lc-eo-changestream: Added change number tracking

lc-eo-changestream/src/main/java/lc/eo/changestream/ChangeStream.java

@@ -9,11 +9,24 @@ import java.io.Serializable;
 import java.util.HashSet;
 
 public class ChangeStream implements EditTracker {
+    private int changeNumber;
     private final HashSet<EO> objectsDirty = new HashSet<>();
     private final HashSet<EOLoop> loopsDirty = new HashSet<>();
     private final HashSet<EO> objectsRemoved = new HashSet<>();
     private final HashSet<EO> objectsAdded = new HashSet<>();
 
+    public void commit() {
+        objectsDirty.clear();
+        loopsDirty.clear();
+        objectsRemoved.clear();
+        objectsAdded.clear();
+        changeNumber++;
+    }
+
+    public int getChangeNumber() {
+        return changeNumber;
+    }
+
     @Override
     public void attributeUpdate(EO eo, String key, Serializable oldValue, Serializable newValue, EOListener listener) {
         if (objectsAdded.contains(eo)) return;

lc-eo-changestream/src/test/java/lc/eo/changestream/ChangeStreamTest.java

@@ -15,4 +15,14 @@ public class ChangeStreamTest {
         assertEquals(0, cs.getObjectsDirty().size());
         assertEquals(1, cs.getObjectsAdded().size());
     }
+
+    @Test
+    public void testChangeNumber() {
+        ChangeStream cs = new ChangeStream();
+        EO base = new EO();
+        base.setEditTracker(cs);
+        assertEquals(0, cs.getChangeNumber());
+        cs.commit();
+        assertEquals(1, cs.getChangeNumber());
+    }
 }