killbill-memoizeit

diff --git a/entitlement/src/main/java/org/killbill/billing/entitlement/api/DefaultEntitlement.java b/entitlement/src/main/java/org/killbill/billing/entitlement/api/DefaultEntitlement.java
index 970e1cd..6a99e3b 100644
--- a/entitlement/src/main/java/org/killbill/billing/entitlement/api/DefaultEntitlement.java
+++ b/entitlement/src/main/java/org/killbill/billing/entitlement/api/DefaultEntitlement.java
@@ -642,7 +642,9 @@ public class DefaultEntitlement extends EntityBase implements Entitlement {
         final WithEntitlementPlugin<Entitlement> changePlanWithPlugin = new WithEntitlementPlugin<Entitlement>() {
             @Override
             public Entitlement doCall(final EntitlementApi entitlementApi, final EntitlementContext updatedPluginContext) throws EntitlementApiException {
-                if (!eventsStream.isEntitlementActive()) {
+
+                if ((effectiveDate == null && !eventsStream.isEntitlementActive()) ||
+                        (effectiveDate != null && effectiveDate.compareTo(eventsStream.getEntitlementEffectiveStartDate()) < 0)) {
                     throw new EntitlementApiException(ErrorCode.SUB_CHANGE_NON_ACTIVE, getId(), getState());
                 }
 
@@ -715,7 +717,9 @@ public class DefaultEntitlement extends EntityBase implements Entitlement {
         final WithEntitlementPlugin<Entitlement> changePlanWithPlugin = new WithEntitlementPlugin<Entitlement>() {
             @Override
             public Entitlement doCall(final EntitlementApi entitlementApi, final EntitlementContext updatedPluginContext) throws EntitlementApiException {
-                if (!eventsStream.isEntitlementActive()) {
+
+                if ((entitlementEffectiveDate == null && !eventsStream.isEntitlementActive()) ||
+                        (entitlementEffectiveDate != null && entitlementEffectiveDate.compareTo(eventsStream.getEntitlementEffectiveStartDate()) < 0)) {
                     throw new EntitlementApiException(ErrorCode.SUB_CHANGE_NON_ACTIVE, getId(), getState());
                 }
 

diff --git a/entitlement/src/test/java/org/killbill/billing/entitlement/api/TestDefaultEntitlement.java b/entitlement/src/test/java/org/killbill/billing/entitlement/api/TestDefaultEntitlement.java
index 692995f..7d29cb7 100644
--- a/entitlement/src/test/java/org/killbill/billing/entitlement/api/TestDefaultEntitlement.java
+++ b/entitlement/src/test/java/org/killbill/billing/entitlement/api/TestDefaultEntitlement.java
@@ -282,7 +282,7 @@ public class TestDefaultEntitlement extends EntitlementTestSuiteWithEmbeddedDB {
     }
 
     @Test(groups = "slow")
-    public void testEntitlementStartedInFuture() throws AccountApiException, EntitlementApiException {
+    public void testEntitlementChangePlanOnPendingEntitlement() throws AccountApiException, EntitlementApiException {
         final LocalDate initialDate = new LocalDate(2013, 8, 7);
         clock.setDay(initialDate);
 
@@ -298,12 +298,37 @@ public class TestDefaultEntitlement extends EntitlementTestSuiteWithEmbeddedDB {
         assertListenerStatus();
         assertEquals(entitlement.getState(), EntitlementState.PENDING);
 
-        testListener.pushExpectedEvents(NextEvent.CREATE, NextEvent.BLOCK);
+        final PlanPhaseSpecifier spec2 = new PlanPhaseSpecifier("pistol-monthly", null);
+        try {
+            entitlement.changePlan(spec2, ImmutableList.<PlanPhasePriceOverride>of(), ImmutableList.<PluginProperty>of(), callContext);
+            Assert.fail("Changing plan immediately prior the subscription is active is not allowed");
+        } catch (EntitlementApiException e) {
+            Assert.assertEquals(e.getCode(), ErrorCode.SUB_CHANGE_NON_ACTIVE.getCode());
+        }
+
+        try {
+            entitlement.changePlanWithDate(spec2, ImmutableList.<PlanPhasePriceOverride>of(), null, ImmutableList.<PluginProperty>of(), callContext);
+            Assert.fail("Changing plan immediately prior the subscription is active is not allowed");
+        } catch (EntitlementApiException e) {
+            Assert.assertEquals(e.getCode(), ErrorCode.SUB_CHANGE_NON_ACTIVE.getCode());
+        }
+
+        try {
+            entitlement.changePlanWithDate(spec2, ImmutableList.<PlanPhasePriceOverride>of(), startDate.minusDays(1), ImmutableList.<PluginProperty>of(), callContext);
+            Assert.fail("Changing plan immediately prior the subscription is active is not allowed");
+        } catch (EntitlementApiException e) {
+            Assert.assertEquals(e.getCode(), ErrorCode.SUB_CHANGE_NON_ACTIVE.getCode());
+        }
+
+        entitlement.changePlanWithDate(spec2, ImmutableList.<PlanPhasePriceOverride>of(), startDate, ImmutableList.<PluginProperty>of(), callContext);
+
+        testListener.pushExpectedEvents(NextEvent.CREATE, NextEvent.CHANGE, NextEvent.BLOCK);
         clock.addDays(10);
         assertListenerStatus();
 
         final Entitlement entitlement1 = entitlementApi.getEntitlementForId(entitlement.getId(), callContext);
         assertEquals(entitlement1.getState(), EntitlementState.ACTIVE);
+        assertEquals(entitlement1.getLastActiveProduct().getName(), "Pistol");
 
     }
 }