Qualify index names with their table name.

src/main/java/net/helenus/core/SchemaUtil.java

@@ -337,7 +337,7 @@ public final class SchemaUtil {
 
   public static SchemaStatement createIndex(HelenusProperty prop) {
     if (prop.caseSensitiveIndex()) {
-      return SchemaBuilder.createIndex(prop.getIndexName().get().toCql())
+      return SchemaBuilder.createIndex(indexName(prop))
           .ifNotExists()
           .onTable(prop.getEntity().getName().toCql())
           .andColumn(prop.getColumnName().toCql());
@@ -406,7 +406,7 @@ public final class SchemaUtil {
   }
 
   public static SchemaStatement dropIndex(HelenusProperty prop) {
-    return SchemaBuilder.dropIndex(prop.getIndexName().get().toCql()).ifExists();
+    return SchemaBuilder.dropIndex(indexName(prop)).ifExists();
   }
 
   private static SchemaBuilder.Direction mapDirection(OrderingDirection o) {
@@ -465,4 +465,9 @@ public final class SchemaUtil {
     }
     return null;
   }
+
+  private static String indexName(HelenusProperty prop) {
+      return prop.getEntity().getName().toCql() + "_" + prop.getIndexName().get().toCql();
+  }
+
 }

src/main/java/net/helenus/core/reflect/Entity.java

@@ -20,20 +20,53 @@ import net.helenus.core.Getter;
 public interface Entity {
   String WRITTEN_AT_METHOD = "writtenAt";
   String TTL_OF_METHOD = "ttlOf";
+  String TOKEN_OF_METHOD = "tokenOf";
 
+    /**
+     * The write time for the property in question referenced by the getter.
+     *
+     * @param getter the property getter
+     * @return the timestamp associated with the property identified by the getter
+     */
   default Long writtenAt(Getter getter) {
     return 0L;
   }
 
+    /**
+     * The write time for the property in question referenced by the property name.
+     *
+     * @param prop the name of a property in this entity
+     * @return the timestamp associated with the property identified by the property name if it exists
+     */
   default Long writtenAt(String prop) {
     return 0L;
   };
 
+    /**
+     * The time-to-live for the property in question referenced by the getter.
+     *
+     * @param getter the property getter
+     * @return the time-to-live in seconds associated with the property identified by the getter
+     */
   default Integer ttlOf(Getter getter) {
     return 0;
   };
 
+    /**
+     * The time-to-live for the property in question referenced by the property name.
+     *
+     * @param prop the name of a property in this entity
+     * @return the time-to-live in seconds associated with the property identified by the property name if it exists
+     */
   default Integer ttlOf(String prop) {
     return 0;
   };
+
+    /**
+     * The token (partition identifier) for this entity which can change over time if
+     * the cluster grows or shrinks but should be stable otherwise.
+     *
+     * @return the token for the entity
+     */
+  default Long tokenOf() { return 0L; }
 }

src/main/java/net/helenus/core/reflect/MapperInvocationHandler.java

@@ -147,6 +147,14 @@ public class MapperInvocationHandler<E> implements InvocationHandler, Serializab
       return 0L;
     }
 
+    if (Entity.TOKEN_OF_METHOD.equals(methodName) && method.getParameterCount() == 0) {
+        Long v = (Long) src.get("");
+        if (v != null) {
+            return v;
+        }
+        return 0L;
+    }
+
     if (Entity.TTL_OF_METHOD.equals(methodName) && method.getParameterCount() == 1) {
       final String key;
       if (args[0] instanceof String) {