rs.in.zivanovic.jdepmon.core.VersionComparator.java Source code

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Here is the source code for rs.in.zivanovic.jdepmon.core.VersionComparator.java

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/*
 * The MIT License
 *
 * Copyright 2015 Marko Zivanovic <marko@zivanovic.in.rs>.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package rs.in.zivanovic.jdepmon.core;

import com.google.common.base.CharMatcher;
import com.google.common.base.Splitter;
import java.util.Comparator;
import java.util.List;

/**
 * Compare two version strings. Version strings are split into components and each components is compared as number, if
 * it can be parsed as such, or as a string otherwise. If all components up to the length of the shorter version string
 * are equal, shorter version has precedence.
 */
public class VersionComparator implements Comparator<String> {

    private static final String SEPARATORS = ".-+";

    @Override
    public int compare(String o1, String o2) {
        List<String> comps1 = Splitter.on(CharMatcher.anyOf(SEPARATORS)).splitToList(o1);
        List<String> comps2 = Splitter.on(CharMatcher.anyOf(SEPARATORS)).splitToList(o2);
        int res = 0;
        int ssize = comps1.size() >= comps2.size() ? comps2.size() : comps1.size();
        int i = 0;
        Comparable comp1, comp2;
        while (i < ssize) {
            try {
                comp1 = Long.parseLong(comps1.get(i));
                comp2 = Long.parseLong(comps2.get(i));
            } catch (NumberFormatException ex) {
                comp1 = comps1.get(i).toLowerCase();
                comp2 = comps2.get(i).toLowerCase();
            }
            res = comp1.compareTo(comp2);
            if (res != 0) {
                break;
            }
            i = i + 1;
        }
        if (res == 0 && comps1.size() != comps2.size()) {
            res = comps1.size() > comps2.size() ? -1 : 1;
        }
        return res;
    }

}