Package org.apache.catalina.filters

Class SetCharacterEncodingFilter

  • All Implemented Interfaces:
    Filter
    public class SetCharacterEncodingFilter
extends FilterBase

    Example filter that sets the character encoding to be used in parsing the incoming request, either unconditionally or only if the client did not specify a character encoding. Configuration of this filter is based on the following initialization parameters:

    • encoding - The character encoding to be configured for this request, either conditionally or unconditionally based on the ignore initialization parameter. This parameter is required, so there is no default.
    • ignore - If set to "true", any character encoding specified by the client is ignored, and the value returned by the selectEncoding() method is set. If set to "false, selectEncoding() is called only if the client has not already specified an encoding. By default, this parameter is set to "false".

    Although this filter can be used unchanged, it is also easy to subclass it and make the selectEncoding() method more intelligent about what encoding to choose, based on characteristics of the incoming request (such as the values of the Accept-Language and User-Agent headers, or a value stashed in the current user's session).

    • Field Summary

      • Fields inherited from class org.apache.catalina.filters.FilterBase

        sm

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void doFilter​(ServletRequest request, ServletResponse response, FilterChain chain)
      Select and set (if specified) the character encoding to be used to interpret request parameters for this request.
      java.lang.String getEncoding()
      Returns the character encoding configured for this filter.
      protected Log getLogger()
      Returns the logger used by this filter.
      boolean isIgnore()
      Returns whether client-specified character encodings are ignored.
      protected java.lang.String selectEncoding​(ServletRequest request)
      Select an appropriate character encoding to be used, based on the characteristics of the current request and/or filter initialization parameters.
      void setEncoding​(java.lang.String encoding)
      Sets the character encoding to be configured for requests.
      void setIgnore​(boolean ignore)
      Sets whether to ignore any character encoding specified by the client.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • SetCharacterEncodingFilter

        public SetCharacterEncodingFilter()
        Default constructor.

    • Method Detail

      • setEncoding

        public void setEncoding​(java.lang.String encoding)
        Sets the character encoding to be configured for requests.
        Parameters:
        encoding - the character encoding

      • getEncoding

        public java.lang.String getEncoding()
        Returns the character encoding configured for this filter.
        Returns:
        the character encoding

      • setIgnore

        public void setIgnore​(boolean ignore)
        Sets whether to ignore any character encoding specified by the client.
        Parameters:
        ignore - true to ignore client-specified encoding

      • isIgnore

        public boolean isIgnore()
        Returns whether client-specified character encodings are ignored.
        Returns:
        true if client encodings are ignored

      • doFilter

        public void doFilter​(ServletRequest request,
                     ServletResponse response,
                     FilterChain chain)
              throws java.io.IOException,
                     ServletException
        Select and set (if specified) the character encoding to be used to interpret request parameters for this request.
        Parameters:
        request - The servlet request we are processing
        response - The servlet response we are creating
        chain - The filter chain we are processing
        Throws:
        java.io.IOException - if an input/output error occurs
        ServletException - if a servlet error occurs

      • getLogger

        protected Log getLogger()
        Returns the logger used by this filter.
        Specified by:
        getLogger in class FilterBase
        Returns:
        the logger instance

      • selectEncoding

        protected java.lang.String selectEncoding​(ServletRequest request)
        Select an appropriate character encoding to be used, based on the characteristics of the current request and/or filter initialization parameters. If no character encoding should be set, return null.

        The default implementation unconditionally returns the value configured by the encoding initialization parameter for this filter.

        Parameters:
        request - The servlet request we are processing
        Returns:
        the encoding that was configured