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diff --git a/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/hull/AbstractConvexHullGenerator2D.java b/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/hull/AbstractConvexHullGenerator2D.java
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+++ b/src/main/java/org/apache/commons/math3/geometry/euclidean/twod/hull/AbstractConvexHullGenerator2D.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.math3.geometry.euclidean.twod.hull;
+
+import java.util.Collection;
+
+import org.apache.commons.math3.exception.ConvergenceException;
+import org.apache.commons.math3.exception.MathIllegalArgumentException;
+import org.apache.commons.math3.exception.NullArgumentException;
+import org.apache.commons.math3.geometry.euclidean.twod.Vector2D;
+import org.apache.commons.math3.util.MathUtils;
+
+/**
+ * Abstract base class for convex hull generators in the two-dimensional euclidean space.
+ *
+ * @since 3.3
+ */
+abstract class AbstractConvexHullGenerator2D implements ConvexHullGenerator2D {
+
+    /** Default value for tolerance. */
+    private static final double DEFAULT_TOLERANCE = 1e-10;
+
+    /** Tolerance below which points are considered identical. */
+    private final double tolerance;
+
+    /**
+     * Indicates if collinear points on the hull shall be present in the output.
+     * If {@code false}, only the extreme points are added to the hull.
+     */
+    private final boolean includeCollinearPoints;
+
+    /**
+     * Simple constructor.
+     * <p>
+     * The default tolerance (1e-10) will be used to determine identical points.
+     *
+     * @param includeCollinearPoints indicates if collinear points on the hull shall be
+     * added as hull vertices
+     */
+    protected AbstractConvexHullGenerator2D(final boolean includeCollinearPoints) {
+        this(includeCollinearPoints, DEFAULT_TOLERANCE);
+    }
+
+    /**
+     * Simple constructor.
+     *
+     * @param includeCollinearPoints indicates if collinear points on the hull shall be
+     * added as hull vertices
+     * @param tolerance tolerance below which points are considered identical
+     */
+    protected AbstractConvexHullGenerator2D(final boolean includeCollinearPoints, final double tolerance) {
+        this.includeCollinearPoints = includeCollinearPoints;
+        this.tolerance = tolerance;
+    }
+
+    /**
+     * Get the tolerance below which points are considered identical.
+     * @return the tolerance below which points are considered identical
+     */
+    public double getTolerance() {
+        return tolerance;
+    }
+
+    /**
+     * Returns if collinear points on the hull will be added as hull vertices.
+     * @return {@code true} if collinear points are added as hull vertices, or {@code false}
+     * if only extreme points are present.
+     */
+    public boolean isIncludeCollinearPoints() {
+        return includeCollinearPoints;
+    }
+
+    /** {@inheritDoc} */
+    public ConvexHull2D generate(final Collection<Vector2D> points)
+            throws NullArgumentException, ConvergenceException {
+        // check for null points
+        MathUtils.checkNotNull(points);
+
+        Collection<Vector2D> hullVertices = null;
+        if (points.size() < 2) {
+            hullVertices = points;
+        } else {
+            hullVertices = findHullVertices(points);
+        }
+
+        try {
+            return new ConvexHull2D(hullVertices.toArray(new Vector2D[hullVertices.size()]),
+                                    tolerance);
+        } catch (MathIllegalArgumentException e) {
+            // the hull vertices may not form a convex hull if the tolerance value is to large
+            throw new ConvergenceException();
+        }
+    }
+
+    /**
+     * Find the convex hull vertices from the set of input points.
+     * @param points the set of input points
+     * @return the convex hull vertices in CCW winding
+     */
+    protected abstract Collection<Vector2D> findHullVertices(Collection<Vector2D> points);
+
+}