Change 'policy-core' to support app persistence

This includes the following:

1) A new hook method 'newPolicySession(PolicySession)' that is called after
   the session has been created and initialized

2) Support for "adjunct" objects in 'PolicySession'

3) Added 'try/catch' blocks around feature method invocations

4) Added 'default' methods to interface 'PolicySessionFeatureAPI'

5) Removed 'PolicySessionFeatureAPI.isPersistenceEnabled()'

Conflicts:

	policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySessionFeatureAPI.java

Change-Id: Ibc6d9eeacb6118d617e6c5ac53f6cef4c6ee1417
Signed-off-by: Ralph Straubs <rs8887@att.com>

3 files changed, 133 insertions, 23 deletions

diff --git a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicyContainer.java b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicyContainer.java
index d47ed617..fca30e00 100644
--- a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicyContainer.java
+++ b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicyContainer.java
@@ -280,11 +280,20 @@ public class PolicyContainer implements Startable
 
 			// loop through all of the features, and give each one
 			// a chance to create the 'KieSession'
-			for (PolicySessionFeatureAPI feature : PolicySessionFeatureAPI.impl.getList())
+			for (PolicySessionFeatureAPI feature :
+				   PolicySessionFeatureAPI.impl.getList())
 			  {
-				if ((kieSession = feature.activatePolicySession
-					 (this, name, kieBaseName)) != null)
-				  break;
+				try
+				  {
+					if ((kieSession = feature.activatePolicySession
+						 (this, name, kieBaseName)) != null)
+					  break;
+				  }
+				catch (Exception e)
+				  {
+					logger.error("ERROR: Feature API: "
+								 + feature.getClass().getName(), e);
+				  }
 			  }
 
 			// if none of the features created the session, create one now
@@ -299,6 +308,21 @@ public class PolicyContainer implements Startable
 				// a PolicySession
 				session = new PolicySession(name, this, kieSession);
 				sessions.put(name, session);
+
+				// notify features
+				for (PolicySessionFeatureAPI feature :
+					   PolicySessionFeatureAPI.impl.getList())
+				  {
+					try
+					  {
+						feature.newPolicySession(session);
+					  }
+					catch (Exception e)
+					  {
+						logger.error("ERROR: Feature API: "
+									 + feature.getClass().getName(), e);
+					  }
+				  }
 				logger.info("activatePolicySession:new session was added in sessions with name " + name);
 			  }
 		  }
@@ -374,6 +398,21 @@ public class PolicyContainer implements Startable
 		PolicySession policySession =
 		  new PolicySession(name, this, kieSession);
 		sessions.put(name, policySession);
+
+		// notify features
+		for (PolicySessionFeatureAPI feature :
+			   PolicySessionFeatureAPI.impl.getList())
+		  {
+			try
+			  {
+				feature.newPolicySession(policySession);
+			  }
+			catch (Exception e)
+			  {
+				logger.error("ERROR: Feature API: "
+							 + feature.getClass().getName(), e);
+			  }
+		  }
 		return(policySession);
 	  }
   }
@@ -590,9 +629,18 @@ public class PolicyContainer implements Startable
 			session.getKieSession().dispose();
 
 			// notify features
-			for (PolicySessionFeatureAPI feature : PolicySessionFeatureAPI.impl.getList())
+			for (PolicySessionFeatureAPI feature :
+				   PolicySessionFeatureAPI.impl.getList())
 			  {
-				feature.disposeKieSession(session);
+				try
+				  {
+					feature.disposeKieSession(session);
+				  }
+				catch (Exception e)
+				  {
+					logger.error("ERROR: Feature API: "
+								 + feature.getClass().getName(), e);
+				  }
 			  }
 		  }
 		isStarted = false;
@@ -657,9 +705,18 @@ public class PolicyContainer implements Startable
 		session.getKieSession().destroy();
 
 		// notify features
-		for (PolicySessionFeatureAPI feature : PolicySessionFeatureAPI.impl.getList())
+		for (PolicySessionFeatureAPI feature :
+			   PolicySessionFeatureAPI.impl.getList())
 		  {
-			feature.destroyKieSession(session);
+			try
+			  {
+				feature.destroyKieSession(session);
+			  }
+			catch (Exception e)
+			  {
+				logger.error("ERROR: Feature API: "
+							 + feature.getClass().getName(), e);
+			  }
 		  }
 	  }
 	isStarted = false;
@@ -750,9 +807,18 @@ public class PolicyContainer implements Startable
 	logger.info("initlogger returned");
 
