create a new session for this request if necessary; false to return null if there's no current session
      返回:
      the HttpSession associated with this request or null if create is false and the request has no valid session
      抛出:
      IllegalStateException - Not run in servlet
      另请参阅:

    • getNativeRequest

      @Nullable public static <T> T getNativeRequest(ServletRequest request, @Nullable Class<T> requiredType)
      Return an appropriate request object of the specified type, if available, unwrapping the given request as far as necessary.
      参数:
      request - the servlet request to introspect
      requiredType - the desired type of request object
      返回:
      the matching request object, or null if none of that type is available

    • getNativeResponse

      @Nullable public static <T> T getNativeResponse(ServletResponse response, @Nullable Class<T> requiredType)
      Return an appropriate response object of the specified type, if available, unwrapping the given response as far as necessary.
      参数:
      response - the servlet response to introspect
      requiredType - the desired type of response object
      返回:
      the matching response object, or null if none of that type is available

    • getServletRequest

      public static HttpServletRequest getServletRequest(RequestContext context)
      Return an appropriate HttpServletRequest object
      参数:
      context - the context to introspect
      返回:
      the matching request object
      另请参阅:

    • getServletContext

      public static ServletContext getServletContext(RequestContext context)
      Gets the servlet context to which this ServletRequest was last dispatched.
      返回:
      the servlet context to which this ServletRequest was last dispatched
      从以下版本开始:
      4.0

    • getServletResponse

      public static HttpServletResponse getServletResponse(RequestContext context)
      Return an appropriate response object
      参数:
      context - the context to introspect
      返回:
      the matching response object
      另请参阅:

    • findWebApplicationContext

      @Nullable public static WebApplicationContext findWebApplicationContext(ServletRequest request)
      Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request. The global context will be found via the ServletContext or via ContextLoader's current context.
      参数:
      request - current HTTP request
      返回:
      the request-specific WebApplicationContext, or the global one if no request-specific context has been found, or null if none
      从以下版本开始:
      4.0
      另请参阅:

    • findWebApplicationContext

      @Nullable public static WebApplicationContext findWebApplicationContext(ServletRequest request, @Nullable ServletContext servletContext)
      Look for the WebApplicationContext associated with the DispatcherServlet that has initiated request processing, and for the global context if none was found associated with the current request. The global context will be found via the ServletContext or via ContextLoader's current context.

      NOTE: This variant remains compatible with Servlet 2.5, explicitly checking a given ServletContext instead of deriving it from the request.

      参数:
      request - current HTTP request
      servletContext - current servlet context
      返回:
      the request-specific WebApplicationContext, or the global one if no request-specific context has been found, or null if none
      从以下版本开始:
      4.0
      另请参阅:

    • getSessionId

      @Nullable public static String getSessionId(HttpServletRequest request)
      Determine the session id of the given request, if any.
      参数:
      request - current HTTP request
      返回:
      the session id, or null if none
      从以下版本开始:
      4.0

    • getSessionAttribute

      @Nullable public static Object getSessionAttribute(HttpServletRequest request, String name)
      Check the given request for a session attribute of the given name. Returns null if there is no session or if the session has no such attribute. Does not create a new session if none has existed before!
      参数:
      request - current HTTP request
      name - the name of the session attribute
      返回:
      the value of the session attribute, or null if not found
      从以下版本开始:
      4.0

    • getRequiredSessionAttribute

      public static Object getRequiredSessionAttribute(HttpServletRequest request, String name)
      Check the given request for a session attribute of the given name. Throws an exception if there is no session or if the session has no such attribute. Does not create a new session if none has existed before!
      参数:
      request - current HTTP request
      name - the name of the session attribute
      返回:
      the value of the session attribute, or null if not found
      抛出:
      IllegalStateException - if the session attribute could not be found
      从以下版本开始:
      4.0

    • setSessionAttribute

      public static void setSessionAttribute(HttpServletRequest request, String name, @Nullable Object value)
      Set the session attribute with the given name to the given value. Removes the session attribute if value is null, if a session existed at all. Does not create a new session if not necessary!
      参数:
      request - current HTTP request
      name - the name of the session attribute
      value - the value of the session attribute
      从以下版本开始:
      4.0

    • getSessionMutex

      public static Object getSessionMutex(HttpSession session)
      Return the best available mutex for the given session: that is, an object to synchronize on for the given session.

      Returns the session mutex attribute if available; usually, this means that the HttpSessionMutexListener needs to be defined in web.xml. Falls back to the HttpSession itself if no mutex attribute found.

      The session mutex is guaranteed to be the same object during the entire lifetime of the session, available under the key defined by the SESSION_MUTEX_ATTRIBUTE constant. It serves as a safe reference to synchronize on for locking on the current session.

