Using DataRetrieverLevel(DTO) instead of a simple int everywhere

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/client/StringMessages.properties

@@ -1342,4 +1342,4 @@ cantDisplayDataOfType=Can''t display data of type {0}
 shownDecimals=Shown Decimals
 openFullscreenView=Open fullscreen view
 closeFullscreenView=Close fullscreen view
-analyse=Analyze
+analyze=Analyze

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/client/StringMessages_de.properties

@@ -1331,4 +1331,4 @@ cantDisplayDataOfType=Daten des Typs {0} können nicht dargestellt werden
 shownDecimals=Angezeigte Nachkommastellen
 openFullscreenView=Vollbildansicht öffnen
 closeFullscreenView=Vollbildansicht schließen
-analyse=Untersuche
+analyze=Untersuche

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/client/StringMessages_ru.properties

@@ -1281,4 +1281,4 @@ cantDisplayDataOfType=Can''t display data of type {0}
 shownDecimals=Shown Decimals
 openFullscreenView=Open fullscreen view
 closeFullscreenView=Close fullscreen view
-analyse=Analyze
+analyze=Analyze

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/DataMiningService.java

@@ -34,8 +34,8 @@ public interface DataMiningService extends RemoteService {
     ArrayList<DataRetrieverChainDefinitionDTO> getDataRetrieverChainDefinitions(String localeName);
     ArrayList<DataRetrieverChainDefinitionDTO> getDataRetrieverChainDefinitionsFor(FunctionDTO statisticToCalculate, String localeInfoName);
 
-    QueryResultDTO<HashSet<Object>> getDimensionValuesFor(DataMiningSession session, DataRetrieverChainDefinitionDTO dataRetrieverChainDefinitionDTO, int retrieverLevel,
-            HashSet<FunctionDTO> dimensionDTOs, HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO, String localeInfoName);
+    QueryResultDTO<HashSet<Object>> getDimensionValuesFor(DataMiningSession session, DataRetrieverChainDefinitionDTO dataRetrieverChainDefinitionDTO, DataRetrieverLevelDTO retrieverLevel,
+            HashSet<FunctionDTO> dimensionDTOs, HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO, String localeInfoName);
     
     <ResultType> QueryResultDTO<ResultType> runQuery(DataMiningSession session, StatisticQueryDefinitionDTO queryDefinition);
 

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/DataMiningServiceAsync.java

@@ -38,8 +38,8 @@ public interface DataMiningServiceAsync {
     void getDataRetrieverChainDefinitionsFor(FunctionDTO statisticToCalculate, String localeInfoName,
             AsyncCallback<ArrayList<DataRetrieverChainDefinitionDTO>> callback);
 
-    void getDimensionValuesFor(DataMiningSession session, DataRetrieverChainDefinitionDTO dataRetrieverChainDefinitionDTO, int retrieverLevel,
-            HashSet<FunctionDTO> dimensionDTOs, HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO,
+    void getDimensionValuesFor(DataMiningSession session, DataRetrieverChainDefinitionDTO dataRetrieverChainDefinitionDTO, DataRetrieverLevelDTO retrieverLevel,
+            HashSet<FunctionDTO> dimensionDTOs, HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO,
             String localeInfoName, AsyncCallback<QueryResultDTO<HashSet<Object>>> callback);
 
     <ResultType> void runQuery(DataMiningSession session, StatisticQueryDefinitionDTO queryDefinition, AsyncCallback<QueryResultDTO<ResultType>> callback);

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/FilterSelectionProvider.java

@@ -5,13 +5,14 @@ import java.util.HashMap;
 import java.util.HashSet;
 
 import com.sap.sse.datamining.shared.dto.StatisticQueryDefinitionDTO;
+import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
 
 public interface FilterSelectionProvider extends DataMiningComponentProvider, DataRetrieverChainDefinitionChangedListener {
 
     public void addSelectionChangedListener(FilterSelectionChangedListener listener);
 
-    public HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getSelection();
+    public HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getSelection();
 
     public void applySelection(StatisticQueryDefinitionDTO queryDefinition);
 

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/presentation/PlainFilterSelectionPresenter.java

@@ -65,13 +65,12 @@ public class PlainFilterSelectionPresenter implements FilterSelectionPresenter,
     public void selectionChanged() {
         presentationPanel.clear();
         
-        Map<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> selection = filterSelectionProvider.getSelection();
-        List<Integer> sortedLevels = new ArrayList<>(selection.keySet());
+        Map<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> selection = filterSelectionProvider.getSelection();
+        List<DataRetrieverLevelDTO> sortedLevels = new ArrayList<>(selection.keySet());
         Collections.sort(sortedLevels);
         boolean first = true;
-        for (Integer levelIndex : sortedLevels) {
-            Map<FunctionDTO, HashSet<? extends Serializable>> levelSelection = selection.get(levelIndex);
-            DataRetrieverLevelDTO retrieverLevel = retrieverChain.getRetrieverLevel(levelIndex);
+        for (DataRetrieverLevelDTO retrieverLevel : sortedLevels) {
+            Map<FunctionDTO, HashSet<? extends Serializable>> levelSelection = selection.get(retrieverLevel);
             RetrieverLevelFilterSelectionPresenter levelSelectionPresenter = new RetrieverLevelFilterSelectionPresenter(retrieverLevel, levelSelection);
             if (!first) {
                 levelSelectionPresenter.getEntryWidget().getElement().getStyle().setMarginTop(5, Unit.PX);

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/selection/BufferingQueryDefinitionProviderWithControls.java

