Minimized the resulting dimension set for a data retriever chain

java/com.sap.sailing.datamining/src/com/sap/sailing/datamining/factories/SailingDataMiningFactory.java

@@ -17,6 +17,7 @@ import com.sap.sse.datamining.DataRetrieverChainDefinition;
 import com.sap.sse.datamining.Query;
 import com.sap.sse.datamining.components.FilterCriterion;
 import com.sap.sse.datamining.components.Processor;
+import com.sap.sse.datamining.factories.FunctionFactory;
 import com.sap.sse.datamining.factories.ProcessorFactory;
 import com.sap.sse.datamining.functions.Function;
 import com.sap.sse.datamining.functions.FunctionProvider;
@@ -37,12 +38,14 @@ import com.sap.sse.datamining.shared.impl.dto.DataRetrieverChainDefinitionDTO;
 public class SailingDataMiningFactory {
 
     private final ProcessorFactory processorFactory;
+    private final FunctionFactory functionFactory;
     
     private final FunctionProvider functionProvider;
     private final DataRetrieverChainDefinitionRegistry dataRetrieverChainDefinitionRegistry;
 
     public SailingDataMiningFactory(FunctionProvider functionProvider, DataRetrieverChainDefinitionRegistry dataRetrieverChainDefinitionRegistry) {
         processorFactory = new ProcessorFactory(DataMiningActivator.getExecutor());
+        functionFactory = new FunctionFactory();
         
         this.functionProvider = functionProvider;
         this.dataRetrieverChainDefinitionRegistry = dataRetrieverChainDefinitionRegistry;
@@ -150,12 +153,36 @@ public class SailingDataMiningFactory {
     private Collection<Function<?>> getDimensionsOf(
             DataRetrieverChainDefinition<RacingEventService> dataRetrieverChainDefinition) {
         Collection<Function<?>> dimensions = new HashSet<>();
-        for (DataRetrieverTypeWithInformation<?, ?> dataRetrieverTypeWithInformation : dataRetrieverChainDefinition.getDataRetrieverTypesWithInformation()) {
-            dimensions.addAll(functionProvider.getDimensionsFor(dataRetrieverTypeWithInformation.getRetrievedDataType()));
+        List<? extends DataRetrieverTypeWithInformation<?, ?>> dataRetrieverTypesWithInformation = dataRetrieverChainDefinition.getDataRetrieverTypesWithInformation();
+        for (int i = dataRetrieverTypesWithInformation.size() - 1; i >= 0; i--) {
+            DataRetrieverTypeWithInformation<?, ?> dataRetrieverTypeWithInformation = dataRetrieverTypesWithInformation.get(i);
+            Collection<Function<?>> dimensionsOfDataType = functionProvider.getDimensionsFor(dataRetrieverTypeWithInformation.getRetrievedDataType());
+            
+            if (!dimensions.isEmpty()) {
+                Map<Function<?>, Function<?>> dimensionsMappedByTrimmedDimensions = trimFirstMethodAndMapOriginal(dimensions);
+                for (Function<?> dimensionOfDataType : dimensionsOfDataType) {
+                    if (dimensionsMappedByTrimmedDimensions.containsKey(dimensionOfDataType)) {
+                        dimensions.remove(dimensionsMappedByTrimmedDimensions.get(dimensionOfDataType));
+                    }
+                }
+            }
+            
+            dimensions.addAll(dimensionsOfDataType);
         }
         return dimensions;
     }
     
+    private Map<Function<?>, Function<?>> trimFirstMethodAndMapOriginal(Collection<Function<?>> dimensions) {
+        Map<Function<?>, Function<?>> dimensionsMappedByTrimmedDimensions = new HashMap<>();
+        for (Function<?> dimension : dimensions) {
+            Function<?> trimmedDimension = functionFactory.trimFirstMethod(dimension);
+            if (trimmedDimension != null) {
+                dimensionsMappedByTrimmedDimensions.put(trimmedDimension, dimension);
+            }
+        }
+        return dimensionsMappedByTrimmedDimensions;
+    }
+
     private Map<Class<?>, Collection<Function<?>>> mapFunctionsByDeclaringType(Collection<Function<?>> functions) {
         Map<Class<?>, Collection<Function<?>>> mappedFunctions = new HashMap<>();
         for (Function<?> function : functions) {

