JDBC Result set to Java HashMap

resultset_to_map.java

try {
    Class.forName(driver);
    Connection con = DriverManager.getConnection(url + db, user, pass);
    Statement stmt = con.createStatement();
    ResultSet rs = stmt.executeQuery(query);
    ResultSetMetaData rsmd = rs.getMetaData();
    List<String> columns = new ArrayList<String>(rsmd.getColumnCount());
    for(int i = 1; i <= rsmd.getColumnCount(); i++){
        columns.add(rsmd.getColumnName(i));
    }
    List<Map<String,Object>> data = new ArrayList<Map<String,Object>>();
    while(rs.next()){                
        Map<String,Object> row = new LinkedHashMap<String, Object>(columns.size());
        for(String col : columns) {
            row.put(col, rs.getString(col));
        }
        data.add(row);
    }
    System.out.println(data);
    rs.close();
    stmt.close();
    con.close();
} catch (Exception e) {
    System.out.println(e);
}