@@ -36,6 +36,7 @@ import com.sap.sse.datamining.shared.DataMiningSession;
 import com.sap.sse.datamining.shared.dto.StatisticQueryDefinitionDTO;
 import com.sap.sse.datamining.shared.impl.dto.AggregationProcessorDefinitionDTO;
 import com.sap.sse.datamining.shared.impl.dto.DataRetrieverChainDefinitionDTO;
+import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
 import com.sap.sse.datamining.shared.impl.dto.ModifiableStatisticQueryDefinitionDTO;
 import com.sap.sse.gwt.client.ErrorReporter;
@@ -178,7 +179,7 @@ public class BufferingQueryDefinitionProviderWithControls extends AbstractQueryD
             queryDTO.appendDimensionToGroupBy(dimension);
         }
         
-        for (Entry<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionEntry : filterSelectionProvider.getSelection().entrySet()) {
+        for (Entry<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionEntry : filterSelectionProvider.getSelection().entrySet()) {
             queryDTO.setFilterSelectionFor(filterSelectionEntry.getKey(), filterSelectionEntry.getValue());
         }
         

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/selection/filter/DimensionFilterSelectionProvider.java

@@ -34,6 +34,7 @@ import com.sap.sailing.gwt.ui.datamining.execution.SimpleManagedDataMiningQuerie
 import com.sap.sse.datamining.shared.DataMiningSession;
 import com.sap.sse.datamining.shared.GroupKey;
 import com.sap.sse.datamining.shared.impl.GenericGroupKey;
+import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
 import com.sap.sse.datamining.shared.impl.dto.QueryResultDTO;
 import com.sap.sse.gwt.client.ErrorReporter;
@@ -158,15 +159,15 @@ class DimensionFilterSelectionProvider {
         final FunctionDTO dimension = getSelectedDimension();
         HashSet<FunctionDTO> dimensionDTOs = new HashSet<>();
         dimensionDTOs.add(dimension);
-        HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO = retrieverLevelSelectionProvider.getCompleteFilterSelection();
-        int retrieverLevel = retrieverLevelSelectionProvider.getRetrieverLevel();
+        HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO = retrieverLevelSelectionProvider.getCompleteFilterSelection();
+        DataRetrieverLevelDTO retrieverLevel = retrieverLevelSelectionProvider.getRetrieverLevel();
         if (filterSelectionDTO.containsKey(retrieverLevel)) {
             filterSelectionDTO.get(retrieverLevel).remove(dimension);
         }
         busyIndicator.setVisible(true);
         counter.increase();
         dataMiningService.getDimensionValuesFor(session, retrieverLevelSelectionProvider.getDataRetrieverChain(),
-                retrieverLevelSelectionProvider.getRetrieverLevel(), dimensionDTOs, filterSelectionDTO,
+                retrieverLevel, dimensionDTOs, filterSelectionDTO,
                 LocaleInfo.getCurrentLocale().getLocaleName(), new ManagedDataMiningQueryCallback<HashSet<Object>>(counter) {
                     @Override
                     protected void handleSuccess(QueryResultDTO<HashSet<Object>> result) {

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/selection/filter/ListRetrieverChainFilterSelectionProvider.java

@@ -177,15 +177,16 @@ public class ListRetrieverChainFilterSelectionProvider implements FilterSelectio
         }
     }
     
-    void updateFilterSelectionProviders(int beginningWithLevel, final FunctionDTO exceptForDimension) {
+    void updateFilterSelectionProviders(DataRetrieverLevelDTO beginningWithLevel, final FunctionDTO exceptForDimension) {
+        DataRetrieverLevelDTO currentLevel = beginningWithLevel;
         DataRetrieverLevelDTO retrieverLevelToUpdate = null;
-        for (int retrieverLevelIndex = beginningWithLevel; retrieverLevelIndex < retrieverChain.size(); retrieverLevelIndex++) {
-            DataRetrieverLevelDTO retrieverLevel = retrieverChain.getRetrieverLevel(retrieverLevelIndex);
-            if (selectionProvidersMappedByRetrievedDataType.containsKey(retrieverLevel)) {
-                retrieverLevelToUpdate = retrieverLevel;
+        do {
+            if (selectionProvidersMappedByRetrievedDataType.containsKey(currentLevel)) {
+                retrieverLevelToUpdate = currentLevel;
                 break;
             }
-        }
+            currentLevel = retrieverChain.getNextRetrieverLevel(currentLevel);
+        } while (currentLevel != null);
         
         if (retrieverLevelToUpdate != null) {
             selectionProvidersMappedByRetrievedDataType.get(retrieverLevelToUpdate).updateAvailableData(exceptForDimension);
@@ -201,8 +202,8 @@ public class ListRetrieverChainFilterSelectionProvider implements FilterSelectio
     }
 
     @Override
-    public HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getSelection() {
-        HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection = new HashMap<>();
+    public HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getSelection() {
+        HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection = new HashMap<>();
         for (RetrieverLevelFilterSelectionProvider selectionProvider : selectionProvidersMappedByRetrievedDataType.values()) {
             Map<FunctionDTO, HashSet<? extends Serializable>> levelFilterSelection = selectionProvider.getFilterSelection();
             if (!levelFilterSelection.isEmpty()) {
@@ -215,8 +216,8 @@ public class ListRetrieverChainFilterSelectionProvider implements FilterSelectio
     @Override
     public void applySelection(StatisticQueryDefinitionDTO queryDefinition) {
         for (RetrieverLevelFilterSelectionProvider selectionProvider : selectionProvidersMappedByRetrievedDataType.values()) {
-            Map<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection = queryDefinition.getFilterSelection();
-            int retrieverLevel = selectionProvider.getRetrieverLevel();
+            Map<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection = queryDefinition.getFilterSelection();
+            DataRetrieverLevelDTO retrieverLevel = selectionProvider.getRetrieverLevel();
             if (filterSelection.containsKey(retrieverLevel)) {
                 selectionProvider.applySelection(filterSelection.get(retrieverLevel));
             }

