Automatizar selects con DatabaseMetaData

esta es la parte del código en Model.java, lo que respectan los select automatizados:

public String select(String[] cols, String[][] tables, String[][] where,String[] group,String[][] having,String[][] order){
        String Consulta = "select ";
        if(cols == null){
            Consulta += "* ";
        } else {
            Consulta += this.createColumns(cols, tables);
        }
        LinkedList<String[]> tab = this.prepareTables(tables);
        Consulta += this.createFrom(tab);
        if(where != null){
            Consulta += " " + this.createConditions(tab,where);
        }
        if(group != null){
            Consulta += " " + this.createGroup(tab,group);
        }
        if(having != null){
            Consulta += " " + this.createHaving(tab,having);
        }
        if(order != null){
            Consulta += " " + this.createOrder(tab,order);
        }
        return Consulta;
    }
    private LinkedList<String[]> prepareTables(String[][] tables){
        LinkedList<String[]> tab = new LinkedList();
        String[] temp = { this.generateKey(tab, this.getTable()), this.getTable(),null};
        tab.add(temp);
        if(tables != null){
            for (String[] table : tables) {
                String[] temp2 = {this.generateKey(tab, table[0]), table[0], table[1]};
                tab.add(temp2);
            }
        }
        return tab;
    }
    private String generateKey(LinkedList<String[]> alias,String now){
        String d = "" + now.charAt(0);
        if(alias.isEmpty()){
            return d;
        } else {
            for (String[] alia : alias) {
                for (int x = 0; x < now.length(); x++) {
                    if (alia[0].equals(d)) {
                        x++;
                        d += now.charAt(x);
                    }
                }
            }
            return d;
        }
    }
    private String createColumns(String[] cols,String[][] tables){
        String columns = "";
        for(String c : cols){
            if(tables == null){
                columns += c;
            } else {
                LinkedList<String[]> tab = this.prepareTables(tables);
                for (String[] tab1 : tab) {
                    LinkedList<String> temp = this.objbd.getColumns(tab1[1]);
                    for (String c1 : temp) {
                        if (c1.equals(c)) {
                            columns += tab1[0] + "." + c;
                        }
                    }
                }
            }
            if(!cols[cols.length -1].equals(c)){
                columns += ",";
            } else {
                columns += " ";
            }
        }
        return columns;
    }
    private String createFrom(LinkedList<String[]> tables){
        String from = "from " + tables.getFirst()[1] + " " + tables.getFirst()[0] + " ";
        for(int i = 1; i < tables.size(); i++){
            from += tables.get(i)[2] + " join " + tables.get(i)[1] + " " + tables.get(i)[0] + " on";
            from += this.createCombos(
                new String[]{tables.get(i)[0],tables.get(i)[1]},
                new String[]{tables.get(i-1)[0],tables.get(i-1)[1]}
            );
            if(!tables.getLast()[1].equals(tables.get(i)[1])){
                from += " ";
            }
        }
        return from;
    }
    private String createCombos(String[] emisor, String[] receptor){
        String combo = " ";
        LinkedList<String> keys = this.objbd.getPrimaryKeys(emisor[1]);
        LinkedList<String> fays = this.objbd.getForeignKeys(receptor[1]);
        for(String f : fays){
            for(String k : keys){
                if(k.equals(f)){
                    combo += receptor[0] +"."+k +" = "+ emisor[0] +"."+f;
                    break;
                }
            }
        }
        return combo;
    }

    private String createConditions(LinkedList<String[]> tables, String[][] where){
        String condition = "where ";
        for (String[] where1 : where) {
            for (String[] table : tables) {
                LinkedList<String> temp = this.objbd.getColumns(table[1]);
                for (String c1 : temp) {
                    if (c1.equals(where1[0])) {
                        where1[0] = table[0] + "." + where1[0];
                    }
                }
            }
        }
        for (String[] where1 : where) {
            if (where1[1].equals("between") || where1[1].equals("not between")) {
                condition += where1[0] + " " + where1[1] + " ? and ?";
            } else if (where1[1].equals("not null") || where1[1].equals("null")) {
                condition += where1[0] + " " + where1[1];
            } else {
                condition += where1[0] + " " + where1[1] + " ?";
            }
            if (!where[where.length -1][0].equals(where1[0])) {
                condition += " " + where1[2] + " ";
            }
        }
        return condition;
    }
    private String createGroup(LinkedList<String[]> tables,String[] group){
        String groupby = "group by ";
        for (int i= 0; i< group.length; i++) {
            for (String[] table : tables) {
                LinkedList<String> temp = this.objbd.getColumns(table[1]);
                for (String c1 : temp) {
                    if (c1.equals(group[i])) {
                        group[i] = table[0] + "." + group[i];
                    }
                }
            }
        }
        for (String group1 : group) {
            groupby += group1;
            if(!group[group.length -1].equals(group1)){
                groupby += ",";
            }
        }
        return groupby;
    }
    private String createHaving(LinkedList<String[]> tables,String[][] having){
        String hav = "having ";
        return hav;
    }
    private String createOrder(LinkedList<String[]> tables,String[][] order){
        String orderby = "order by ";
        for (String[] order1 : order) {
            for (String[] table : tables) {
                LinkedList<String> temp = this.objbd.getColumns(table[1]);
                for (String c1 : temp) {
                    if (c1.equals(order1[0])) {
                        order1[0] = table[0] + "." + order1[0];
                    }
                }
            }
        }
        for (String[] order1 : order) {
            orderby += order1[0] + " " + order1[1];
            if(!order[order.length -1][0].equals(order1[0])){
                orderby += ",";
            }
        }
        return orderby;
    }

pero no sé cómo armar los parámetros del array en el having, en el main:

//ejemplo para el having
        System.out.println("");
        System.out.println(new CompradorModel().select(
            new String[]{"usuCI","usuNom1"},
            new String[][]{{"usuarios","left"},{"roles","inner"}},
            new String[][]{{"usuCI","like","and"},{"usuFecNac","between"}},
            new String[]{"usuCI"},
            null,
            new String[][]{{"usuCI","asc"},{"usuFecNac","desc"}}
        ));

Me falta pulir bien el tema de los havings automatizados, las serias subconsultas xq no sé cómo hacerlo, necesitaría una idea de cómo hacerlas automatizadas, y me falta pulir el createColumns en caso de renombrar campos y también si quiero usar funciones agregadas.