Update config parameter names

* Use a `HttpServletResponseWrapper` to remove HTTP/1.0 `Pragma` header.
* Replace `expirationTime<Long>` parameter with `expiration<Long>`.
* Replace `static<Boolean>` parameter with `must-revalidate<Boolean>`.

Author: samaxes

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Java EE Cache Filter
 
+## 2.2.0
+
+* Use a `HttpServletResponseWrapper` to remove HTTP/1.0 `Pragma` header.
+* Replace `expirationTime<Long>` parameter with `expiration<Long>`.
+* Replace `static<Boolean>` parameter with `must-revalidate<Boolean>`.
+
 ## 2.1.0
 
 * Move from Google Project Hosting (https://code.google.com/p/cache-filter/) to GitHub (https://github.com/samaxes/javaee-cache-filter).
@@ -8,23 +14,23 @@
 
 ## 2.0
 
-* Added `NoETagFilter` class to disable HTTP `ETag` header set by the `DefaultServlet` in Tomcat.
-* Added `NoCacheFilter` class to completely disable browser caching.
-* Replaced `privacy<String>` parameter by `private<Boolean>`. Cache directive to control where the response may be cached.
-* Added `static<Boolean>` parameter. Conditional requests are not required for static components.
+* Add `NoETagFilter` class to disable HTTP `ETag` header set by the `DefaultServlet` in Tomcat.
+* Add `NoCacheFilter` class to completely disable browser caching.
+* Replace `privacy<String>` parameter with `private<Boolean>`. Cache directive to control where the response may be cached.
+* Add `static<Boolean>` parameter. Conditional requests are not required for static components.
   Cache directive `must-revalidate` should be used for non static components to force them to be revalidated once a response becomes stale.
 
 ## 1.2.1
 
-* Optimized the configuration process. All the configurations are now done in the init method.
-* Added the Sonatype OSS Parent POM.
+* Optimize the configuration process. All the configurations are now done in the init method.
+* Add the Sonatype OSS Parent POM.
 
 ## 1.2
 
-* Changed the default package to `com.samaxes.filter`.
-* Updated the distribution repositories to Sonatype Nexus.
+* Change the default package to `com.samaxes.filter`.
+* Update the distribution repositories to Sonatype Nexus.
 
 ## 1.1.0
 
 * Use `response.setDateHeader()` instead of `response.setHeader()` to set `Expires` HTTP cache header.
-* Compiled against JDK 1.5 instead of JDK 1.6.
+* Compile against JDK 1.5 instead of JDK 1.6.

pom.xml

@@ -10,7 +10,7 @@
 
     <groupId>com.samaxes.filter</groupId>
     <artifactId>cachefilter</artifactId>
-    <version>2.1.1-SNAPSHOT</version>
+    <version>2.2.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <name>Java EE Cache Filter</name>

src/main/java/com/samaxes/filter/CacheFilter.java

@@ -27,6 +27,7 @@
 import javax.servlet.ServletRequest;
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletResponse;
+import javax.servlet.http.HttpServletResponseWrapper;
 
 import com.samaxes.filter.util.CacheConfigParameter;
 import com.samaxes.filter.util.Cacheability;
@@ -137,61 +138,85 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public class CacheFilter implements Filter {
 
-    private Cacheability cacheability;
+    private long expiration;
 
-    private boolean isStatic;
+    private Cacheability cacheability;
 
-    private long seconds;
+    private boolean mustRevalidate;
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void init(FilterConfig filterConfig) throws ServletException {
-        cacheability = (Boolean.valueOf(filterConfig.getInitParameter(CacheConfigParameter.PRIVATE.getName()))) ? Cacheability.PRIVATE
-                : Cacheability.PUBLIC;
-        isStatic = Boolean.valueOf(filterConfig.getInitParameter(CacheConfigParameter.STATIC.getName()));
+        if (filterConfig.getInitParameter("expirationTime") != null) {
+            throw new ServletException(new StringBuilder(
+                    "The initialization parameter expirationTime has been replaced with ")
+                    .append(CacheConfigParameter.EXPIRATION.getName()).append(" for the filter ")
+                    .append(filterConfig.getFilterName()).append(".").toString());
+        }
+        if (filterConfig.getInitParameter("static") != null) {
+            throw new ServletException(new StringBuilder("The initialization parameter static has been replaced with ")
+                    .append(CacheConfigParameter.MUST_REVALIDATE.getName()).append(" for the filter ")
+                    .append(filterConfig.getFilterName()).append(".").toString());
+        }
 
         try {
-            seconds = Long.valueOf(filterConfig.getInitParameter(CacheConfigParameter.EXPIRATION_TIME.getName()));
+            expiration = Long.valueOf(filterConfig.getInitParameter(CacheConfigParameter.EXPIRATION.getName()));
         } catch (NumberFormatException e) {
             throw new ServletException(new StringBuilder("The initialization parameter ")
-                    .append(CacheConfigParameter.EXPIRATION_TIME.getName()).append(" is missing for filter ")
-                    .append(filterConfig.getFilterName()).append(".").toString());
+                    .append(CacheConfigParameter.EXPIRATION.getName())
+                    .append(" is invalid or is missing for the filter ").append(filterConfig.getFilterName())
+                    .append(".").toString());
         }
+        cacheability = Boolean.valueOf(filterConfig.getInitParameter(CacheConfigParameter.PRIVATE.getName())) ? Cacheability.PRIVATE
+                : Cacheability.PUBLIC;
+        mustRevalidate = Boolean.valueOf(filterConfig.getInitParameter(CacheConfigParameter.MUST_REVALIDATE.getName()));
     }
 