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/datamining/selection/filter/RetrieverLevelFilterSelectionProvider.java

@@ -19,7 +19,6 @@ import com.sap.sse.datamining.shared.DataMiningSession;
 import com.sap.sse.datamining.shared.impl.dto.DataRetrieverChainDefinitionDTO;
 import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
-import com.sap.sse.datamining.shared.impl.dto.LocalizedTypeDTO;
 import com.sap.sse.gwt.client.ErrorReporter;
 import com.sap.sse.gwt.client.shared.components.Component;
 import com.sap.sse.gwt.client.shared.components.SettingsDialogComponent;
@@ -142,7 +141,7 @@ public class RetrieverLevelFilterSelectionProvider implements Component<Abstract
             }
         } else {
             // Update for this level is completed. Continue with the next level.
-            retrieverChainSelectionProvider.updateFilterSelectionProviders(getRetrieverLevel() + 1, exceptForDimension);
+            retrieverChainSelectionProvider.updateFilterSelectionProviders(retrieverChain.getNextRetrieverLevel(getRetrieverLevel()), exceptForDimension);
         }
     }
 
@@ -150,7 +149,7 @@ public class RetrieverLevelFilterSelectionProvider implements Component<Abstract
         retrieverChainSelectionProvider.retrieverLevelFilterSelectionChanged(this, dimensionFilterSelectionProvider);
     }
 
-    HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getCompleteFilterSelection() {
+    HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getCompleteFilterSelection() {
         return retrieverChainSelectionProvider.getSelection();
     }
 
@@ -193,12 +192,8 @@ public class RetrieverLevelFilterSelectionProvider implements Component<Abstract
         return retrieverChain;
     }
     
-    public int getRetrieverLevel() {
-        return retrieverLevel.getLevel();
-    }
-    
-    public LocalizedTypeDTO getRetrievedDataType() {
-        return retrieverLevel.getRetrievedDataType();
+    public DataRetrieverLevelDTO getRetrieverLevel() {
+        return retrieverLevel;
     }
 
     @Override

java/com.sap.sailing.gwt.ui/src/main/java/com/sap/sailing/gwt/ui/server/DataMiningServiceImpl.java

@@ -187,11 +187,12 @@ public class DataMiningServiceImpl extends RemoteServiceServlet implements DataM
 
     @Override
     public QueryResultDTO<HashSet<Object>> getDimensionValuesFor(DataMiningSession session, DataRetrieverChainDefinitionDTO dataRetrieverChainDefinitionDTO,
-            int retrieverLevel, HashSet<FunctionDTO> dimensionDTOs, HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO, String localeInfoName) {
+            DataRetrieverLevelDTO retrieverLevelDTO, HashSet<FunctionDTO> dimensionDTOs, HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO, String localeInfoName) {
         DataMiningServer dataMiningServer = getDataMiningServer();
         DataRetrieverChainDefinition<RacingEventService, ?> retrieverChainDefinition = dataMiningServer.getDataRetrieverChainDefinition(dataRetrieverChainDefinitionDTO.getId());
+        DataRetrieverLevel<?, ?> retrieverLevel = retrieverChainDefinition.getDataRetrieverLevel(retrieverLevelDTO.getLevel());
         Iterable<Function<?>> dimensions = functionDTOsAsFunctions(dimensionDTOs);
-        Map<Integer, Map<Function<?>, Collection<?>>> filterSelection = filterSelectionDTOAsFilterSelection(filterSelectionDTO);
+        Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection = filterSelectionDTOAsFilterSelection(filterSelectionDTO, retrieverChainDefinition);
         Locale locale = ResourceBundleStringMessages.Util.getLocaleFor(localeInfoName);
         Query<HashSet<Object>> dimensionValuesQuery = dataMiningServer.createDimensionValuesQuery(retrieverChainDefinition, retrieverLevel, dimensions, filterSelection, locale);
         QueryResult<HashSet<Object>> result = dataMiningServer.runNewQueryAndAbortPreviousQueries(session, dimensionValuesQuery);
@@ -210,14 +211,16 @@ public class DataMiningServiceImpl extends RemoteServiceServlet implements DataM
         return functions;
     }
 
-    private Map<Integer, Map<Function<?>, Collection<?>>> filterSelectionDTOAsFilterSelection(
-            HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO) {
-        Map<Integer, Map<Function<?>, Collection<?>>> filterSelection = new HashMap<>();
-        for (Integer retrieverLevel : filterSelectionDTO.keySet()) {
-            HashMap<FunctionDTO, HashSet<? extends Serializable>> retrievalLevelSelection = filterSelectionDTO.get(retrieverLevel);
+    private Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelectionDTOAsFilterSelection(
+            HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelectionDTO,
+            DataRetrieverChainDefinition<?, ?> retrieverChainDefinition) {
+        Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection = new HashMap<>();
+        for (DataRetrieverLevelDTO retrieverLevelDTO : filterSelectionDTO.keySet()) {
+            HashMap<FunctionDTO, HashSet<? extends Serializable>> retrievalLevelSelection = filterSelectionDTO.get(retrieverLevelDTO);
             for (FunctionDTO dimensionDTO : retrievalLevelSelection.keySet()) {
                 if (!retrievalLevelSelection.get(dimensionDTO).isEmpty()) {
                     Function<?> function = getDataMiningServer().getFunctionForDTO(dimensionDTO);
+                    DataRetrieverLevel<?, ?> retrieverLevel = retrieverChainDefinition.getDataRetrieverLevel(retrieverLevelDTO.getLevel());
                     if (function != null) {
                         if (!filterSelection.containsKey(retrieverLevel)) {
                             filterSelection.put(retrieverLevel, new HashMap<Function<?>, Collection<?>>());

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/dto/StatisticQueryDefinitionDTO.java

