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    <p>I would code the "Operations" you do as objects. You have the data, when you apply an operation to it, that operation is an object. the operation object holds some information of it's own (Perhaps a starting and ending value) and it knows how to format that value for output.</p> <p>When you start, you a queue of these operations--each one slightly different (possibly different classes, possibly just with internal state differences when they are created). You combine this queue with your data and pass the data from one piece in the queue to the next, or you can think of it as iterating over the queue and applying each operation to the data (which you probably pass in).</p> <p>When you are done, the operation objects each remember the history of what they did and know how to format it (for instance, "deducted %s percent for tax") and your data has been mutated to the correct value.</p> <p>This can also give you "Unwinds" where you could apply the pattern in the reverse order to back up to a previous value (Which probably has no interest to you here, but in some cases can be amazing).</p> <p>I believe this is called the "Command" pattern. It's terribly useful in any case.</p> <p>The other nice thing--the group of operations you place into the queue can be selected with data or any number of sources allowing you to adjust your calculations without any code changes in many cases.</p> <p>The classes would be terribly simple, something like:</p> <pre> public class TaxOperation { private double rate; private double amountTaxed; public TaxOperation(double rate) { this.rate=rate; } @Override public double getValue(double initial) { amountTaxed = initial * rate; return initial - amountTaxed; } @Override public String getDescription() { return "A tax of "+rate+" was applied which deducted "+amountTaxed } } </pre> <p>This seems really simple, and it is, but sometimes the simple classes do the most. Obviously the getValue operation isn't what you want, but you should be able to see how to derive what you want using that pattern.</p> <p>Also note that an "Operation" can do anything--for instance it can be amazingly good for threading (Imagine your operations take seconds or minutes, you just submit a queue of them to a processor and let them go).</p>
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    1. PODesign Pattern to track partial results of a complex process
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    1. COThanks for the comment, it's really useful and inspiring. Now I have some doubts abouts how to save the partial results if I use this pattern, I've updated the questions with more details about this. Thanks!
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    2. COYou can just persist the set of objects in the "Queue" directly--either to a database or serialized to a file. If you are separating them from the original data, you may want to store more information internally like the "Start" and "End" values just for tracking. The start/end values could be stored in an abstract base class of "Operation" to hide some redundant code.
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    3. COI don't understand your idea. Also, the requirements of the organization are that I have to use a relational database. Also, the application use hibernate as orm to map the entities to the database.
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