Clearing hibernate session factories that leak memory on spring refresh:

dkayiwa · dkayiwa · commit ffc9294f90c4 · 2013-04-30T18:57:01.000+03:00
Investigate possible memory leak in 1.9.0 or one of its bundled modules.
- TRUNK-3440
diff --git a/api/src/main/java/org/openmrs/util/MemoryLeakUtil.java b/api/src/main/java/org/openmrs/util/MemoryLeakUtil.java
@@ -14,10 +14,12 @@
 package org.openmrs.util;
 
 import java.lang.reflect.Field;
+import java.util.Map;
 import java.util.Timer;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.hibernate.impl.SessionFactoryObjectFactory;
 
 import sun.net.www.http.HttpClient;
 import sun.net.www.http.KeepAliveCache;
@@ -81,4 +83,24 @@ public static void shutdownKeepAliveTimer() {
 			log.error(e.getMessage(), e);
 		}
 	}
+	
+	/**
+	 * Clears the hibernate session factories cached in the SessionFactoryObjectFactory
+	 */
+	public static void clearHibernateSessionFactories() {
+		try {
+			Field field = SessionFactoryObjectFactory.class.getDeclaredField("INSTANCES");
+			field.setAccessible(true);
+			Map instances = (Map) field.get(null);
+			instances.clear();
+			
+			field = SessionFactoryObjectFactory.class.getDeclaredField("NAMED_INSTANCES");
+			field.setAccessible(true);
+			Map namedInstances = (Map) field.get(null);
+			namedInstances.clear();
+		}
+		catch (Exception ex) {
+			log.error(ex.getMessage(), ex);
+		}
+	}
 }
diff --git a/api/src/main/java/org/openmrs/util/OpenmrsClassLoader.java b/api/src/main/java/org/openmrs/util/OpenmrsClassLoader.java
@@ -323,6 +323,8 @@ public static void destroyInstance() {
 				log.error(ex.getMessage(), ex);
 			}
 		}
+		
+		MemoryLeakUtil.clearHibernateSessionFactories();
 				
 		OpenmrsClassScanner.destroyInstance();
 		

Original file line number	Diff line number	Diff line change
`@@ -323,6 +323,8 @@ public static void destroyInstance() {`
`323`	`323`	`log.error(ex.getMessage(), ex);`
`324`	`324`	`}`
`325`	`325`	`}`
	`326`	`+`
	`327`	`+ MemoryLeakUtil.clearHibernateSessionFactories();`
`326`	`328`
`327`	`329`	`OpenmrsClassScanner.destroyInstance();`
`328`	`330`