@@ -4,9 +4,11 @@ import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Map;
 
 import com.sap.sse.datamining.shared.impl.dto.AggregationProcessorDefinitionDTO;
 import com.sap.sse.datamining.shared.impl.dto.DataRetrieverChainDefinitionDTO;
+import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
 
 public interface StatisticQueryDefinitionDTO extends Serializable {
@@ -14,7 +16,7 @@ public interface StatisticQueryDefinitionDTO extends Serializable {
     public String getLocaleInfoName();
     
     public DataRetrieverChainDefinitionDTO getDataRetrieverChainDefinition();
-    public HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getFilterSelection();
+    public Map<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getFilterSelection();
     public ArrayList<FunctionDTO> getDimensionsToGroupBy();
     public FunctionDTO getStatisticToCalculate();
     public AggregationProcessorDefinitionDTO getAggregatorDefinition();

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/impl/dto/DataRetrieverChainDefinitionDTO.java

@@ -47,27 +47,53 @@ public class DataRetrieverChainDefinitionDTO implements Serializable, Comparable
         return retrieverLevels;
     }
     
-    public int size() {
+    public int getLevelAmount() {
         return retrieverLevels.size();
     }
     
-    public DataRetrieverLevelDTO getRetrieverLevel(int retrieverLevel) {
-        return retrieverLevels.get(retrieverLevel);
+    /**
+     * @param levelIndex
+     * @return The retriever level for the given index or <code>null</code>, if the index is out of bounds.
+     */
+    public DataRetrieverLevelDTO getRetrieverLevel(int levelIndex) {
+        if (levelIndex < 0 || levelIndex >= getLevelAmount()) {
+            return null;
+        }
+        return retrieverLevels.get(levelIndex);
+    }
+    
+    /**
+     * @param retrieverLevel
+     * @return The retriever level after the given one or <code>null</code>, if the given one is the last one in the chain.
+     */
+    public DataRetrieverLevelDTO getNextRetrieverLevel(DataRetrieverLevelDTO retrieverLevel) {
+        return getRetrieverLevel(retrieverLevel.getLevel() + 1);
+    }
+    
+    /**
+     * @param retrieverLevel
+     * @return The retriever level before the given one or <code>null</code>, if the given one is the first one in the chain.
+     */
+    public DataRetrieverLevelDTO getPreviousRetrieverLevel(DataRetrieverLevelDTO retrieverLevel) {
+        return getRetrieverLevel(retrieverLevel.getLevel() - 1);
     }
 
     @Override
     public int compareTo(DataRetrieverChainDefinitionDTO d) {
         return this.getName().compareTo(d.getName());
     }
+    
+    @Override
+    public String toString() {
+        return getDataSourceTypeName() + " -> " + getRetrievedDataTypeName() +
+               "[ID: " + id + ", name: " + name + "]";
+    }
 
     @Override
     public int hashCode() {
         final int prime = 31;
         int result = 1;
-        result = prime * result + ((dataSourceTypeName == null) ? 0 : dataSourceTypeName.hashCode());
         result = prime * result + ((id == null) ? 0 : id.hashCode());
-        result = prime * result + ((name == null) ? 0 : name.hashCode());
-        result = prime * result + ((retrieverLevels == null) ? 0 : retrieverLevels.hashCode());
         return result;
     }
 
@@ -80,26 +106,11 @@ public class DataRetrieverChainDefinitionDTO implements Serializable, Comparable
         if (getClass() != obj.getClass())
             return false;
         DataRetrieverChainDefinitionDTO other = (DataRetrieverChainDefinitionDTO) obj;
-        if (dataSourceTypeName == null) {
-            if (other.dataSourceTypeName != null)
-                return false;
-        } else if (!dataSourceTypeName.equals(other.dataSourceTypeName))
-            return false;
         if (id == null) {
             if (other.id != null)
                 return false;
         } else if (!id.equals(other.id))
             return false;
-        if (name == null) {
-            if (other.name != null)
-                return false;
-        } else if (!name.equals(other.name))
-            return false;
-        if (retrieverLevels == null) {
-            if (other.retrieverLevels != null)
-                return false;
-        } else if (!retrieverLevels.equals(other.retrieverLevels))
-            return false;
         return true;
     }
     

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/impl/dto/DataRetrieverLevelDTO.java

@@ -2,7 +2,7 @@ package com.sap.sse.datamining.shared.impl.dto;
 
 import java.io.Serializable;
 
-public class DataRetrieverLevelDTO implements Serializable {
+public class DataRetrieverLevelDTO implements Serializable, Comparable<DataRetrieverLevelDTO> {
     private static final long serialVersionUID = 6911713148350359643L;
     
     private int retrieverLevel;
@@ -32,6 +32,11 @@ public class DataRetrieverLevelDTO implements Serializable {
     public LocalizedTypeDTO getRetrievedDataType() {
         return retrievedDataType;
     }
+    
+    @Override
+    public int compareTo(DataRetrieverLevelDTO otherRetrieverLevel) {
+        return Integer.compare(getLevel(), otherRetrieverLevel.getLevel());
+    }
 
     @Override
     public int hashCode() {

java/com.sap.sse.datamining.shared/src/com/sap/sse/datamining/shared/impl/dto/ModifiableStatisticQueryDefinitionDTO.java

@@ -15,7 +15,7 @@ public class ModifiableStatisticQueryDefinitionDTO implements StatisticQueryDefi
     private AggregationProcessorDefinitionDTO aggregatorDefinition;
     private ArrayList<FunctionDTO> dimensionsToGroupBy;
     private DataRetrieverChainDefinitionDTO dataRetrieverChainDefinition;
-    private HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection;
+    private HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> filterSelection;
     
