StringUtils.java

package cm4mmupdater.utils;

import cm4mmupdater.misc.Log;

import java.util.ArrayList;
import java.util.Arrays;

public class StringUtils {
    private static final String TAG = "StringUtils";

    /**
     * Converts a String array to an String, joined by the Seperator
     *
     * @param items     The String Array to Join
     * @param seperator The Seperator used to join the String
     * @return The Joined String
     */
    public static String arrayToString(String[] items, String seperator) {
        if ((items == null) || (items.length == 0)) {
            return "";
        } else {
            StringBuffer buffer = new StringBuffer(items[0]);
            for (int i = 1; i < items.length; i++) {
                buffer.append(seperator);
                buffer.append(items[i]);
            }
            return buffer.toString();
        }
    }

    /**
     * Compare two versions.
     *
     * @param newVersion new version to be compared
     * @param oldVersion old version to be compared
     * @return true if newVersion is greater then oldVersion,
     *         false on exceptions or newVersion=oldVersion and newVersion is lower then oldVersion
     */
    public static boolean compareVersions(String newVersion, String oldVersion) {
        Log.i(TAG, "NewVersion: " + newVersion + ", oldVersion: " + oldVersion);
        if (newVersion.equals(oldVersion))
            return false;

        //Replace all - by . So a CyanogenMod-4.5.4-r2 will be a CyanogenMod.4.5.4.r2
        newVersion = newVersion.replaceAll("-", "\\.");
        oldVersion = oldVersion.replaceAll("-", "\\.");

        String[] sNewVersion = newVersion.split("\\.");
        String[] sOldVersion = oldVersion.split("\\.");

        ArrayList<String> newVersionArray = new ArrayList<String>();
        ArrayList<String> oldVersionArray = new ArrayList<String>();

        newVersionArray.addAll(Arrays.asList(sNewVersion));
        oldVersionArray.addAll(Arrays.asList(sOldVersion));

        //Make the 2 Arrays the Same size filling it with 0. So Version 2 compared to 2.1 will be 2.0 to 2.1
        if (newVersionArray.size() > oldVersionArray.size()) {
            int difference = newVersionArray.size() - oldVersionArray.size();
            for (int i = 0; i < difference; i++) {
                oldVersionArray.add("0");
            }
        } else {
            int difference = oldVersionArray.size() - newVersionArray.size();
            for (int i = 0; i < difference; i++) {
                newVersionArray.add("0");
            }
        }


        int i = 0;
        for (String s : newVersionArray) {
            String old = oldVersionArray.get(i);
            //First try an Int Compare, if its a string, make a string compare
            try {
                int newVer = Integer.parseInt(s);
                int oldVer = Integer.parseInt(old);
                if (newVer > oldVer)
                    return true;
                else if (newVer < oldVer)
                    return false;
                else
                    i++;
            }
            catch (Exception ex) {
                //If we reach here, we have to string compare cause the version contains strings
                int temp = s.compareToIgnoreCase(old);
                if (temp < 0)
                    return false;
                else if (temp > 0)
                    return true;
                else
                    //its the same value so continue
                    i++;
            }
        }
        //Its Bigger so return true
		return true;
	}
}