Method main

src/test/java/test_JXTpp_Lmax.java:31–117

(String[] args)

    private static String K_c = "6574b33984e7fb55";

    public static void main(String[] args) {
        //Step 1 prepare the parameters
        //the number of attributes which aren't the join attribute in the table.
        int key_colnum = 9;
        //the number join attributes in the table.
        int join_column = 1;
        int record_num = (int) Math.pow(2, 16);
        int table_num = 2;//the number of the queried tables
        String condition = "_Lmax100";//the condition aims to choose different tables from dataset
        int[][] l_max = new int[table_num][join_column];
        String[] keyword = new String[table_num];
        String[] join_attr = new String[table_num];
        //Step 2 begin to set up
        System.out.println("---------------- JXT++ for different L_max -----------------");
        Setup_JXTpp[] table = new Setup_JXTpp[table_num];
        Map<BigInteger, ArrayList<byte[]>> tset = new LinkedHashMap<>();
        for (int i = 0; i < table_num; i++) {
            table[i] = new Setup_JXTpp(i + 1, key_colnum, join_column, record_num, condition);
            table[i].construct();
            tset.putAll(table[i].getTset());
            System.arraycopy(table[i].getL_max(), 0, l_max[i], 0, join_column);
        }
        System.out.println("L_max for table1 for the join attribute : " + Arrays.toString(l_max[0]));
        System.out.println("L_max for table2 for the join attribute : " + Arrays.toString(l_max[1]));

        //Step 3 begin to search

        //query 10 join attributes which indicates different L_max {100, 200, 300, 400, 500, 600, 700, 800, 900, 1000}.
        for (int v = 100; v <= 1000; v += 100) {
            l_max[0][0] = v;
            l_max[1][0] = v;
            for (int i = 0; i < table_num; i++) {
                keyword[i] = "keyword0" + "table" + (i + 1) + "_keyword_0_0";
                join_attr[i] = "join-attr0";
            }
            System.out.println("--------- JXT++ search(L_max = " + l_max[0][0] + ") --------");
            long search_all = 0;
            for (int x = 0; x < 1000; x++) {//run 1000 times
                long search_start = System.nanoTime();
                //Step 3.1 compute the stag
                BigInteger stag1 = new BigInteger(Hash.Get_SHA_256((K_token + keyword[0] + join_attr[0] + 1).getBytes(StandardCharsets.UTF_8)));
                Server_JXTpp serverMMJXTpp = new Server_JXTpp(tset, table, stag1);
                byte[] w_0 = Hash.Get_SHA_256((K_w + keyword[0]).getBytes(StandardCharsets.UTF_8));
                Map<Integer, byte[]> map_cnt = new LinkedHashMap<>();
                ArrayList<byte[][]> join_tokens = new ArrayList<>();
                for (int i = 0; i < table_num; i++) {//Step 3.2 compute the joinTokens
                    byte[] w_i = Hash.Get_SHA_256((K_wp + keyword[i]).getBytes(StandardCharsets.UTF_8));
                    byte[] join_hash = Hash.Get_SHA_256((K_h + join_attr[i]).getBytes(StandardCharsets.UTF_8));
                    byte[][] join_token = new byte[l_max[i][0]][];
                    for (int j = 1; j <= l_max[i][0]; j++) {
                        byte[] cnt;
                        if (map_cnt.containsKey(j)) {
                            cnt = map_cnt.get(j);
                        } else {
                            cnt = Hash.Get_SHA_256((K_c + j).getBytes(StandardCharsets.UTF_8));
                            map_cnt.put(j, cnt);
                        }
                        join_token[j - 1] = tool.Xor(tool.Xor(tool.Xor(w_0, w_i), join_hash), cnt);