      In many cases, the HttpSession reference itself is a safe mutex as well, since it will always be the same object reference for the same active logical session. However, this is not guaranteed across different servlet containers; the only 100% safe way is a session mutex.

      参数:
      session - the HttpSession to find a mutex for
      返回:
      the mutex object (never null)
      从以下版本开始:
      4.0
      另请参阅:

    • hasSubmitParameter

      public static boolean hasSubmitParameter(ServletRequest request, String name)
      Check if a specific input type="submit" parameter was sent in the request, either via a button (directly with name) or via an image (name + ".x" or name + ".y").
      参数:
      request - current HTTP request
      name - the name of the parameter
      返回:
      if the parameter was sent
      从以下版本开始:
      4.0
      另请参阅:

    • isIncludeRequest

      public static boolean isIncludeRequest(ServletRequest request)
      Determine whether the given request is an include request, that is, not a top-level HTTP request coming in from the outside.

      Checks the presence of the "jakarta.servlet.include.request_uri" request attribute. Could check any request attribute that is only present in an include request.

      参数:
      request - current servlet request
      返回:
      whether the given request is an include request
      从以下版本开始:
      4.0

    • isPostForm

      public static boolean isPostForm(HttpServletRequest request)
      从以下版本开始:
      4.0

    • getCookie

      @Nullable public static Cookie getCookie(HttpServletRequest request, String name)
      Retrieve the first cookie with the given name. Note that multiple cookies can have the same name but different paths or domains.
      参数:
      request - current servlet request
      name - cookie name
      返回:
      the first cookie with the given name, or null if none is found
      从以下版本开始:
      4.0

    • getParametersStartingWith

      public static Map<String,Object> getParametersStartingWith(ServletRequest request, @Nullable String prefix)
      Return a map containing all parameters with the given prefix. Maps single values to String and multiple values to String array.

      For example, with a prefix of "spring_", "spring_param1" and "spring_param2" result in a Map with "param1" and "param2" as keys.

      参数:
      request - the HTTP request in which to look for parameters
      prefix - the beginning of parameter names (if this is null or the empty string, all parameters will match)
      返回:
      map containing request parameters without the prefix, containing either a String or a String array as values
      另请参阅:

    • findParameterValue

      @Nullable public static String findParameterValue(ServletRequest request, String name)
      Obtain a named parameter from the given request parameters.

      See findParameterValue(Map, String) for a description of the lookup algorithm.

      参数:
      request - current HTTP request
      name - the logical name of the request parameter
      返回:
      the value of the parameter, or null if the parameter does not exist in given request

    • findParameterValue

      @Nullable public static String findParameterValue(Map<String,?> parameters, String name)
      Obtain a named parameter from the given request parameters.

      This method will try to obtain a parameter value using the following algorithm:

      1. Try to get the parameter value using just the given logical name. This handles parameters of the form logicalName = value. For normal parameters, e.g. submitted using a hidden HTML form field, this will return the requested value.
      2. Try to obtain the parameter value from the parameter name, where the parameter name in the request is of the form logicalName_value = xyz with "_" being the configured delimiter. This deals with parameter values submitted using an HTML form submit button.
      3. If the value obtained in the previous step has a ".x" or ".y" suffix, remove that. This handles cases where the value was submitted using an HTML form image button. In this case the parameter in the request would actually be of the form logicalName_value.x = 123.
      参数:
      parameters - the available parameter map
      name - the logical name of the request parameter
      返回:
      the value of the parameter, or null if the parameter does not exist in given request

    • exposeErrorRequestAttributes

      public static void exposeErrorRequestAttributes(HttpServletRequest request, Throwable ex, @Nullable String servletName)
      Expose the Servlet spec's error attributes as HttpServletRequest attributes under the keys defined in the Servlet 2.3 specification, for error pages that are rendered directly rather than through the Servlet container's error page resolution: jakarta.servlet.error.status_code, jakarta.servlet.error.exception_type, jakarta.servlet.error.message, jakarta.servlet.error.exception, jakarta.servlet.error.request_uri, jakarta.servlet.error.servlet_name.

      Does not override values if already present, to respect attribute values that have been exposed explicitly before.

      Exposes status code 200 by default. Set the "jakarta.servlet.error.status_code" attribute explicitly (before or after) in order to expose a different status code.