     /**
-     * Set cache header directives. {@inheritDoc}
+     * <p>
+     * Set HTTP cache headers.
+     * </p>
+     * {@inheritDoc}
      */
     @Override
     public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
             throws IOException, ServletException {
         HttpServletResponse httpServletResponse = (HttpServletResponse) servletResponse;
-        StringBuilder cacheControl = new StringBuilder(cacheability.getValue()).append(", max-age=").append(seconds);
-
-        if (!isStatic) {
+        StringBuilder cacheControl = new StringBuilder(cacheability.getValue()).append(", max-age=").append(expiration);
+        if (mustRevalidate) {
             cacheControl.append(", must-revalidate");
         }
 
         // Set cache directives
         httpServletResponse.setHeader(HTTPCacheHeader.CACHE_CONTROL.getName(), cacheControl.toString());
-        httpServletResponse.setDateHeader(HTTPCacheHeader.EXPIRES.getName(), System.currentTimeMillis() + seconds
+        httpServletResponse.setDateHeader(HTTPCacheHeader.EXPIRES.getName(), System.currentTimeMillis() + expiration
                 * 1000L);
 
         /*
-         * By default, some servers (e.g. Tomcat) will set headers on any SSL content to deny caching. Setting the
-         * Pragma header to null or to an empty string takes care of user-agents implementing HTTP 1.0.
+         * By default, some servers (e.g. Tomcat) will set headers on any SSL content to deny caching. Omitting the
+         * Pragma header takes care of user-agents implementing HTTP/1.0.
          */
-        if (httpServletResponse.containsHeader("Pragma")) {
-            httpServletResponse.setHeader(HTTPCacheHeader.PRAGMA.getName(), null);
-        }
+        filterChain.doFilter(servletRequest, new HttpServletResponseWrapper(httpServletResponse) {
+            @Override
+            public void addHeader(String name, String value) {
+                if (!HTTPCacheHeader.PRAGMA.getName().equalsIgnoreCase(name)) {
+                    super.addHeader(name, value);
+                }
+            }
 
-        filterChain.doFilter(servletRequest, servletResponse);
+            @Override
+            public void setHeader(String name, String value) {
+                if (!HTTPCacheHeader.PRAGMA.getName().equalsIgnoreCase(name)) {
+                    super.setHeader(name, value);
+                }
+            }
+        });
     }
 
     /**

src/main/java/com/samaxes/filter/NoCacheFilter.java

@@ -59,7 +59,7 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public class NoCacheFilter implements Filter {
 
@@ -71,7 +71,10 @@ public void init(FilterConfig filterConfig) throws ServletException {
     }
 
     /**
-     * Set cache header directives. {@inheritDoc}
+     * <p>
+     * Set HTTP cache headers.
+     * </p>
+     * {@inheritDoc}
      */
     @Override
     public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)

src/main/java/com/samaxes/filter/NoETagFilter.java

@@ -58,7 +58,7 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public class NoETagFilter implements Filter {
 
@@ -70,7 +70,10 @@ public void init(FilterConfig filterConfig) throws ServletException {
     }
 
     /**
-     * Disables {@code ETag} HTTP header. {@inheritDoc}
+     * <p>
+     * Disables {@code ETag} HTTP header.
+     * </p>
+     * {@inheritDoc}
      */
     @Override
     public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)

src/main/java/com/samaxes/filter/util/CacheConfigParameter.java

@@ -23,21 +23,21 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public enum CacheConfigParameter {
     /**
-     * Defines whether a component is static or not.
+     * Cache directive to set an expiration time, in seconds, relative to the current date.
      */
-    STATIC("static"),
+    EXPIRATION("expiration"),
     /**
      * Cache directive to control where the response may be cached.
      */
     PRIVATE("private"),
     /**
-     * Cache directive to set an expiration date relative to the current date.
+     * Cache directive to define whether conditional requests are required or not for stale responses.
      */
-    EXPIRATION_TIME("expirationTime");
+    MUST_REVALIDATE("must-revalidate");
 
     private final String name;
 

src/main/java/com/samaxes/filter/util/Cacheability.java

@@ -23,7 +23,7 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public enum Cacheability {
     /**

src/main/java/com/samaxes/filter/util/HTTPCacheHeader.java

@@ -23,7 +23,7 @@
  *
  * @author Samuel Santos
  * @author John Yeary
- * @version 2.1.0
+ * @version 2.2.0
  */
 public enum HTTPCacheHeader {
     /**