Data Conversion Design Patters

Question

I'm looking at building a conversion program that will import data from several different formats and convert into one common format. The convertor should simply be pointed to a database or a flat-file and it will extract the data and populate tables in the target database. All the logic is mind-numbingly simple, but as far as an overall design, what are your thoughts?
For example, should I build a separate tool that does validation of source data? Or should the validator be part of the convertor?
Are there design patterns out there that anyone can recommend?

Answer 1

This problem u can go for strategy pattern. A strategy is nothing but an algorithm to reach the soution.
Strategy pattern deals with different algorithms(strategies) to achieve the same result.The client will have some indicator. Using the indicator, stategy manager will decide which algorithm to invoke.
In ur case,the algorithm may differ depending on the data format. For (eg) if you have five different formats of data , then you may have to write five different type of logic to achieve the solution.
So firt of all u need to identify the strategies u r going to use.
Now you may require following classes
1) SourceReader -- > this class is responsible for getting the data either from file/database.It just reads and holds data.
It identifies which strategy to use by parsing the data . No data processing happens here
2) StrategyManager --> Strategy manager is the one who reads the data from source reader and decides and instantiate the strategy to use.
3) Strategy --> It could be an interface or an abstract class. It can be decided upon any common operation involved irrespective of data           format.
4)ConcreateStrategy --> This implemenattion class, here actual data extraction process will happens.
5) DataLoader --> this calss loads the data in to the destination database
6) YurEntity --> The data to be populated can be kept in the form object. if ur object contains many attributes, we can have data in the           form objects. (this class is required only if all the data are realted and fall in to same logical group).
Class SourceReader{
Vector data;
public void do(){
readData()
StrategyManager.getInstance().process(data,findStrategy());
public void readData()
     read from file or db and populate data
public int findStrategy()
     logic for identifying format
class StrategyManager
public static StrategyManager sm = new StrategyManger();
public StrategyManager getInstance()
return sm;
public void process(Vector data,int indicator)
     //read the indicator and instantiate the appropriate startegy class
     Strategy s = new Strategy1();
     s.process();
abstract class strategy{
public abstract void parse();
public void validate{};// if the validation logic is common, u can have implemenation here itself.
public updateDB()
     update destination db;
public void process()
     validate();
     parse();
     updateDB();
}