     /**
      * <b>Constructor for the GWT-Serialization. Don't use this!</b>
@@ -32,7 +32,7 @@ public class ModifiableStatisticQueryDefinitionDTO implements StatisticQueryDefi
         this.dimensionsToGroupBy = new ArrayList<FunctionDTO>();
     }
     
-    public void setFilterSelectionFor(Integer retrieverLevel, HashMap<FunctionDTO, HashSet<? extends Serializable>> levelFilterSelection) {
+    public void setFilterSelectionFor(DataRetrieverLevelDTO retrieverLevel, HashMap<FunctionDTO, HashSet<? extends Serializable>> levelFilterSelection) {
         filterSelection.put(retrieverLevel, levelFilterSelection);
     }
     
@@ -51,7 +51,7 @@ public class ModifiableStatisticQueryDefinitionDTO implements StatisticQueryDefi
     }
 
     @Override
-    public HashMap<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getFilterSelection() {
+    public HashMap<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> getFilterSelection() {
         return filterSelection;
     }
 

java/com.sap.sse.datamining.test/src/com/sap/sse/datamining/impl/TestDimensionsValuesQuery.java

@@ -19,6 +19,7 @@ import com.sap.sse.datamining.components.DataRetrieverChainDefinition;
 import com.sap.sse.datamining.components.Processor;
 import com.sap.sse.datamining.data.QueryResult;
 import com.sap.sse.datamining.functions.Function;
+import com.sap.sse.datamining.impl.components.DataRetrieverLevel;
 import com.sap.sse.datamining.impl.components.SimpleDataRetrieverChainDefinition;
 import com.sap.sse.datamining.shared.GroupKey;
 import com.sap.sse.datamining.shared.impl.GenericGroupKey;
@@ -95,8 +96,8 @@ public class TestDimensionsValuesQuery {
         raceDimensions.add(dimensionRaceName);
         raceDimensions.add(dimensionBoatClassName);
         raceDimensions.add(dimensionYear);
-        Map<Integer, Map<Function<?>, Collection<?>>> filterSelection = new HashMap<>();
-        Query<HashSet<Object>> dimensionsValueQuery = server.createDimensionValuesQuery(dataRetrieverChainDefinition, 1 /*race*/, raceDimensions, filterSelection, locale);
+        Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection = new HashMap<>();
+        Query<HashSet<Object>> dimensionsValueQuery = server.createDimensionValuesQuery(dataRetrieverChainDefinition, dataRetrieverChainDefinition.getDataRetrieverLevel(/*race*/ 1), raceDimensions, filterSelection, locale);
         
         Map<GroupKey, HashSet<Object>> expectedRaceResultData = buildExpectedRaceResultData();
         QueryResult<HashSet<Object>> result = dimensionsValueQuery.run();
@@ -106,7 +107,7 @@ public class TestDimensionsValuesQuery {
         legDimensions.add(dimensionLegNumber);
         legDimensions.add(dimensionCompetitorName);
         legDimensions.add(dimensionCompetitorSailID);
-        dimensionsValueQuery = server.createDimensionValuesQuery(dataRetrieverChainDefinition, 2 /*leg*/, legDimensions, filterSelection, locale);
+        dimensionsValueQuery = server.createDimensionValuesQuery(dataRetrieverChainDefinition, dataRetrieverChainDefinition.getDataRetrieverLevel(/*leg*/ 2), legDimensions, filterSelection, locale);
 
         Map<GroupKey, HashSet<Object>> expectedLegResultData = buildExpectedLegResultData();
         result = dimensionsValueQuery.run();

java/com.sap.sse.datamining.test/src/com/sap/sse/datamining/impl/TestStatisticQuery.java

@@ -82,7 +82,7 @@ public class TestStatisticQuery {
         definition.addDimensionToGroupBy(functionFactory.createMethodWrappingFunction(getLengthMethod));
         
         Method getValueMethod = FunctionTestsUtil.getMethodFromClass(Number.class, "getValue");
-        definition.setFilterSelection(0, functionFactory.createMethodWrappingFunction(getValueMethod), Arrays.asList(10, 100, 1000));
+        definition.setFilterSelection(retrieverChain.getDataRetrieverLevel(0), functionFactory.createMethodWrappingFunction(getValueMethod), Arrays.asList(10, 100, 1000));
         
         return definition;
     }

java/com.sap.sse.datamining/src/com/sap/sse/datamining/DataMiningServer.java

@@ -55,8 +55,8 @@ public interface DataMiningServer {
             Class<DataSourceType> dataSourceType, Class<DataType> retrievedDataType);
     public <DataSourceType, DataType> DataRetrieverChainDefinition<DataSourceType, DataType> getDataRetrieverChainDefinition(UUID id);
     
-    public <DataSourceType> Query<HashSet<Object>> createDimensionValuesQuery(DataRetrieverChainDefinition<DataSourceType, ?> dataRetrieverChainDefinition, int retrieverLevel,
-            Iterable<Function<?>> dimensions, Map<Integer, Map<Function<?>, Collection<?>>> filterSelection, Locale locale);
+    public <DataSourceType> Query<HashSet<Object>> createDimensionValuesQuery(DataRetrieverChainDefinition<DataSourceType, ?> dataRetrieverChainDefinition, DataRetrieverLevel<?, ?> retrieverLevel,
+            Iterable<Function<?>> dimensions, Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection, Locale locale);
     public <DataSourceType, DataType, ExtractedType, ResultType> StatisticQueryDefinition<DataSourceType, DataType, ExtractedType, ResultType> getQueryDefinitionForDTO(StatisticQueryDefinitionDTO queryDefinitionDTO);
     public <DataSourceType, ResultType> Query<ResultType> createQuery(StatisticQueryDefinition<DataSourceType, ?, ?, ResultType> queryDefinition);
     public <ResultType> QueryResult<ResultType> runNewQueryAndAbortPreviousQueries(DataMiningSession session, Query<ResultType> query);

java/com.sap.sse.datamining/src/com/sap/sse/datamining/StatisticQueryDefinition.java

