Question

I have a method :

public void dbQuery(String query, String what) {
    try {
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery(query);

        if(what.equals("temp_table")) {
            String temporary_table = rs.getString("table_name_temp");
            System.out.println(temporary_table);
            return;
        }

        }

    catch (Exception e) {
        e.printStackTrace();
        }

    finally {
        if (rs != null) rs.close();
        if (stmt != null) stmt.close();
        }

}



String query = "EXEC temptables.dbo.create_temp_cdr 'SIP'";
String temporary_table = db.dbQuery(query,"temp_table");

How do I get the return of a void to use it in another db.dbQuery() ?

PS : I need a value from dbQuery() so I can construct another query to call dbQuery() again

Answer 1

You can either have your method not be void, and have a return type, then you can have the line

return temporary_table;

which would return the temporary_table variable.

Another way would be to pass by reference to the method. For example, you can pass a StringBuilder object to the method. Any changes to this object in the method will then also apply after the method has returned.

public void addToString(StringBuilder query, String toAdd) {
    query.append(toAdd);
}

A call to this method of

StringBuilder query = new StringBuilder("start");
System.out.println(query.toString());
addToString(query, "end");
System.out.println(query.toString());

would have the output of:

start
startend