1 files changed, 22 insertions, 10 deletions

diff --git a/src/de/lmu/ifi/dbs/elki/database/relation/Relation.java b/src/de/lmu/ifi/dbs/elki/database/relation/Relation.java
index ebe1be3c..4969ad50 100644
--- a/src/de/lmu/ifi/dbs/elki/database/relation/Relation.java
+++ b/src/de/lmu/ifi/dbs/elki/database/relation/Relation.java
@@ -25,17 +25,19 @@ package de.lmu.ifi.dbs.elki.database.relation;
 
 import de.lmu.ifi.dbs.elki.data.type.SimpleTypeInformation;
 import de.lmu.ifi.dbs.elki.database.Database;
-import de.lmu.ifi.dbs.elki.database.ids.DBID;
+import de.lmu.ifi.dbs.elki.database.ids.DBIDIter;
+import de.lmu.ifi.dbs.elki.database.ids.DBIDRef;
 import de.lmu.ifi.dbs.elki.database.ids.DBIDs;
 import de.lmu.ifi.dbs.elki.database.query.DatabaseQuery;
 import de.lmu.ifi.dbs.elki.result.HierarchicalResult;
-import de.lmu.ifi.dbs.elki.utilities.iterator.IterableIterator;
 
 /**
  * An object representation from a database
  * 
  * @author Erich Schubert
- *
+ * 
+ * @apiviz.uses DBIDRef
+ * 
  * @param <O> Object type
  */
 public interface Relation<O> extends DatabaseQuery, HierarchicalResult {
@@ -47,15 +49,15 @@ public interface Relation<O> extends DatabaseQuery, HierarchicalResult {
    * @return Database
    */
   public Database getDatabase();
-  
+
   /**
    * Get the representation of an object.
    * 
    * @param id Object ID
    * @return object instance
    */
-  public O get(DBID id);
-  
+  public O get(DBIDRef id);
+
   /**
    * Set an object representation.
    * 
@@ -63,14 +65,14 @@ public interface Relation<O> extends DatabaseQuery, HierarchicalResult {
    * @param val Value
    */
   // TODO: remove / move to a writable API?
-  public void set(DBID id, O val);
+  public void set(DBIDRef id, O val);
 
   /**
    * Delete an objects values.
    * 
    * @param id ID to delete
    */
-  public void delete(DBID id);
+  public void delete(DBIDRef id);
 
   /**
    * Get the data type of this representation
@@ -78,7 +80,7 @@ public interface Relation<O> extends DatabaseQuery, HierarchicalResult {
    * @return Data type
    */
   public SimpleTypeInformation<O> getDataTypeInformation();
-  
+
   /**
    * Get the IDs the query is defined for.
    * 
@@ -89,9 +91,19 @@ public interface Relation<O> extends DatabaseQuery, HierarchicalResult {
   /**
    * Get an iterator access to the DBIDs.
    * 
+   * To iterate over all IDs, use the following code fragment:
+   * 
+   * <pre>
+   * {@code
+   * for(DBIDIter iter = relation.iterDBIDs(); iter.valid(); iter.advance()) {
+   *    DBID id = iter.getDBID();
+   * }
+   * }
+   * </pre>
+   * 
    * @return iterator for the DBIDs.
    */
-  public IterableIterator<DBID> iterDBIDs();
+  public DBIDIter iterDBIDs();
 
   /**
    * Get the number of DBIDs.