Package org.apache.catalina.ssi

## Class SSIFilter

- java.lang.Object
- - jakarta.servlet.GenericFilter
  - - org.apache.catalina.ssi.SSIFilter

- All Implemented Interfaces:
    `Filter`, `FilterConfig`, `java.io.Serializable`

      public class SSIFilter
      extends GenericFilter

  Filter to process SSI requests within a webpage. Mapped to a content types from within web.xml.
  Author:
    David Becker
  See Also:
    `SSIServlet`, Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `protected boolean` | `allowExec` | Allow exec (normally blocked for security)
    `protected java.util.regex.Pattern` | `contentTypeRegEx` | regex pattern to match when evaluating content types
    `protected int` | `debug` | Debug level for this servlet.
    `protected java.lang.Long` | `expires` | Expiration time in seconds for the doc.
    `protected boolean` | `isVirtualWebappRelative` | virtual path can be webapp-relative
    `protected java.util.regex.Pattern` | `shtmlRegEx` | default pattern for ssi filter content type matching

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `SSIFilter()` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `doFilter​(ServletRequest request, ServletResponse response, FilterChain chain)` | The `doFilter` method of the Filter is called by the container each time a request/response pair is passed through the chain due to a client request for a resource at the end of the chain.
    `void` | `init()` | Convenience method for sub-classes to save them having to call `super.init(config)`.

    - ### Methods inherited from class jakarta.servlet.GenericFilter

      `getFilterConfig, getFilterName, getInitParameter, getInitParameterNames, getServletContext, init`

    - ### Methods inherited from class java.lang.Object

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

    - ### Methods inherited from interface jakarta.servlet.Filter

      `destroy`

- - ### Field Detail

    - #### debug

          protected int debug

      Debug level for this servlet.

    - #### expires

          protected java.lang.Long expires

      Expiration time in seconds for the doc.

    - #### isVirtualWebappRelative

          protected boolean isVirtualWebappRelative

      virtual path can be webapp-relative

    - #### contentTypeRegEx

          protected java.util.regex.Pattern contentTypeRegEx

      regex pattern to match when evaluating content types

    - #### shtmlRegEx

          protected final java.util.regex.Pattern shtmlRegEx

      default pattern for ssi filter content type matching

    - #### allowExec

          protected boolean allowExec

      Allow exec (normally blocked for security)

  - ### Constructor Detail

    - #### SSIFilter

          public SSIFilter()

  - ### Method Detail

    - #### init

          public void init()
                    throws ServletException

      Description copied from class: `jakarta.servlet.GenericFilter`
      Convenience method for sub-classes to save them having to call `super.init(config)`. This is a NO-OP by default.
      Overrides:
        `init` in class `GenericFilter`
      Throws:
        `ServletException` - If an exception occurs that interrupts the Filter's normal operation

    - #### doFilter

          public void doFilter​(ServletRequest request,
                               ServletResponse response,
                               FilterChain chain)
                        throws java.io.IOException,
                               ServletException

      Description copied from interface: `jakarta.servlet.Filter`
      The `doFilter` method of the Filter is called by the container each time a request/response pair is passed through the chain due to a client request for a resource at the end of the chain. The FilterChain passed in to this method allows the Filter to pass on the request and response to the next entity in the chain.

      A typical implementation of this method would follow the following pattern:-
      1. Examine the request
      2. Optionally wrap the request object with a custom implementation to filter content or headers for input filtering
      3. Optionally wrap the response object with a custom implementation to filter content or headers for output filtering
      4. a) Either invoke the next entity in the chain using the FilterChain object (`chain.doFilter()`),
      4. b) or not pass on the request/response pair to the next entity in the filter chain to block the request processing
      5. Directly set headers on the response after invocation of the next entity in the filter chain.

      Parameters:
        `request` - The request to process
        `response` - The response associated with the request
        `chain` - Provides access to the next filter in the chain for this filter to pass the request and response to for further processing
      Throws:
        `java.io.IOException` - if an I/O error occurs during this filter's processing of the request
        `ServletException` - if the processing fails for any other reason