@@ -8,6 +8,7 @@ import java.util.Map;
 import com.sap.sse.datamining.components.AggregationProcessorDefinition;
 import com.sap.sse.datamining.components.DataRetrieverChainDefinition;
 import com.sap.sse.datamining.functions.Function;
+import com.sap.sse.datamining.impl.components.DataRetrieverLevel;
 
 public interface StatisticQueryDefinition<DataSourceType, DataType, ExtractedType, ResultType> {
 
@@ -19,7 +20,7 @@ public interface StatisticQueryDefinition<DataSourceType, DataType, ExtractedTyp
     public Locale getLocale();
     
     public DataRetrieverChainDefinition<DataSourceType, DataType> getDataRetrieverChainDefinition();
-    public Map<Integer, Map<Function<?>, Collection<?>>> getFilterSelection();
+    public Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> getFilterSelection();
     public List<Function<?>> getDimensionsToGroupBy();
     public Function<ExtractedType> getStatisticToCalculate();
     public AggregationProcessorDefinition<ExtractedType, ResultType> getAggregatorDefinition();

java/com.sap.sse.datamining/src/com/sap/sse/datamining/components/DataRetrieverChainBuilder.java

@@ -1,5 +1,7 @@
 package com.sap.sse.datamining.components;
 
+import com.sap.sse.datamining.impl.components.DataRetrieverLevel;
+
 
 /**
  * Used to construct a chain of retriever processors step by step. Allows to set the filter and result
@@ -11,6 +13,11 @@ package com.sap.sse.datamining.components;
  */
 public interface DataRetrieverChainBuilder<DataSourceType> {
     
+    /**
+     * @return <code>true</code>, if {@link #canStepFurther()} has been called.
+     */
+    public boolean hasBeenInitialized();
+    
     /**
      * @return <code>true</code>, if there's a next data retriever in the chain.
      */
@@ -30,9 +37,9 @@ public interface DataRetrieverChainBuilder<DataSourceType> {
     public Class<?> getCurrentRetrievedDataType();
     
     /**
-     * @return The current retriever level or <code>-1</code> if {@link #stepFurther()} has not yet been called.
+     * @return The current retriever level or <code>null</code> if {@link #stepFurther()} has not yet been called.
      */
-    public int getCurrentRetrieverLevel();
+    public DataRetrieverLevel<?, ?> getCurrentRetrieverLevel();
 
     /**
      * Sets the filter for the data retriever of the current level.

java/com.sap.sse.datamining/src/com/sap/sse/datamining/components/DataRetrieverChainDefinition.java

@@ -108,6 +108,12 @@ public interface DataRetrieverChainDefinition<DataSourceType, DataType> {
      */
     public List<? extends DataRetrieverLevel<?, ?>> getDataRetrieverLevels();
 
+    /**
+     * @param levelIndex
+     * @return The retriever level for the given index or <code>null</code>, if the index is out of bounds.
+     */
+    public DataRetrieverLevel<?, ?> getDataRetrieverLevel(int levelIndex);
+
     /**
      * Returns a {@link DataRetrieverChainBuilder}, that is used to construct the chain. {@link #endWith(Class, Class, Class, String)}
      * has to be called before you can use this method. Otherwise an exception will be thrown.

java/com.sap.sse.datamining/src/com/sap/sse/datamining/factories/QueryFactory.java

@@ -22,6 +22,7 @@ import com.sap.sse.datamining.functions.ParameterizedFunction;
 import com.sap.sse.datamining.impl.AdditionalDimensionValuesQueryData;
 import com.sap.sse.datamining.impl.AdditionalStatisticQueryData;
 import com.sap.sse.datamining.impl.ProcessorQuery;
+import com.sap.sse.datamining.impl.components.DataRetrieverLevel;
 import com.sap.sse.datamining.impl.components.GroupedDataEntry;
 import com.sap.sse.datamining.impl.criterias.AndCompoundFilterCriterion;
 import com.sap.sse.datamining.impl.criterias.CompoundFilterCriterion;
@@ -49,7 +50,7 @@ public class QueryFactory {
                 Processor<DataType, GroupedDataEntry<DataType>> groupingProcessor = processorFactory.createGroupingProcessor(dataTypeToRetrieve, extractionProcessor, getParameterProvidersFor(queryDefinition.getDimensionsToGroupBy(), stringMessages, queryDefinition.getLocale()));
 
                 DataRetrieverChainBuilder<DataSourceType> chainBuilder = queryDefinition.getDataRetrieverChainDefinition().startBuilding(executor);
-                Map<Integer, FilterCriterion<?>> criteriaMappedByRetrieverLevel = createFilterCriteria(queryDefinition.getFilterSelection());
+                Map<DataRetrieverLevel<?, ?>, FilterCriterion<?>> criteriaMappedByRetrieverLevel = createFilterCriteria(queryDefinition.getFilterSelection());
                 while (chainBuilder.canStepFurther()) {
                     chainBuilder.stepFurther();
                     
