cocoon-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Pier Fumagalli <p...@betaversion.org>
Subject SitemapSource problems
Date Thu, 30 Sep 2004 15:32:10 GMT
While playing around with the IncludeTransformer, to generate an XSLT  
stylesheet from a bunch of included sources and so on, I stepped on a  
"little" problem in the SitemapSource.

Basically, the XSLTProcessor (I assume that the same behavior might  
happen in other components as well), caches the source and its validity  
as soon as it gets a hold on them, even _before_ actually reading the  
XSLT from the source.

Now, the problem is that within the SitemapSource, sometimes (when, for  
example, one of the elements in a pipeline is an IncludeTransformer),  
the "validity" instance gets reset, and therefore (in the example of  
the XSLTProcessor), the validity acquired before producing XML data  
from the content is a different instance from the validity instance I  
acquire AFTER producing the XML.

The problem is that if I don't re-update the validity instance after  
reding the data, I am going to get a wrong validity, one that will  
never be valid, in some cases, as the content associated with that  
validity has never been generated.

Now, the problem lies in the fact that the "init()" and  
"reset()/refresh()" methods change the instance of the validity  
returned by "getValidity()".

I patched this behavior by basically nesting the calculated validity in  
an instance which will always be returned to the caller, so, that from  
the outside, it doesn't matter whether the source got internally  
refreshed, the instance they can see is _always_ the same.

The only time when the validity instance is (re)created is at  
construction and in the "recycle()" method...

Attached here is a patch which fixes this behavior, and allows  
cacheability of (for example) XSLT templates generated by pipelines  
using the IncludeTransformer.

Given this is a kind of a "biggie", I'd like to have someone to review  
it before applying it to the tree... I'd suspect this might also fix  
some other problems somewhere else...

	Pier

/src/java/org/apache/cocoon/components/source/impl/SitemapSource.java  
SitemapSource.java
---  
/Users/pier/Workspace/cocoon-2.1/src/java/org/apache/cocoon/components/ 
source/impl/SitemapSource.java       Wed Sep 22 00:24:47 2004
+++ SitemapSource.java  Thu Sep 30 16:10:50 2004
@@ -60,7 +60,7 @@
  implements Source, XMLizable {

      /** validities for the internal pipeline */
-    private SourceValidity sourceValidity;
+    private SitemapSourceValidity validity;

      /** The system id */
      private final String systemId;
@@ -86,9 +86,6 @@
      /** The redirect <code>Source</code> */
      private Source redirectSource;

-    /** Redirect validity */
-    private SourceValidity redirectValidity;
-
      /** The <code>SAXException</code> if unable to get resource */
      private SAXException exception;

@@ -208,6 +205,9 @@
               
this.environment.getObjectModel().remove(ObjectModelHelper.PARENT_CONTEX 
T);
          }

+        // create a new validity holder
+        this.validity = new SitemapSourceValidity(this);
+
          // initialize
          this.init();
      }
@@ -300,10 +300,7 @@
       *  <code>null</code> is returned.
       */
      public SourceValidity getValidity() {
-        if (this.redirectSource != null) {
-            return this.redirectValidity;
-        }
-        return this.sourceValidity;
+        return this.validity;
      }

      /**
@@ -343,7 +340,7 @@
                                                           
this.pipelineProcessor);
                  try {
                       
this.processingPipeline.prepareInternal(this.environment);
-                    this.sourceValidity =  
this.processingPipeline.getValidityForEventPipeline();
+                     
this.validity.set(this.processingPipeline.getValidityForEventPipeline()) 
;
                      this.mimeType = this.environment.getContentType();

                      final String eventPipelineKey =  
this.processingPipeline.getKeyForEventPipeline();
@@ -371,7 +368,7 @@
                      this.sourceResolver = (SourceResolver)  
this.manager.lookup(SourceResolver.ROLE);
                  }
                  this.redirectSource =  
this.sourceResolver.resolveURI(redirectURL);
-                this.redirectValidity =  
this.redirectSource.getValidity();
+                this.validity.set(this.redirectSource.getValidity());
                  this.mimeType = this.redirectSource.getMimeType();
              }
          } catch (SAXException e) {
@@ -450,8 +447,7 @@
              this.redirectSource = null;
          }

-        this.sourceValidity = null;
-        this.redirectValidity = null;
+        this.validity.set(null);

          this.environment.reset();
          this.exception = null;
@@ -463,6 +459,7 @@
       * Recyclable
       */
      public void recycle() {
+        this.validity = new SitemapSourceValidity(this);
          this.reset();
          if (this.sourceResolver != null) {
              this.manager.release(this.sourceResolver);
@@ -497,4 +494,37 @@
          return java.util.Collections.EMPTY_LIST.iterator();
      }

+    /**
+     * A simple SourceValidity protecting callers from resets.
+     */
+    public static final class SitemapSourceValidity implements  
SourceValidity {
+
+        public SourceValidity nested_validity = null;
+        public SitemapSource nested_source = null;
+
+        private SitemapSourceValidity(SitemapSource source) {
+            this.nested_source = source;
+        }
+
+        private void set(SourceValidity validity) {
+            this.nested_validity = validity;
+        }
+
+        public int isValid() {
+            return(this.nested_validity != null?
+                   this.nested_validity.isValid():
+                   SourceValidity.INVALID);
+        }
+
+        public int isValid(SourceValidity validity) {
+            return(this.nested_validity != null?
+                   this.nested_validity.isValid(validity):
+                   SourceValidity.INVALID);
+        }
+
+        public String getPath() {
+            if (this.nested_source.systemId == null)  
return("[UNKNOWN]");
+            return(this.nested_source.systemId);
+        }
+    }
  }

Mime
View raw message