Attached revised fix.
Jeremias Maerki wrote:
Adrian,
you forgot to account for the case where the GC removes the instance in
the worst possible moment and WeakReference.get() returns null.
On 20.07.2007 16:33:34 Adrian Cumiskey wrote:
Index: src/java/org/apache/fop/fo/properties/PropertyCache.java
===================================================================
--- src/java/org/apache/fop/fo/properties/PropertyCache.java (revision
555659)
+++ src/java/org/apache/fop/fo/properties/PropertyCache.java (working copy)
@@ -19,6 +19,7 @@
package org.apache.fop.fo.properties;
+import java.lang.ref.WeakReference;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
@@ -39,16 +40,16 @@
* Checks if the given property is present in the cache - if so, returns
* a reference to the cached value. Otherwise the given object is added
* to the cache and returned.
- * @param obj
+ * @param prop a property
* @return the cached instance
*/
public Property fetch(Property prop) {
-
- Property cacheEntry = (Property) propCache.get(prop);
- if (cacheEntry != null) {
+ WeakReference ref = (WeakReference) propCache.get(prop);
+ if (ref != null) {
+ Property cacheEntry = (Property)ref.get();
return cacheEntry;
} else {
- propCache.put(prop, prop);
+ propCache.put(prop, new WeakReference(prop));
return prop;
}
}
Jeremias Maerki
Index: src/java/org/apache/fop/fo/properties/PropertyCache.java
===================================================================
--- src/java/org/apache/fop/fo/properties/PropertyCache.java (revision
555659)
+++ src/java/org/apache/fop/fo/properties/PropertyCache.java (working copy)
@@ -19,6 +19,7 @@
package org.apache.fop.fo.properties;
+import java.lang.ref.WeakReference;
import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;
@@ -39,17 +40,18 @@
* Checks if the given property is present in the cache - if so, returns
* a reference to the cached value. Otherwise the given object is added
* to the cache and returned.
- * @param obj
+ * @param prop a property
* @return the cached instance
*/
public Property fetch(Property prop) {
-
- Property cacheEntry = (Property) propCache.get(prop);
- if (cacheEntry != null) {
- return cacheEntry;
- } else {
- propCache.put(prop, prop);
- return prop;
+ WeakReference ref = (WeakReference) propCache.get(prop);
+ if (ref != null) {
+ Property cacheEntry = (Property)ref.get();
+ if (cacheEntry != null) {
+ return cacheEntry;
+ }
}
+ propCache.put(prop, new WeakReference(prop));
+ return prop;
}
}