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

@@ -3,9 +3,11 @@ package com.sap.sse.datamining.impl;
 import static org.hamcrest.Matchers.greaterThan;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.lessThanOrEqualTo;
+import static org.hamcrest.Matchers.not;
 import static org.junit.Assert.assertThat;
 
 import java.util.Collection;
+import java.util.List;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -14,7 +16,6 @@ import com.sap.sse.datamining.DataRetrieverChainBuilder;
 import com.sap.sse.datamining.DataRetrieverChainDefinition;
 import com.sap.sse.datamining.components.FilterCriterion;
 import com.sap.sse.datamining.components.Processor;
-import com.sap.sse.datamining.impl.SimpleDataRetrieverChainDefinition;
 import com.sap.sse.datamining.impl.criterias.AbstractFilterCriterion;
 import com.sap.sse.datamining.test.functions.registry.test_classes.Test_Regatta;
 import com.sap.sse.datamining.test.functions.registry.test_contexts.Test_HasLegOfCompetitorContext;
@@ -85,8 +86,10 @@ public class TestDataRetrieverChainCreation {
         assertThat(chainClone.getDataSourceType().equals(dataRetrieverChainDefinition.getDataSourceType()), is(true));
         assertThat(chainClone.getRetrievedDataType().equals(dataRetrieverChainDefinition.getRetrievedDataType()), is(true));
         
-        Collection<DataRetrieverTypeWithInformation<?, ?>> cloneDataRetrieverTypesWithInformation = (Collection<DataRetrieverTypeWithInformation<?, ?>>) chainClone.getDataRetrieverTypesWithInformation();
+        List<DataRetrieverTypeWithInformation<?, ?>> cloneDataRetrieverTypesWithInformation = (List<DataRetrieverTypeWithInformation<?, ?>>) chainClone.getDataRetrieverTypesWithInformation();
         assertThat(cloneDataRetrieverTypesWithInformation, is(dataRetrieverChainDefinition.getDataRetrieverTypesWithInformation()));
+        
+        assertThat(chainClone.getUUID(), not(dataRetrieverChainDefinition.getUUID()));
     }
 
     @SuppressWarnings("unchecked")

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

@@ -1,6 +1,6 @@
 package com.sap.sse.datamining;
 
-import java.util.Collection;
+import java.util.List;
 import java.util.Locale;
 import java.util.UUID;
 import java.util.concurrent.ExecutorService;
@@ -32,7 +32,7 @@ public interface DataRetrieverChainDefinition<DataSourceType> {
                      Class<Processor<NextInputType, NextResultType>> nextRetrieverType,
                      Class<NextResultType> retrievedDataType);
     
-    public Collection<? extends DataRetrieverTypeWithInformation<?, ?>> getDataRetrieverTypesWithInformation();
+    public List<? extends DataRetrieverTypeWithInformation<?, ?>> getDataRetrieverTypesWithInformation();
 
     public DataRetrieverChainBuilder<DataSourceType> startBuilding(ExecutorService executor);
 

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

@@ -42,4 +42,25 @@ public class FunctionFactory {
         return createCompoundFunction(name, functions);
     }
 
+    /**
+     * Creates a new Function for the given function, without the first method in the list.</br> 
+     * @return A new CompoundFunction without the first method in the list or <code>null</code>, if the given
+     * function is no CompoundFunction or the method list has the size of 1. 
+     */
+    public Function<?> trimFirstMethod(Function<?> function) {
+        if (function instanceof ConcatenatingCompoundFunction<?>) {
+            ConcatenatingCompoundFunction<?> compoundFunction = (ConcatenatingCompoundFunction<?>) function;
+            List<Function<?>> methodList = compoundFunction.getFunctions();
+            if (methodList.size() > 1) {
+                List<Function<?>> trimmedMethodList = new ArrayList<>();
+                for (int i = 1; i < methodList.size(); i++) {
+                    trimmedMethodList.add(methodList.get(i));
+                }
+                return trimmedMethodList.size() == 1 ? trimmedMethodList.get(0) : createCompoundFunction(trimmedMethodList);
+            }
+        }
+        
+        return null;
+    }
+
 }

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

@@ -104,7 +104,7 @@ public class SimpleDataRetrieverChainDefinition<DataSourceType> implements
     }
     
     @Override
-    public Collection<? extends DataRetrieverTypeWithInformation<?, ?>> getDataRetrieverTypesWithInformation() {
+    public List<? extends DataRetrieverTypeWithInformation<?, ?>> getDataRetrieverTypesWithInformation() {
         return dataRetrieverTypesWithInformation;
     }
 

java/com.sap.sse.datamining/src/com/sap/sse/datamining/impl/functions/ConcatenatingCompoundFunction.java

@@ -156,6 +156,10 @@ public class ConcatenatingCompoundFunction<ReturnType> extends AbstractFunction<
     public int getOrdinal() {
         return ordinal;
     }
+    
+    public List<Function<?>> getFunctions() {
+        return functions;
+    }
 
     private Function<?> getFirstFunction() {
         return functions.get(0);