de.highbyte_le.weberknecht.Version.java Source code

Introduction

Here is the source code for de.highbyte_le.weberknecht.Version.java

Source

/*
 * Version.java
 *
 * Copyright 2007-2012 Patrick Mairif.
 * The program is distributed under the terms of the Apache License (ALv2).
 * 
 * created: 2007-09-01
 * tabstop=4, charset=UTF-8
 */
package de.highbyte_le.weberknecht;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Versions are denoted using a standard triplet of integers: MAJOR.MINOR.PATCH.
 * The basic intent is that MAJOR versions are incompatible, large-scale upgrades of the API.
 * MINOR versions retain source and binary compatibility with older minor versions,
 * and changes in the PATCH level are perfectly compatible, forwards and backwards.
 * 
 * @author pmairif
 */
public class Version {
    /**
     * Logger for this class
     */
    private final static Log logger = LogFactory.getLog(Version.class);

    private static Version appVersion = null;

    private final int major;
    private final int minor;
    private final int patch;

    /**
     * optional branch info
     */
    private final String branch;

    @SuppressWarnings("nls")
    public static synchronized Version getAppVersion() {
        if (null == appVersion) {
            try {
                InputStream in = Version.class.getResourceAsStream("version.properties"); //$NON-NLS-1$
                if (in != null) {
                    try {
                        Properties p = new Properties();
                        p.load(in);

                        appVersion = parseProperties(p);
                    } finally {
                        in.close();
                    }
                } else {
                    logger.error("getAppVersion() - version.properties not found");
                }
            } catch (IOException e) {
                logger.error("getAppVersion() - I/O Exception while loading version.properties: " + e.getMessage());
            }
        }

        return appVersion;
    }

    protected static Version parseProperties(Properties properties) {
        try {
            int major = Integer.parseInt(properties.getProperty("version.weberknecht.major"));
            int minor = Integer.parseInt(properties.getProperty("version.weberknecht.minor"));
            int patch = Integer.parseInt(properties.getProperty("version.weberknecht.patch"));
            String branch = properties.getProperty("version.weberknecht.branch");

            return new Version(major, minor, patch, branch);
        } catch (NumberFormatException e) {
            logger.error("parseProperties() - number format exception: " + e.getMessage());
        }

        return null;
    }

    public Version(int major, int minor, int patch) {
        this(major, minor, patch, null);
    }

    public Version(int major, int minor, int patch, String branch) {
        this.major = major;
        this.minor = minor;
        this.patch = patch;
        this.branch = branch;
    }

    public int getMajor() {
        return this.major;
    }

    public int getMinor() {
        return this.minor;
    }

    public int getPatch() {
        return this.patch;
    }

    public boolean hasBranch() {
        return (branch != null);
    }

    /**
     * @return the branch
     */
    public String getBranch() {
        return branch;
    }

    @Override
    public String toString() {
        return getVersionString(VersionFormat.FULL);
    }

    /**
     * create a version string
     */
    public String getVersionString(VersionFormat format) {
        StringBuilder b = new StringBuilder();

        b.append(major).append(".").append(minor); //$NON-NLS-1$

        if (format != VersionFormat.SHORT) {
            b.append(".").append(patch); //$NON-NLS-1$

            if (hasBranch())
                b.append("-").append(branch);
        }

        return b.toString();
    }

    public enum VersionFormat {
        /**
         * version string with just the major and minor number
         */
        SHORT,

        /**
         * version string with the full version information
         */
        FULL
    }
}