      参数:
      request - current servlet request
      ex - the exception encountered
      servletName - the name of the offending servlet
      从以下版本开始:
      4.0

    • exposeRequestAttributeIfNotPresent

      private static void exposeRequestAttributeIfNotPresent(ServletRequest request, String name, Object value)
      Expose the specified request attribute if not already present.
      参数:
      request - current servlet request
      name - the name of the attribute
      value - the suggested value of the attribute
      从以下版本开始:
      4.0

    • clearErrorRequestAttributes

      public static void clearErrorRequestAttributes(HttpServletRequest request)
      Clear the Servlet spec's error attributes as HttpServletRequest attributes under the keys defined in the Servlet 2.3 specification: jakarta.servlet.error.status_code, jakarta.servlet.error.exception_type, jakarta.servlet.error.message, jakarta.servlet.error.exception, jakarta.servlet.error.request_uri, jakarta.servlet.error.servlet_name.
      参数:
      request - current servlet request
      从以下版本开始:
      4.0

    • setWebAppRootSystemProperty

      public static void setWebAppRootSystemProperty(ServletContext servletContext) throws IllegalStateException
      Set a system property to the web application root directory. The key of the system property can be defined with the "webAppRootKey" context-param in web.xml. Default is "webapp.root".

      Can be used for tools that support substitution with System.getProperty values, like log4j's "${key}" syntax within log file locations.

      参数:
      servletContext - the servlet context of the web application
      抛出:
      IllegalStateException - if the system property is already set, or if the WAR file is not expanded
      另请参阅:

    • removeWebAppRootSystemProperty

      public static void removeWebAppRootSystemProperty(ServletContext servletContext)
      Remove the system property that points to the web app root directory. To be called on shutdown of the web application.
      参数:
      servletContext - the servlet context of the web application
      另请参阅:

    • getDefaultHtmlEscape

      @Nullable public static Boolean getDefaultHtmlEscape(@Nullable ServletContext servletContext)
      Return whether default HTML escaping is enabled for the web application, i.e. the value of the "defaultHtmlEscape" context-param in web.xml (if any).

      This method differentiates between no param specified at all and an actual boolean value specified, allowing to have a context-specific default in case of no setting at the global level.

      参数:
      servletContext - the servlet context of the web application
      返回:
      whether default HTML escaping is enabled for the given application (null = no explicit default)

    • getResponseEncodedHtmlEscape

      @Nullable public static Boolean getResponseEncodedHtmlEscape(@Nullable ServletContext servletContext)
      Return whether response encoding should be used when HTML escaping characters, thus only escaping XML markup significant characters with UTF-* encodings. This option is enabled for the web application with a ServletContext param, i.e. the value of the "responseEncodedHtmlEscape" context-param in web.xml (if any).

      This method differentiates between no param specified at all and an actual boolean value specified, allowing to have a context-specific default in case of no setting at the global level.

      参数:
      servletContext - the servlet context of the web application
      返回:
      whether response encoding is to be used for HTML escaping (null = no explicit default)
      从以下版本开始:
      4.0

    • getTempDir

      public static File getTempDir(ServletContext servletContext)
      Return the temporary directory for the current web application, as provided by the servlet container.
      参数:
      servletContext - the servlet context of the web application
      返回:
      the File representing the temporary directory

    • getRealPath

      public static String getRealPath(ServletContext servletContext, String path) throws FileNotFoundException
      Return the real path of the given path within the web application, as provided by the servlet container.

      Prepends a slash if the path does not already start with a slash, and throws a FileNotFoundException if the path cannot be resolved to a resource (in contrast to ServletContext's getRealPath, which returns null).

      参数:
      servletContext - the servlet context of the web application
      path - the path within the web application
      返回:
      the corresponding real path
      抛出:
      FileNotFoundException - if the path cannot be resolved to a resource
      另请参阅:

    • getParts

      public static cn.taketoday.util.MultiValueMap<String,Part> getParts(HttpServletRequest request) throws MultipartException
      Retrieve all parts from the given servlet request.
      参数:
      request - the servlet request
      返回:
      the parts in a MultiValueMap
      抛出:
      MultipartException - in case of failures
      从以下版本开始:
      4.0

    • getParts

      public static List<Part> getParts(HttpServletRequest request, String name) throws MultipartException
      Retrieve all parts with the given name from the given servlet request.
      参数:
      request - the servlet request
      name - the name to look for
      返回:
      the parts in a MultiValueMap
      抛出:
      MultipartException - in case of failures
      从以下版本开始:
      4.0

    • getPart

      public static Part getPart(RequestContext request, String requestPartName)

    • getPart

      public static Part getPart(HttpServletRequest request, String requestPartName)

    • bindParts

      public static void bindParts(HttpServletRequest request, cn.taketoday.beans.PropertyValues mpvs, boolean bindEmpty) throws MultipartException
      Bind all parts from the given servlet request.
      参数:
      request - the servlet request
      mpvs - the property values to bind to
      bindEmpty - whether to bind empty parts as well
      抛出:
      MultipartException - in case of failures
      从以下版本开始:
      4.0