From 6dba75bee6954a0185515b6da63b592a511b3169 Mon Sep 17 00:00:00 2001
From: Thorsten Vitt <thorsten.vitt@uni-wuerzburg.de>
Date: Sun, 19 Jan 2014 18:25:37 +0100
Subject: [PATCH] Adjusted StylesheetManager to Cache API.
---
.../aggregator/StylesheetManager.java | 90 ++++++++++++++-----
1 file changed, 67 insertions(+), 23 deletions(-)
diff --git a/src/main/java/info/textgrid/services/aggregator/StylesheetManager.java b/src/main/java/info/textgrid/services/aggregator/StylesheetManager.java
index 3e369d7..cce4c65 100644
--- a/src/main/java/info/textgrid/services/aggregator/StylesheetManager.java
+++ b/src/main/java/info/textgrid/services/aggregator/StylesheetManager.java
@@ -11,6 +11,8 @@
import java.net.URL;
import java.text.MessageFormat;
import java.util.Set;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
import java.util.logging.Level;
import java.util.logging.Logger;
@@ -23,6 +25,7 @@
import net.sf.saxon.s9api.XsltExecutable;
import com.google.common.base.Optional;
+import com.google.common.base.Throwables;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
@@ -35,7 +38,8 @@
/**
* Manages and caches XSLT stylesheets across service calls, also maintains
* processor policies etc. All stylesheets invoked throughout the service should
- * be invoked through the manager's {@link #getStylesheet(URI, Optional, boolean, boolean)} method.
+ * be invoked through the manager's
+ * {@link #getStylesheet(URI, Optional, boolean, boolean)} method.
*/
public class StylesheetManager {
private static final Logger logger = Logger
@@ -132,25 +136,50 @@ public XsltExecutable load(final URI url) throws Exception {
public XsltExecutable getStylesheet(final URI uri,
final Optional<String> sid, final boolean forceLoad,
final boolean frequentlyUsed) throws SaxonApiException, IOException {
- XsltExecutable executable = null;
- // (1) try cached version, if it exists
- if (!forceLoad) {
- executable = stylesheets.getIfPresent(uri);
+ if (frequentlyUsed)
+ importantStylesheets.add(uri);
+
+ try {
+ if (forceLoad)
+ stylesheets.invalidate(uri);
+
+ return stylesheets.get(uri, new StylesheetLoader(uri, sid));
+ } catch (final ExecutionException e) {
+ final Throwable cause = e.getCause();
+ if (cause instanceof PrivateResourceException)
+ return ((PrivateResourceException) cause).getXsltExecutable();
+ else {
+ Throwables.propagateIfPossible(cause, SaxonApiException.class,
+ IOException.class);
+ return null; // will never be reached
+ }
+
}
- if (executable == null) {
- if (frequentlyUsed)
- importantStylesheets.add(uri);
+ }
- final XsltCompiler compiler = xsltProcessor.newXsltCompiler();
+ private final class StylesheetLoader implements Callable<XsltExecutable> {
+ private final URI uri;
+ private final Optional<String> sid;
- // (2) it's internal, load & cache it from the servlet
+ private StylesheetLoader(final URI uri, final Optional<String> sid) {
+ this.uri = uri;
+ this.sid = sid;
+ }
+
+ @Override
+ public XsltExecutable call() throws Exception {
+ final XsltCompiler compiler = xsltProcessor.newXsltCompiler();
+ final XsltExecutable executable;
if (uri.getScheme() == null || uri.getScheme() == "file") {
+ // (1) Internal
final URL resource = resolveInternalPath(uri.getPath());
- executable = compiler.compile(new StreamSource(resource.openStream(), resource.toExternalForm()));
- stylesheets.put(uri, executable);
- logger.log(Level.INFO, "Cached internal stylesheet {0}", resource);
+ executable = compiler.compile(new StreamSource(resource
+ .openStream(), resource.toExternalForm()));
+ logger.log(Level.INFO, "Cached internal stylesheet {0}",
+ resource);
+ return executable;
} else if (TGUriResolver.isResolveable(uri)) {
// (3/4) it's a TextGrid object, load it from TG-crud.
@@ -161,26 +190,39 @@ public XsltExecutable getStylesheet(final URI uri,
if (isPublic(xsltSupplier.getMetadata())) {
// (3) it's public -> we can cache it.
- stylesheets.put(uri, executable);
logger.log(Level.INFO, "Cached public stylesheet {0}", uri);
+ return executable;
} else {
- // (4) it's private -> no caching
logger.log(Level.INFO, "Loaded private stylesheet {0}", uri);
+ throw new PrivateResourceException(executable);
}
} else {
// (2) it's non-TextGrid -- load & cache it.
executable = compiler.compile(new StreamSource(uri.toString()));
- stylesheets.put(uri, executable);
logger.log(Level.INFO, "Cached external stylesheet {0}", uri);
+ return executable;
}
- } else {
- logger.log(Level.INFO, "Reusing cached stylesheed {0}", uri);
}
+ }
+
+ private static class PrivateResourceException extends Exception {
- return executable;
+ private static final long serialVersionUID = -3506322226718139009L;
+ private XsltExecutable xsltExecutable;
+
+ public XsltExecutable getXsltExecutable() {
+ return xsltExecutable;
+ }
+
+ public PrivateResourceException(final XsltExecutable xsltExecutable) {
+ super("The source object is private and will not be cached.");
+ this.xsltExecutable = xsltExecutable;
+ }
}
- private URL resolveInternalPath(final String path) throws MalformedURLException {
+
+ private URL resolveInternalPath(final String path)
+ throws MalformedURLException {
URL stylesheet;
if (servlet == null) {
logger.info("No servlet context, trying fallback property");
@@ -192,7 +234,8 @@ private URL resolveInternalPath(final String path) throws MalformedURLException
} else {
stylesheet = servlet.getResource(path);
}
- logger.fine("Resolved internal stylesheet: " + stylesheet.toExternalForm());
+ logger.fine("Resolved internal stylesheet: "
+ + stylesheet.toExternalForm());
return stylesheet;
}
@@ -208,7 +251,9 @@ private static boolean isPublic(final ObjectType metadata) {
@Override
protected void finalize() throws Throwable {
if (stylesheets != null)
- logger.log(Level.INFO, "Shutting down stylesheet manager. Stats: {0}", stylesheets.stats());
+ logger.log(Level.INFO,
+ "Shutting down stylesheet manager. Stats: {0}",
+ stylesheets.stats());
super.finalize();
}
@@ -216,5 +261,4 @@ public CacheStats stats() {
return stylesheets.stats();
}
-
}
\ No newline at end of file
--
GitLab