AppVersion.java

package com.mattc.autotyper;

/**
 * Extremely Simple Application Version Comparison
 */
public final class AppVersion {

    private AppVersion() {
        // DO NOT INSTANTIATE
    }

    public static final int MAJOR, MINOR, REVISION;

    static {
        try {
            final String[] parts = Ref.VERSION.split("\\.");
            MAJOR = parts.length < 1 ? 0 : Integer.parseInt(parts[0]);
            MINOR = parts.length < 2 ? 0 : Integer.parseInt(parts[1]);
            REVISION = parts.length < 3 ? 0 : Integer.parseInt(parts[2]);
        } catch (final Throwable t) {
            throw new ExceptionInInitializerError(t);
        }
    }

    public static boolean isEqual(int major, int minor, int revision) {
        return (MAJOR == major) && (MINOR == minor) && (REVISION == revision);
    }

    public static boolean isHigher(int major, int minor, int revision) {
        return isHigherOrEqualTo(major, minor, revision + 1);
    }

    public static boolean isHigherOrEqualTo(int major, int minor, int revision) {
        if (MAJOR != major)
            return major < MAJOR;
        else if (MINOR != minor) return minor < MINOR;

        return REVISION >= revision;
    }

    public static boolean isLower(int major, int minor, int revision) {
        return isLowerOrEqualTo(major, minor, revision - 1);
    }

    public static boolean isLowerOrEqualTo(int major, int minor, int revision) {
        if (MAJOR != major)
            return major > MAJOR;
        else if (MINOR != minor) return minor > MINOR;

        return REVISION <= revision;
    }

    public static boolean isEqualTo(int major, int minor, int revision) {
        return MAJOR == major && MINOR == minor && REVISION == revision;
    }

    public static int compareTo(String version) {
        String[] parts = version.split("\\.");
        int major = Integer.parseInt(parts[0]);
        int minor = Integer.parseInt(parts[1]);
        int revision = Integer.parseInt(parts[2]);

        if (isLower(major, minor, revision))
            return -1;
        else if (isHigher(major, minor, revision))
            return 1;
        else
            return 0;
    }

}