@@ -98,9 +99,9 @@ public class QueryFactory {
     }
 
     @SuppressWarnings("unchecked")
-    private <DataType> Map<Integer, FilterCriterion<?>> createFilterCriteria(Map<Integer, Map<Function<?>, Collection<?>>> filterSelection) {
-        Map<Integer, CompoundFilterCriterion<?>> criteriaMappedByRetrieverLevel = new HashMap<>();
-        for (Entry<Integer, Map<Function<?>, Collection<?>>> levelFilterSelection : filterSelection.entrySet()) {
+    private <DataType> Map<DataRetrieverLevel<?, ?>, FilterCriterion<?>> createFilterCriteria(Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection) {
+        Map<DataRetrieverLevel<?, ?>, FilterCriterion<?>> criteriaMappedByRetrieverLevel = new HashMap<>();
+        for (Entry<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> levelFilterSelection : filterSelection.entrySet()) {
             for (Entry<Function<?>, Collection<?>> levelFilterSelectionEntry : levelFilterSelection.getValue().entrySet()) {
                 Function<?> function = levelFilterSelectionEntry.getKey();
                 ParameterProvider parameterProvider = ParameterProvider.NULL;
@@ -114,25 +115,25 @@ public class QueryFactory {
                 ((CompoundFilterCriterion<DataType>) criteriaMappedByRetrieverLevel.get(levelFilterSelection.getKey())).addCriteria(new FunctionValuesFilterCriterion<>(dataType, function, parameterProvider, filterValues));
             }
         }
-        return (Map<Integer, FilterCriterion<?>>)(Map<Integer, ?>) criteriaMappedByRetrieverLevel;
+        return criteriaMappedByRetrieverLevel;
     }
 
-    public <DataSource> Query<HashSet<Object>> createDimensionValuesQuery(DataSource dataSource,
-            final DataRetrieverChainDefinition<DataSource, ?> dataRetrieverChainDefinition, final int retrieverLevel,
-            final Iterable<Function<?>> dimensions, final Map<Integer, Map<Function<?>, Collection<?>>> filterSelection, final Locale locale,
+    public <DataSourceType> Query<HashSet<Object>> createDimensionValuesQuery(DataSourceType dataSource,
+            final DataRetrieverChainDefinition<DataSourceType, ?> dataRetrieverChainDefinition, final DataRetrieverLevel<?, ?> retrieverLevel,
+            final Iterable<Function<?>> dimensions, final Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection, final Locale locale,
             final ResourceBundleStringMessages stringMessages, final ExecutorService executor) {
         @SuppressWarnings("unchecked")
         Class<HashSet<Object>> resultType = (Class<HashSet<Object>>)(Class<?>) HashSet.class;
-        return new ProcessorQuery<HashSet<Object>, DataSource>(dataSource, stringMessages, locale, resultType, new AdditionalDimensionValuesQueryData(dataRetrieverChainDefinition.getID(), dimensions)) {
+        return new ProcessorQuery<HashSet<Object>, DataSourceType>(dataSource, stringMessages, locale, resultType, new AdditionalDimensionValuesQueryData(dataRetrieverChainDefinition.getID(), dimensions)) {
             @Override
-            protected Processor<DataSource, ?> createChainAndReturnFirstProcessor(Processor<Map<GroupKey, HashSet<Object>>, Void> resultReceiver) {
+            protected Processor<DataSourceType, ?> createChainAndReturnFirstProcessor(Processor<Map<GroupKey, HashSet<Object>>, Void> resultReceiver) {
                 ProcessorFactory processorFactory = new ProcessorFactory(executor);
                 
                 Processor<GroupedDataEntry<Object>, Map<GroupKey, HashSet<Object>>> valueCollector = processorFactory.createGroupedDataCollectingAsSetProcessor(/*query*/ this);
 
-                Map<Integer, FilterCriterion<?>> criteriaMappedByRetrieverLevel = createFilterCriteria(filterSelection);
-                DataRetrieverChainBuilder<DataSource> chainBuilder = dataRetrieverChainDefinition.startBuilding(executor);
-                while (chainBuilder.getCurrentRetrieverLevel() < retrieverLevel) {
+                Map<DataRetrieverLevel<?, ?>, FilterCriterion<?>> criteriaMappedByRetrieverLevel = createFilterCriteria(filterSelection);
+                DataRetrieverChainBuilder<DataSourceType> chainBuilder = dataRetrieverChainDefinition.startBuilding(executor);
+                while (!chainBuilder.hasBeenInitialized() || chainBuilder.getCurrentRetrieverLevel().getLevel() < retrieverLevel.getLevel()) {
                     chainBuilder.stepFurther();
                     
                     if (criteriaMappedByRetrieverLevel.containsKey(chainBuilder.getCurrentRetrieverLevel())) {

java/com.sap.sse.datamining/src/com/sap/sse/datamining/impl/DataMiningServerImpl.java

@@ -33,6 +33,7 @@ import com.sap.sse.datamining.impl.components.management.StrategyPerQueryTypeMan
 import com.sap.sse.datamining.shared.DataMiningSession;
 import com.sap.sse.datamining.shared.dto.StatisticQueryDefinitionDTO;
 import com.sap.sse.datamining.shared.impl.dto.AggregationProcessorDefinitionDTO;
+import com.sap.sse.datamining.shared.impl.dto.DataRetrieverLevelDTO;
 import com.sap.sse.datamining.shared.impl.dto.FunctionDTO;
 import com.sap.sse.datamining.shared.impl.dto.QueryResultDTO;
 import com.sap.sse.i18n.ResourceBundleStringMessages;
@@ -298,8 +299,8 @@ public class DataMiningServerImpl implements ModifiableDataMiningServer {
             AggregationProcessorDefinition<ExtractedType, ResultType> aggregatorDefinition = getAggregationProcessorDefinitionForDTO(queryDefinitionDTO.getAggregatorDefinition());
             queryDefinition = new ModifiableStatisticQueryDefinition<>(locale, retrieverChain, statisticToCalculate, aggregatorDefinition);
              
