Start of support for soft-delete, metadata extension properties and

surrogate column enum. For #180

src/main/java/org/datanucleus/metadata/MetaData.java

@@ -74,6 +74,12 @@ public class MetaData implements Serializable
     /** Class : when using multitenancy, defines the jdbc-type used for the mutitenancy discriminator column. */
     public static final String EXTENSION_CLASS_MULTITENANCY_JDBC_TYPE = "multitenancy-jdbc-type";
 
+    /** Class : when the class will use soft deletion (deletion flag column) rather than actually deleting objects. */
+    public static final String EXTENSION_CLASS_SOFTDELETE = "softdelete";
+
+    /** Class : when the class will use soft deletion, specifies the column name to use. */
+    public static final String EXTENSION_CLASS_SOFTDELETE_COLUMN_NAME = "softdelete-column-name";
+
     /** Class : define the name of a field that will store the version of this class. */
     public static final String EXTENSION_CLASS_VERSION_FIELD_NAME = "field-name";
 

src/main/java/org/datanucleus/store/schema/table/CompleteClassTable.java

@@ -85,6 +85,8 @@ public class CompleteClassTable implements Table
 
     Column multitenancyColumn;
 
+    Column softDeleteColumn;
+
     // TODO Support create-timestamp surrogate
     // TODO Support update-timestamp surrogate
     /** Map of member-column mapping, keyed by the metadata for the member. */
@@ -547,6 +549,8 @@ else if (mmd.hasMap())
             this.multitenancyColumn = col;
         }
 
+        // TODO Add soft delete column when required
+
         // Reorder all columns to respect column positioning information. Note this assumes the user has provided complete information
         List<Column> unorderedCols = new ArrayList();
         Column[] cols = new Column[columns.size()];
@@ -1149,6 +1153,10 @@ else if (colType == SurrogateColumnType.UPDATE_TIMESTAMP)
         {
             // TODO Support this
         }
+        else if (colType == SurrogateColumnType.SOFTDELETE)
+        {
+            return softDeleteColumn;
+        }
         return null;
     }
 

src/main/java/org/datanucleus/store/schema/table/SurrogateColumnType.java

@@ -27,5 +27,6 @@ public enum SurrogateColumnType
     DISCRIMINATOR,
     MULTITENANCY,
     CREATE_TIMESTAMP,
-    UPDATE_TIMESTAMP
+    UPDATE_TIMESTAMP,
+    SOFTDELETE
 }