Add creator method for LMApproximator

Author: easbar

core/src/main/java/com/graphhopper/routing/lm/LMApproximator.java

@@ -49,6 +49,10 @@ public class LMApproximator implements WeightApproximator {
     private final WeightApproximator fallBackApproximation;
     private boolean fallback = false;
 
+    public static LMApproximator forLandmarks(Graph g, LandmarkStorage lms, int activeLM) {
+        return new LMApproximator(g, lms.getWeighting(), lms.getBaseNodes(), lms, activeLM, lms.getFactor(), false);
+    }
+
     public LMApproximator(Graph graph, Weighting weighting, int maxBaseNodes, LandmarkStorage lms, int activeCount,
                           double factor, boolean reverse) {
         this.reverse = reverse;

core/src/main/java/com/graphhopper/routing/lm/LMRoutingAlgorithmFactory.java

@@ -30,14 +30,10 @@
 
 public class LMRoutingAlgorithmFactory implements RoutingAlgorithmFactory {
     private final LandmarkStorage lms;
-    private final Weighting prepareWeighting;
-    private final int numBaseNodes;
     private int defaultActiveLandmarks;
 
     public LMRoutingAlgorithmFactory(LandmarkStorage lms) {
         this.lms = lms;
-        this.prepareWeighting = lms.getWeighting();
-        this.numBaseNodes = lms.getBaseNodes();
         this.defaultActiveLandmarks = Math.max(1, Math.min(lms.getLandmarkCount() / 2, 12));
     }
 
@@ -85,7 +81,6 @@ public RoutingAlgorithm createAlgo(Graph g, AlgorithmOptions opts) {
     }
 
     private LMApproximator getApproximator(Graph g, int activeLM, double epsilon) {
-        return new LMApproximator(g, prepareWeighting, numBaseNodes, lms, activeLM, lms.getFactor(), false).
-                setEpsilon(epsilon);
+        return LMApproximator.forLandmarks(g, lms, activeLM).setEpsilon(epsilon);
     }
 }