jodd.servlet.filter

Class GzipFilter

java.lang.Object

jodd.servlet.filter.GzipFilter

All Implemented Interfaces:

javax.servlet.Filter

public class GzipFilter
extends java.lang.Object
implements javax.servlet.Filter

Compresses output with GZIP, for browsers that supports it.

Configuration is based on the following initialization parameters:

• threshold - min number of bytes for compressing or 0 for no compression at all. By defaults is 0. Good value is 128.
• match - comma separated string patterns to be found in the uri for using gzip. Only uris that match these patterns will be gzipped. Use '*' to enable default matching using just extensions. extensions (ignoring the wildcards value)
• extensions - when match is set to all resources, this parameter defines list of URI extensions that should be gzipped. By default set to: html, htm, css, js. Use '*' to match all extensions.
• exclude - comma separated string patterns to be excluded if found in uri for using gzip. It is applied only if all urls are matched.
• wildcards - boolean that specifies wildcard matching for string patterns. by default false. URL is matched as paths.
• requestParameterName - name of request parameter that can override GZipping. Default value is gzip. Set it to an empty string to turn this feature off.

All matching is done in lowercase. You can override this class for finer control.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.String[]	excludes
protected java.lang.String[]	extensions
protected java.lang.String[]	matches
protected java.lang.String	requestParameterName
protected int	threshold
protected boolean	wildcards

Constructor Summary

Constructors

Constructor and Description
GzipFilter()

Method Summary

Modifier and Type	Method and Description
void	destroy()
void	doFilter(javax.servlet.ServletRequest request, javax.servlet.ServletResponse response, javax.servlet.FilterChain chain) If browser supports gzip, sets the Content-Encoding response header and invoke resource with a wrapped response that collects all the output.
void	init(javax.servlet.FilterConfig config) Filter initialization.
protected boolean	isGzipEligible(javax.servlet.http.HttpServletRequest request) Determine if request is eligible for GZipping.

Methods inherited from class java.lang.Object

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

Field Detail

threshold

protected int threshold

matches

protected java.lang.String[] matches

excludes

protected java.lang.String[] excludes

wildcards

protected boolean wildcards

requestParameterName

protected java.lang.String requestParameterName

extensions

protected java.lang.String[] extensions

Constructor Detail

GzipFilter

public GzipFilter()

Method Detail

doFilter

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

If browser supports gzip, sets the Content-Encoding response header and invoke resource with a wrapped response that collects all the output. Extracts the output and write it into a gzipped byte array. Finally, write that array to the client's output stream.

If browser does not support gzip, invokes resource normally.

Specified by:

doFilter in interface javax.servlet.Filter

Throws:

javax.servlet.ServletException

java.io.IOException

init

public void init(javax.servlet.FilterConfig config)

Filter initialization.

Specified by:

init in interface javax.servlet.Filter

destroy

public void destroy()

Specified by:

destroy in interface javax.servlet.Filter

isGzipEligible

protected boolean isGzipEligible(javax.servlet.http.HttpServletRequest request)

Determine if request is eligible for GZipping.