有时候需要对安卓版本号排序，在此记录一下。
话不多说，先上代码：

public static void main(String[] args) {
        long begin = System.currentTimeMillis();
        List<String> list = new ArrayList<>();
        list.add("Android7");
        list.add("Android2");
        list.add("Android2.1");
        list.add("Android4");
        list.add("Android3");
        list.add("Android5");
        list.add("Android6");
        list.add("Android6.1");
        list.add("Android6.2");
        list.add("Android10");
        list.add("Android10.1");
        list.add("Android11.2");
        list.add("Android3.1.2");
        list.add("Android7.2.3");
        list.add("Android3.2");
        Collections.sort(list, (o1, o2) -> {

            int[] var1 = getVersionArray(o1.substring(7));
            int[] var2 = getVersionArray(o2.substring(7));
            int lim = Math.min(var1.length, var2.length);
            int k = 0;
            while (k < lim) {
                if (var1[k] == var2[k]) {
                    k++;
                    continue;
                }
                return var1[k] - var2[k];
            }
            if (var1.length == var2.length) {
                return 0;
            }
            return var1.length - var2.length;

        });
        list.forEach(System.out::println);
        long end = System.currentTimeMillis();
        System.out.println("排序耗时:" + (end - begin) + "ms");

    }

    public static int[] getVersionArray(String version) {
        String[] array = version.split("\\.");
        int[] varray = new int[array.length];
        int k = 0;
        while (k < array.length) {
            varray[k] = Integer.parseInt(array[k]);
            k++;
        }
        return varray;
    }

这是一开始的代码，但并不适用于包含比如Android8.a 、Android8.c，带有字符串的版本号。改进一下，适用所有版本号的排序:

public static void main(String[] args) {
        long begin = System.currentTimeMillis();
        List<String> list = new ArrayList<>();
        list.add("Android7");
        list.add("Android2");
        list.add("Android2.1");
        list.add("Android4");
        list.add("Android3");
        list.add("Android5");
        list.add("Android6");
        list.add("Android6.1");
        list.add("Android6.2");
        list.add("Android10");
        list.add("Android10.1");
        list.add("Android11.2");
        list.add("Android3.1.2");
        list.add("Android7.2.3");
        list.add("Android3.2");
        list.add("Android8.a");
        list.add("Android8.c");
        list.add("Android1.2.a");
        Collections.sort(list, (o1, o2) -> {
            String version1 = o1.substring(7);
            String version2 = o2.substring(7);
            return compareVersion(version1, version2);

        });
        list.forEach(System.out::println);
        long end = System.currentTimeMillis();
        System.out.println("排序耗时:" + (end - begin) + "ms");

    }

    public static int compareVersion(String version1, String version2) {
        String[] version1Array = version1.split("\\.");
        String[] version2Array = version2.split("\\.");
        int lim = Math.min(version1Array.length, version2Array.length);
        int index;
        int diff = 0;
        for (index = 0; index < lim; index++) {
            //先比较字符长度，比如6,10
            diff = version1Array[index].length() - version2Array[index].length();
            if (diff != 0) {
                break;
            }
            //长度一样，再比较字符
            diff = version1Array[index].compareTo(version2Array[index]);
            if (diff != 0) {
                break;
            }
        }
        //此时若还未区分出大小，则比较版本号的长度，看是否有子版本
        diff = (diff != 0) ? diff : version1Array.length - version2Array.length;
        return diff;
    }

最终排序结果如下，最终是我们想要的效果：

image.png