sonar issue - drools apps

- elevate the visibility of readResolve
- test case without assertions

Issue-ID: POLICY-2616
Change-Id: Ifde4b8c5e1281f8625a1203858fbe0467defe353
Signed-off-by: Taka Cho <takamune.cho@att.com>
diff --git a/controlloop/m2/base/src/test/java/org/onap/policy/m2/base/TransactionTest.java b/controlloop/m2/base/src/test/java/org/onap/policy/m2/base/TransactionTest.java
index c5fa6be..9158a6f 100644
--- a/controlloop/m2/base/src/test/java/org/onap/policy/m2/base/TransactionTest.java
+++ b/controlloop/m2/base/src/test/java/org/onap/policy/m2/base/TransactionTest.java
@@ -20,6 +20,7 @@
 
 package org.onap.policy.m2.base;
 
+import static org.assertj.core.api.Assertions.assertThatCode;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -320,6 +321,7 @@
     public void testSetNotificationMessage() {
         Transaction transaction = new Transaction(mockWorkingMemory, CL_NAME, UUID.randomUUID(), createControlLoop());
         transaction.setNotificationMessage("test");
+        assertEquals("test", transaction.getNotificationMessage());
     }
 
     @Test
@@ -345,6 +347,7 @@
         GuardAdjunct adjunct2 = new GuardAdjunct();
         transaction.putAdjunct(adjunct2);
         transaction.cleanup();
+        assertThatCode(() -> transaction.cleanup()).doesNotThrowAnyException();
     }
 
     private VirtualControlLoopEvent createControlLoopEvent(UUID requestId, String closedLoopControlName,
diff --git a/controlloop/m2/util/src/main/java/org/onap/policy/util/DroolsSessionCommonSerializable.java b/controlloop/m2/util/src/main/java/org/onap/policy/util/DroolsSessionCommonSerializable.java
index c76a8c2..0d60b25 100644
--- a/controlloop/m2/util/src/main/java/org/onap/policy/util/DroolsSessionCommonSerializable.java
+++ b/controlloop/m2/util/src/main/java/org/onap/policy/util/DroolsSessionCommonSerializable.java
@@ -78,7 +78,7 @@
      * @return the local named object (if available), or the deserialized
      *     object
      */
-    private Object readResolve() throws ObjectStreamException {
+    protected Object readResolve() throws ObjectStreamException {
         Adjunct adjunct = getAdjunct();
         Object replacementObject;