Reuse static string array in Java / Inheritance like concept inside string array

Question

private static String[][] s1 = {
        { "a", "a1" },
        { "b", "b1" },
        { "c", "c1" },
        { "d", "d1" },
}

private static String[][] s2 = {
        { "c", "c1" },
        { "d", "d1" },
        { "e", "e1" },
        { "f", "f1" },
}

Here c,c1 and d,d1 is repeated in those string arrays. How to take that outside and put it in a common string array say s3, and s1 and s2 reuses/inherits it so that it need not be declared in two different places?

Answer 1

static String[] common = { "c", "c1" };

private static String[][] s1 = {
    { "a", "a1" },
    { "b", "b1" },
    common,
    { "d", "d1" }
}

private static String[][] s2 = {
    common,
    { "d", "d1" },
    { "e", "e1" },
    { "f", "f1" }
}

Works fine.

Answer 2

You can use ArrayList rather than String Array, since its very difficult to remove/insert elements if you use String array.

ArrayList<String[]> s1=new ArrayList<String[]>();
ArrayList<String[]> s2=new ArrayList<String[]>();

And use add() method to add all the elements, and scan the lists to find out the overlapped elements by using contains() method. Find that element and save&&remove it.