if (mtdt == null) {            mtdt = conn.getMetaData();        }        String[][] s = getAllResultSetColumns(mtdt.getPrimaryKeys(catalog,                null, table));        mtdt = null;        return s;    }    public String[][] getTableImportedKeys(String catalog, String table) throws Exception {        if (mtdt == null) {            mtdt = conn.getMetaData();        }        String[][] s = getAllResultSetColumns(mtdt.getImportedKeys(catalog,                null, table));        mtdt = null;        return s;    }    public String[][] getTableExportedKeys(String catalog, String table) throws Exception {        if (mtdt == null) {            mtdt = conn.getMetaData();        }        String[][] s = getAllResultSetColumns(mtdt.getExportedKeys(catalog,                null, table));        mtdt = null;        return s;    }    public String[] getProcedures(String catalog) throws Exception {        if (mtdt == null) {            mtdt = conn.getMetaData();        }        String[] s = getResultSetColumn(mtdt.getProcedures(catalog, null, "%"), "PROCEDURE_NAME");        mtdt = null;        return s;    }    public String[][] getProcedureColumns(String catalog, String            procedure) throws Exception {        if (mtdt == null) {            mtdt = conn.getMetaData();        }        String[][] s = getAllResultSetColumns(mtdt.getProcedureColumns(catalog, null, procedure, "%"));        mtdt = null;        return s;    }    public void test() throws Exception {        String text = toString2(getSession()) +                toString2(getEngineInfo()) +                toString2(getEngineSpecs()) +                toString2(getEngineFeatures()) +                toString2(getEngineLimitations());        System.out.println("-> METADATAS\n" + text);        String[] catalogs = getCatalogs();        System.out.println("-> CATALOGS\n" + toString1(catalogs));        for (int i = 0; i < catalogs.length; i++) {            System.out.println("-> USER TABLES IN " + catalogs[i]);            System.out.println(toString1(getTables(catalogs[i], "TABLE")));        }        for (int i = 0; i < catalogs.length; i++) {            System.out.println("-> SYSTEM TABLES IN " + catalogs[i]);            System.out.println(toString1(getTables(catalogs[i], "SYSTEM TABLE")));        }        System.out.println(toString2(getAllResultSetColumns(getResultSet("SELECT* FROM TEST"))));        System.out.println("OK");    }    //************************************************************************    //************************************************************************    //************************************************************************    public String[] getResultSetColumn(ResultSet rs, String column) throws Exception {        Vector v = new Vector();        while (rs.next()) {            v.addElement(rs.getString(column));        }        String s[] = new String[v.size()];        s = v2a(v);        return s;    }    public String[] getResultSetColumn(ResultSet rs, int i) throws Exception {        Vector v = new Vector();        while (rs.next()) {            v.addElement(rs.getString(i));        }        String s[] = new String[v.size()];        s = v2a(v);        return s;    }    public ResultSet getResultSet(String sql) throws Exception {        Statement st = conn.createStatement();        st.setMaxRows(400);        System.out.println(sql);        return st.executeQuery(sql);    }    public void executeUpdate(String sql) throws Exception {        Statement st = conn.createStatement();        System.out.println(sql);        st.executeUpdate(sql);        //return st.executeQuery(sql);    }    public ResultSet getSrollResultSet(String sql) throws Exception {        Statement st = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);        st.setMaxRows(400);        System.out.println(sql);        return st.executeQuery(sql);    }    public String[][] executeComplexQuery(String sql) throws Exception {        boolean resultSetIsAvailable;        boolean moreResultsAvailable;        int i = 0;        int res = 0;        String[][] bigresult = null;        String[][] result = null;        Statement curStmt = conn.createStatement();        resultSetIsAvailable = curStmt.execute(sql);        ResultSet rs = null;        for (moreResultsAvailable = true; moreResultsAvailable;) {            if (resultSetIsAvailable) {                if ((rs = curStmt.getResultSet()) != null) {                    // we have a resultset                    result = getAllResultSetColumns(rs);                }            } else {                if ((res = curStmt.getUpdateCount()) != -1) {                    // we have an updatecount                    result = new String[2][2];                    result[0] = setString2("UPDATE", "");                    result[1] = setString2("Update count", res);                } else {                    // else no more results                    moreResultsAvailable = false;                }            }            if (moreResultsAvailable) {                resultSetIsAvailable = curStmt.getMoreResults();            }            bigresult = concat(bigresult, result);        }        if (rs != null) rs.close();        curStmt.close();        return bigresult;    }    public String[][] getAllResultSetColumns(ResultSet rs) throws Exception {        String[] headers = getResultSetColumnHeaders(rs);        String[][] rows = getResultSetRows(rs);        String[][] t = new String[rows.length + 1][headers.length];        t[0] = headers;        for (int i = 0; i < rows.length; i++) {            t[i + 1] = rows[i];        }        return t;    }    public String[] getResultSetColumnHeaders(ResultSet rs) throws Exception {        ResultSetMetaData rsmd = rs.getMetaData();        String[] headers = new String[rsmd.getColumnCount()];        for (int i = 0; i < headers.length; i++) {            headers[i] = rsmd.getColumnLabel(i + 1);        }        return headers;    }    public String[][] getResultSetRows(ResultSet rs) throws Exception {        ResultSetMetaData rsmd = rs.getMetaData();        Vector v = new Vector();        while (rs.next()) {            String[] columns = new String[rsmd.getColumnCount()];            for (int i = 0; i < columns.length; i++) {                columns[i] = rs.getString(i + 1);            }            v.addElement(columns);        }        String[][] t = new String[v.size()][rsmd.getColumnCount()];        for (int i = 0; i < v.size(); i++) {            t[i] = (String[]) v.elementAt(i);        }        rs.close();        return t;    }    public String[] setString2(String s, String t) {        String[] r = new String[2];        r[0] = new String(s);        r[1] = new String(t);        return r;    }    public String[] setString2(String s, boolean b) {        String[] r = new String[2];        r[0] = new String(s);        r[1] = new String(b ? "yes" : "no");        return r;    }    public String[] setString2(String s, int i) {        String[] r = new String[2];        r[0] = new String(s);        r[1] = "" + i;        return r;    }    public String toString1(String[] s1) {        String s = "\n";        for (int i = 0; i < s1.length; i++) {            s += s1[i] + "\n";        }        return s;    }    public String toString2(String[][] s2) {        String s = "\n";        for (int i = 0; i < s2.length; i++) {            for (int j = 0; j < s2[0].length; j++) {                s += s2[i][j] + "\t";            }            s += "\n";        }        return s;    }    public String[] v2a(Vector v) {        String[] s = new String[v.size()];        for (int i = 0; i < v.size(); i++) {            s[i] = (String) v.elementAt(i);        }        return s;    }    public String[][] concat(String[][] a, String[][] b) {        if (a == null) return b;        if (b == null) return a;        String[][] out = new String[a.length + b.length][Math.max(a[0].length, b[0].length)];        for (int i = 0; i < a.length; i++) {            out[i] = a[i];        }        for (int j = 0; j < b.length; j++) {            out[a.length + j] = b[j];        }        return out;    }}