Dépôt officiel du code source de l'ERP OpenConcerto

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2011 OpenConcerto, by ILM Informatique. All rights reserved.

 *

 * The contents of this file are subject to the terms of the GNU General Public License Version 3

 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a

 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific

 * language governing permissions and limitations under the License.

 *

 * When distributing the software, include this License Header Notice in each file.

 */

 /*

 * Créé le 14 avr. 2005

 */

package org.openconcerto.utils;

import org.openconcerto.utils.cc.ITransformer;

import java.math.BigDecimal;

import java.util.Collection;

import java.util.Comparator;

import java.util.Iterator;

import java.util.LinkedHashMap;

import java.util.List;

/**

 * @author Sylvain CUAZ

 */

public class CompareUtils {

    /**

     * Compare 2 nombres entier avec longValue().

     *

     * @param n1 le premier nombre.

     * @param n2 le deuxième nombre.

     * @return 0 si ==, >0 si n1>2.

     */

    public static final int compareIntNumbers(Number n1, Number n2) {

        return compareLong(n1.longValue(), n2.longValue());

    }

    static public final int compareInt(int int1, int int2) {

        if (int1 < int2)

            return -1;

        else if (int1 == int2)

            return 0;

        else

            return +1;

    }

    static public final int compareLong(long int1, long int2) {

        if (int1 < int2)

            return -1;

        else if (int1 == int2)

            return 0;

        else

            return +1;

    }

    /**

     * Compare two objects if they're numbers or comparable.

     *

     * @param o1 first object.

     * @param o2 second object.

     * @return a negative integer, zero, or a positive integer as o1 is less than, equal to, or

     *         greater than o2.

     * @throws ClassCastException if o1 is neither a {@link Number} nor a {@link Comparable}, or if

     *         o2's type prevents it from being compared to o1.

     * @throws NullPointerException if o1 or o2 is <code>null</code>.

     * @see Comparable#compareTo(Object)

     * @see NumberUtils#compare(Number, Number)

     */

    static public final int compare(final Object o1, final Object o2) throws ClassCastException {

        if (o1 == null || o2 == null)

            throw new NullPointerException();

        if (o1 instanceof Number && o2 instanceof Number) {

            return NumberUtils.compare((Number) o1, (Number) o2);

        } else {

            // see Arrays.mergeSort()

            @SuppressWarnings({ "rawtypes", "unchecked" })

            final int res = ((Comparable) o1).compareTo(o2);

            return res;

        }

    }

    static private final Comparator<Comparable<Object>> NATURAL_COMPARATOR = new Comparator<Comparable<Object>>() {

        @Override

        public int compare(Comparable<Object> o1, Comparable<Object> o2) {

            return o1.compareTo(o2);

        }

    };

    // added in Comparator in Java 8

    @SuppressWarnings("unchecked")

    static public final <T extends Comparable<? super T>> Comparator<T> naturalOrder() {

        return (Comparator<T>) NATURAL_COMPARATOR;

    }

    /**

     * Renvoie un comparateur qui utilise successivement la liste passée tant que les objets sont

     * égaux.

     *

     * @param comparators une liste de Comparator.

     * @return le Comparator demandé.

     * @param <T> type of comparator

     */

    static public final <T> Comparator<T> createComparator(final List<? extends Comparator<T>> comparators) {

        return new Comparator<T>() {

            public String toString() {

                return "CompareUtils comparator with " + comparators;

            }

            public int compare(T o1, T o2) {

                int result = 0;

                int i = 0;

                while (i < comparators.size() && result == 0) {

                    final Comparator<T> transf = comparators.get(i);

                    result = transf.compare(o1, o2);

                    i++;

                }

                return result;

            }

        };

    }

    /**

     * Compare 2 objets pouvant être <code>null</code>.

     *

     * @param o1 the first object, can be <code>null</code>.

     * @param o2 the second object, can be <code>null</code>.

     * @return <code>true</code> if both are <code>null</code> or if o1.equals(o2).

     * @see Object#equals(Object)

     */

    static public final boolean equals(Object o1, Object o2) {

        if (o1 == null && o2 == null)

            return true;

        if (o1 == null || o2 == null)

            return false;

        return o1.equals(o2);

    }

    /**

     * Compare 2 objets pouvant être <code>null</code> avec compareTo(). Useful since for some

     * classes equals() is more specific than compareTo()==0, e.g. {@link BigDecimal#equals(Object)}

     * doesn't compare the numeric value but instance variables (1E2 is not equal to 100 or 100.00).

     *

     * @param o1 the first object, can be <code>null</code>.

     * @param o2 the second object, can be <code>null</code>.

     * @return <code>true</code> if both are <code>null</code> or if o1.compareTo(o2) == 0.

     * @see Comparable#compareTo(Object)

     */

    static public final <T> boolean equalsWithCompareTo(Comparable<T> o1, T o2) {

        if (o1 == null && o2 == null)

            return true;

        if (o1 == null || o2 == null)

            return false;

        return o1.compareTo(o2) == 0;

    }

    /**

     * Compare 2 collections in order. Useful since for some classes even though there's an order

     * <code>equals()</code> ignores it (e.g. {@link LinkedHashMap#equals(Object)}).

     *

     * @param c1 the first object, can be <code>null</code>.

     * @param c2 the second object, can be <code>null</code>.

     * @return <code>true</code> if both are <code>null</code> or if all items in order are

     *         {@link #equals(Object, Object)}.

     */

    static public final boolean equalsUsingIterator(Collection<?> c1, Collection<?> c2) {

        if (c1 == null && c2 == null)

            return true;

        if (c1 == null || c2 == null)

            return false;

        final int size = c1.size();

        if (size != c2.size())

            return false;

        else if (size == 0)

            return true;

        final Iterator<?> iter1 = c1.iterator();

        final Iterator<?> iter2 = c2.iterator();

        while (iter1.hasNext()) {

            final Object o1 = iter1.next();

            final Object o2 = iter2.next();

            if (!equals(o1, o2))

                return false;

        }

        assert !iter1.hasNext() && !iter2.hasNext();

        return true;

    }

    static public interface Equalizer<T> {

        public boolean equals(T o1, T o2);

    }

    static public final Equalizer<Object> OBJECT_EQ = new Equalizer<Object>() {

        public boolean equals(Object o1, Object o2) {

            return CompareUtils.equals(o1, o2);

        }

    };

    static public final <T> boolean equals(List<T> l1, List<T> l2, Equalizer<? super T> comp) {

        return compare(l1, l2, comp, null) == null;

    }

    /**

     * Compare two lists using the provided comparator.

     *

     * @param <T> type of items

     * @param l1 the first list.

     * @param l2 the second list.

     * @param comp how to compare each item.

     * @param toString how to dispay items, can be <code>null</code>.

     * @return <code>null</code> if the two lists are equal, otherwise a String explaining the

     *         difference.

     */

    static public final <T> String compare(List<T> l1, List<T> l2, Equalizer<? super T> comp, final ITransformer<? super T, String> toString) {

        final int size = l1.size();

        if (size != l2.size())

            return "unequal size";

        for (int i = 0; i < size; i++) {

            final T o1 = l1.get(i);

            final T o2 = l2.get(i);

            if (!comp.equals(o1, o2)) {

                final String s1 = toString == null ? String.valueOf(o1) : toString.transformChecked(o1);

                final String s2 = toString == null ? String.valueOf(o2) : toString.transformChecked(o2);

                return "unequal at " + i + ": " + s1 + " != " + s2;

            }

        }

        return null;

    }

}