 	// invoke 'globalInit' on all of the features
-	for (PolicySessionFeatureAPI feature : PolicySessionFeatureAPI.impl.getList())
+	for (PolicySessionFeatureAPI feature :
+		   PolicySessionFeatureAPI.impl.getList())
 	  {
-		feature.globalInit(args, configDir);
+		try
+		  {
+			feature.globalInit(args, configDir);
+		  }
+		catch (Exception e)
+		  {
+			logger.error("ERROR: Feature API: "
+						 + feature.getClass().getName(), e);
+		  }
 	  }
   }
 
diff --git a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySession.java b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySession.java
index 2149735a..ae9dbc45 100644
--- a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySession.java
+++ b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySession.java
@@ -20,6 +20,8 @@
 
 package org.openecomp.policy.drools.core;
 
+import java.util.concurrent.ConcurrentHashMap;
+
 import org.kie.api.event.rule.AfterMatchFiredEvent;
 import org.kie.api.event.rule.AgendaEventListener;
 import org.kie.api.event.rule.AgendaGroupPoppedEvent;
@@ -58,6 +60,10 @@ public class PolicySession
   // 'PolicySession' instances in addition to this one
   private PolicyContainer container;
 
+  // maps feature objects to per-PolicyContainer data
+  private ConcurrentHashMap<Object, Object> adjuncts =
+	new ConcurrentHashMap<Object, Object>();
+
   // associated 'KieSession' instance
   private KieSession kieSession;
 
@@ -223,6 +229,41 @@ public class PolicySession
   {
 	return(policySession.get());
   }
+	
+  /**
+   * Fetch the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @return a feature-specific object associated with the key, or 'null'
+   *	if it is not found.
+   */
+  public Object getAdjunct(Object object)
+  {
+	return(adjuncts.get(object));
+  }
+
+  /**
+   * Store the adjunct object associated with a given feature
+   *
+   * @param object this is typically the singleton feature object that is
+   *	used as a key, but it might also be useful to use nested objects
+   *	within the feature as keys.
+   * @param value a feature-specific object associated with the key, or 'null'
+   *	if the feature-specific object should be removed
+   */
+  public void setAdjunct(Object object, Object value)
+  {
+	if (value == null)
+	  {
+		adjuncts.remove(object);
+	  }
+	else
+	  {
+		adjuncts.put(object, value);
+	  }
+  }
 
   /***********************************/
   /* 'AgendaEventListener' interface */
diff --git a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySessionFeatureAPI.java b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySessionFeatureAPI.java
index d5057696..da828db3 100644
--- a/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySessionFeatureAPI.java
+++ b/policy-core/src/main/java/org/openecomp/policy/drools/core/PolicySessionFeatureAPI.java
@@ -48,7 +48,7 @@ public interface PolicySessionFeatureAPI extends OrderedService
    * @param args standard 'main' arguments, which are currently ignored
    * @param configDir the relative directory containing configuration files
    */
-  public void globalInit(String args[], String configDir);
+  default public void globalInit(String args[], String configDir) {}
 
   /**
    * This method is used to create a 'KieSession' as part of a
@@ -65,30 +65,33 @@ public interface PolicySessionFeatureAPI extends OrderedService
    *	(this depends on the capabilities and state of the object implementing
    *	this interface)
    */
-  public KieSession activatePolicySession
-	(PolicyContainer policyContainer, String name, String kieBaseName);
+  default public KieSession activatePolicySession
+	(PolicyContainer policyContainer, String name, String kieBaseName)
+  {
+	return(null);
+  }
 
   /**
-   * This method is called after 'KieSession.dispose()' is called
+   * This method is called after a new 'PolicySession' has been initialized,
+   * and linked to the 'PolicyContainer'.
    *
-   * @param policySession the 'PolicySession' object that wrapped the
-   *	'KieSession'
+   * @param policySession the new 'PolicySession' instance
    */
-  public void disposeKieSession(PolicySession policySession);
+  default public void newPolicySession(PolicySession policySession) {}
 
   /**
-   * This method is called after 'KieSession.destroy()' is called
+   * This method is called after 'KieSession.dispose()' is called
    *
    * @param policySession the 'PolicySession' object that wrapped the
    *	'KieSession'
    */
-  public void destroyKieSession(PolicySession policySession);
+  default public void disposeKieSession(PolicySession policySession) {}
 
   /**
-   * NOTE: this method is probably temporary
+   * This method is called after 'KieSession.destroy()' is called
    *
-   * @return 'true' if persistence is enabled, and 'false' if not, or if
-   *	this feature is not related to persistence.
+   * @param policySession the 'PolicySession' object that wrapped the
+   *	'KieSession'
    */
-  public boolean isPersistenceEnabled();
+  default public void destroyKieSession(PolicySession policySession) {}
 }