Retrieve Database Tables?

Question

I am building a JTree from my database. The first node is the Database, the table names as subnodes, and the column names as subnodes for each table. The problem, is that I don't understand the architecture for retrieving the table names. This is what I would like to happen:
        try {
            Class.forName(className);
            Connection conn = DriverManager.getConnection(URL + options,username,password);
            String dbName = conn.getCatalog();
            DefaultMutableTreeNode top = new DefaultMutableTreeNode(dbName);
            tree = new JTree(top);
            DatabaseMetaData dmd = conn.getMetaData();
            ResultSet rs = dmd.  //return Tables
            ResultSetMetaData rsmd = rs.getMetaData();
            int tableCount = rsmd. //getTableCount();
            String[] tableNames = new String[tableCount];
            DefaultMutableTreeNode category = null;
            for(int i=0;i<tableCount;i++){
                tableNames=rsmd. //getTableName(i+1);
category = new DefaultMutableTreeNode(tableNames[i]);
top.add(category);
conn.close();
I know there is a ResultSet as follows: DatabaseMetaData dmd = conn.getMetaData();
ResultSet rs = dmd.getTables(String catalog, String schemaPattern, String tableNamePattern, String[] types) But I don't understand this and would appreciate some clarification.
Thanks

Answer 1

Different DBMS softwares provide different ways to retrive meta data.
I cant give you specific information unless you tell us what is the DBMS software that you want to access.
If you want to write a genaric tool to work with all the DBMSs you will have to write different logic for different softwares and some time for different versions of same software.
Ex:- MySQL changed its meta data providing method in version 5