diff -r 5ae3e5665a0b -r cc93757aeca3 src/net/fortuna/ical4j/model/NumberList.java
--- a/src/net/fortuna/ical4j/model/NumberList.java	Thu Feb 12 18:02:00 2015 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,154 +0,0 @@
-/**
- * Copyright (c) 2012, Ben Fortuna
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- *  o Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *
- *  o Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- *  o Neither the name of Ben Fortuna nor the names of any other contributors
- * may be used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
- * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
- * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
- * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
- * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-package net.fortuna.ical4j.model;
-
-import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.StringTokenizer;
-
-import net.fortuna.ical4j.util.Numbers;
-
-/**
- * $Id$ [29-May-2004]
- *
- * Defines a list of numbers.
- * 
- * @author Ben Fortuna
- */
-public class NumberList extends ArrayList implements Serializable {
-    
-    private static final long serialVersionUID = -1667481795613729889L;
-
-    private final int minValue;
-    
-    private final int maxValue;
-
-    private final boolean allowsNegativeValues;
-    
-    /**
-     * Default constructor.
-     */
-    public NumberList() {
-    	this(Integer.MIN_VALUE, Integer.MAX_VALUE, true);
-    }
-
-    /**
-     * Constructor with limits.
-     * @param minValue the minimum allowable value
-     * @param maxValue the maximum allowable value
-     * @param allowsNegativeValues indicates whether negative values are allowed
-     */
-    public NumberList(int minValue, int maxValue, boolean allowsNegativeValues) {
-    	this.minValue = minValue;
-    	this.maxValue = maxValue;
-        this.allowsNegativeValues = allowsNegativeValues;
-    }
-
-    /**
-     * Constructor.
-     * @param aString a string representation of a number list
-     */
-    public NumberList(final String aString) {
-    	this(aString, Integer.MIN_VALUE, Integer.MAX_VALUE, true);
-    }
-    
-    /**
-     * @param aString a string representation of a number list
-     * @param minValue the minimum allowable value
-     * @param maxValue the maximum allowable value
-     * @param allowsNegativeValues indicates whether negative values are allowed
-     */
-    public NumberList(final String aString, int minValue, int maxValue, boolean allowsNegativeValues) {
-    	this(minValue, maxValue, allowsNegativeValues);
-        final StringTokenizer t = new StringTokenizer(aString, ",");
-        while (t.hasMoreTokens()) {
-        	final int value = Numbers.parseInt(t.nextToken());
-            add(new Integer(value));
-        }
-    }
-
-    /**
-     * @param aNumber a number to add to the list
-     * @return true if the number was added, otherwise false
-     */
-    public final boolean add(final Integer aNumber) {
-        int abs = aNumber.intValue();
-        if ((abs >> 31 | -abs >>> 31) < 0) {
-            if (!allowsNegativeValues) {
-                throw new IllegalArgumentException("Negative value not allowed: " + aNumber);
-            }
-            abs = Math.abs(abs);
-        }
-    	if (abs < minValue || abs > maxValue) {
-    		throw new IllegalArgumentException(
-    		        "Value not in range [" + minValue + ".." + maxValue + "]: " + aNumber);
-    	}
-        return add((Object) aNumber);
-    }
-    
-    /**
-     * Overrides superclass to throw an <code>IllegalArgumentException</code>
-     * where argument is not a <code>java.lang.Integer</code>.
-     * @param arg0 an object to add
-     * @return true if the object was added, otherwise false
-     * @see java.util.List#add(Object)
-     */
-    public final boolean add(final Object arg0) {
-        if (!(arg0 instanceof Integer)) {
-            throw new IllegalArgumentException("Argument not a " + Integer.class.getName());
-        }
-        return super.add(arg0);
-    }
-
-    /**
-     * @param aNumber a number to remove from the list
-     * @return true if the number was removed, otherwise false
-     */
-    public final boolean remove(final Integer aNumber) {
-        return remove((Object) aNumber);
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    public final String toString() {
-        final StringBuffer b = new StringBuffer();
-        for (final Iterator i = iterator(); i.hasNext();) {
-            b.append(i.next());
-            if (i.hasNext()) {
-                b.append(',');
-            }
-        }
-        return b.toString();
-    }
-}