bug5207: rounded off the implementation of the caching

java/com.sap.sailing.domain.common/src/com/sap/sailing/domain/common/orc/AverageWindOnLegCache.java

@@ -0,0 +1,15 @@
+package com.sap.sailing.domain.common.orc;
+
+import java.util.function.Function;
+
+import com.sap.sailing.domain.common.Wind;
+
+public interface AverageWindOnLegCache {
+    /**
+     * Caches the legs by their {@link Object#equals(Object) equality and allows for one wind reading per such leg.
+     * If you want to map differently-scaled "variants" of the same original leg (e.g., because of different distances
+     * traveled on that leg) as the same key then you'll have to come up with a wrapper around your leg that
+     * has a definition of equality using only the underlying original leg for comparison.
+     */
+    <L extends ORCPerformanceCurveLeg> Wind getAverageWind(L leg, Function<L, Wind> averageWindForLegSupplier);
+}