Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2012 Davide Mottin <mottin@disi.unitn.eu>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

import java.util.Comparator;

import java.util.List;

public class Main {
    /**
     *
     * @param <T>
     * @param list
     * @param element
     * @param c
     * @return the position of the element if present, -1 otherwise
     */
    public static <T extends Comparable<? super T>> int binarySearchOf(List<T> list, T element,
            Comparator<? super T> c) {
        return binarySearchOf(list, element, 0, list.size(), c);
    }

    /**
     *
     * @param <T>
     * @param list
     * @param element
     * @return the position of the element if present, -1 otherwise
     */
    public static <T extends Comparable<? super T>> int binarySearchOf(List<T> list, T element) {
        return binarySearchOf(list, element, 0, list.size(), null);
    }

    /**
     *
     * @param <T>
     * @param list
     * @param element
     * @param start
     * @param end
     * @param c
     * @return the position of the element if present, -1 otherwise
     */
    public static <T extends Comparable<? super T>> int binarySearchOf(List<T> list, T element, int start, int end,
            Comparator<? super T> c) {
        int mid = (start + end) / 2;
        if (start > end || mid >= end) {
            return -1;
        }
        int compared = -1;
        try {
            compared = c == null ? list.get(mid).compareTo(element) : c.compare(list.get(mid), element);
        } catch (Exception e) {
            throw new IllegalStateException(
                    "Exception while searching for " + element + " from " + start + " to " + end, e);
        }

        if (compared == 0) {
            return mid;
        } else if (compared < 0) {
            return binarySearchOf(list, element, mid + 1, end, c);
        } else {
            return binarySearchOf(list, element, start, mid, c);
        }
    }
}