-            for (Entry<Integer, HashMap<FunctionDTO, HashSet<? extends Serializable>>> levelSpecificFilterSelection : queryDefinitionDTO.getFilterSelection().entrySet()) {
-                Integer retrieverLevel = levelSpecificFilterSelection.getKey();
+            for (Entry<DataRetrieverLevelDTO, HashMap<FunctionDTO, HashSet<? extends Serializable>>> levelSpecificFilterSelection : queryDefinitionDTO.getFilterSelection().entrySet()) {
+                DataRetrieverLevel<?, ?> retrieverLevel = retrieverChain.getDataRetrieverLevel(levelSpecificFilterSelection.getKey().getLevel());
                 for (Entry<FunctionDTO, HashSet<? extends Serializable>> levelSpecificFilterSelectionEntry : levelSpecificFilterSelection.getValue().entrySet()) {
                     Function<?> dimensionToFilterBy = getFunctionForDTO(levelSpecificFilterSelectionEntry.getKey());
                     if (dimensionToFilterBy != null) {
@@ -326,8 +327,8 @@ public class DataMiningServerImpl implements ModifiableDataMiningServer {
     }
 
     @Override
-    public <DataSourceType> Query<HashSet<Object>> createDimensionValuesQuery(DataRetrieverChainDefinition<DataSourceType, ?> dataRetrieverChainDefinition, int retrieverLevel,
-            Iterable<Function<?>> dimensions, Map<Integer, Map<Function<?>, Collection<?>>> filterSelection, Locale locale) {
+    public <DataSourceType> Query<HashSet<Object>> createDimensionValuesQuery(DataRetrieverChainDefinition<DataSourceType, ?> dataRetrieverChainDefinition, DataRetrieverLevel<?, ?> retrieverLevel,
+            Iterable<Function<?>> dimensions, Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection, Locale locale) {
         DataSourceProvider<DataSourceType> dataSourceProvider = getDataSourceProviderFor(dataRetrieverChainDefinition.getDataSourceType());
         return queryFactory.createDimensionValuesQuery(dataSourceProvider.getDataSource(), dataRetrieverChainDefinition, retrieverLevel, dimensions, filterSelection, locale, getStringMessages(), getExecutorService());
     }

java/com.sap.sse.datamining/src/com/sap/sse/datamining/impl/ModifiableStatisticQueryDefinition.java

@@ -11,13 +11,14 @@ import com.sap.sse.datamining.StatisticQueryDefinition;
 import com.sap.sse.datamining.components.AggregationProcessorDefinition;
 import com.sap.sse.datamining.components.DataRetrieverChainDefinition;
 import com.sap.sse.datamining.functions.Function;
+import com.sap.sse.datamining.impl.components.DataRetrieverLevel;
 
 public class ModifiableStatisticQueryDefinition<DataSourceType, DataType, ExtractedType, ResultType> implements StatisticQueryDefinition<DataSourceType, DataType, ExtractedType, ResultType> {
 
     private final Locale locale;
     
     private final DataRetrieverChainDefinition<DataSourceType, DataType> retrieverChain;
-    private final Map<Integer, Map<Function<?>, Collection<?>>> filterSelection;
+    private final Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> filterSelection;
     
     private final List<Function<?>> dimensionsToGroupBy;
     
@@ -67,7 +68,7 @@ public class ModifiableStatisticQueryDefinition<DataSourceType, DataType, Extrac
     }
 
     @Override
-    public Map<Integer, Map<Function<?>, Collection<?>>> getFilterSelection() {
+    public Map<DataRetrieverLevel<?, ?>, Map<Function<?>, Collection<?>>> getFilterSelection() {
         return filterSelection;
     }
 
@@ -86,7 +87,7 @@ public class ModifiableStatisticQueryDefinition<DataSourceType, DataType, Extrac
         return aggregatorDefinition;
     }
 
-    public void setFilterSelection(Integer retrieverLevel, Function<?> dimensionToFilterBy, Collection<?> filterSelection) {
+    public void setFilterSelection(DataRetrieverLevel<?, ?> retrieverLevel, Function<?> dimensionToFilterBy, Collection<?> filterSelection) {
         if (!this.filterSelection.containsKey(retrieverLevel)) {
             this.filterSelection.put(retrieverLevel, new HashMap<Function<?>, Collection<?>>());
         }

java/com.sap.sse.datamining/src/com/sap/sse/datamining/impl/components/SimpleDataRetrieverChainBuilder.java

@@ -109,8 +109,8 @@ public class SimpleDataRetrieverChainBuilder<DataSourceType> implements DataRetr
     }
     
     @Override
-    public int getCurrentRetrieverLevel() {
-        return currentRetrieverTypeIndex;
+    public DataRetrieverLevel<?, ?> getCurrentRetrieverLevel() {
+        return hasBeenInitialized() ? dataRetrieverTypesWithInformation.get(currentRetrieverTypeIndex) : null;
     }
 
     @SuppressWarnings("unchecked")
@@ -129,7 +129,7 @@ public class SimpleDataRetrieverChainBuilder<DataSourceType> implements DataRetr
         return (Processor<DataSourceType, ?>) firstRetriever;
     }
 
-    private boolean hasBeenInitialized() {
+    public boolean hasBeenInitialized() {
         return currentRetrieverTypeIndex >= 0;
     }
     

java/com.sap.sse.datamining/src/com/sap/sse/datamining/impl/components/SimpleDataRetrieverChainDefinition.java

@@ -128,6 +128,14 @@ public class SimpleDataRetrieverChainDefinition<DataSourceType, DataType> implem
     public List<? extends DataRetrieverLevel<?, ?>> getDataRetrieverLevels() {
         return dataRetrieverTypesWithInformation;
     }
+    
+    @Override
+    public DataRetrieverLevel<?, ?> getDataRetrieverLevel(int levelIndex) {
+        if (levelIndex < 0 || levelIndex >= getDataRetrieverLevels().size()) {
+            return null;
+        }
+        return getDataRetrieverLevels().get(levelIndex);
+    }
 
     @Override
     public DataRetrieverChainBuilder<DataSourceType> startBuilding(ExecutorService executor) {