Mark's criteriaString builder
Anonymous
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Posts: 18944
posted 15 years ago
Mark had this to say in the huge Connection lock/unlock thread (which was a very good read BTW):
"The points I lost was because I added two methods to the Data class that should have been in the CriteriaFindBuilder class..."
Glad I saw this. I've got
public String getFormattedCriteriaString(
String[][] fieldsAndValues) in Data. Was patting self on back til I saw Mark's post.
Question is: doesn't this method have a good home in Data? Data requires this format, and so should offer this formatting service.
Also, what were your string builder methods, Mark? Is there a more eloquent way to provide raw info to a string builder method than a 2-level array?
p.s. started coding the assignment in earnest just last week and have come to LOVE this site!
"The points I lost was because I added two methods to the Data class that should have been in the CriteriaFindBuilder class..."
Glad I saw this. I've got
public String getFormattedCriteriaString(
String[][] fieldsAndValues) in Data. Was patting self on back til I saw Mark's post.
Question is: doesn't this method have a good home in Data? Data requires this format, and so should offer this formatting service.
Also, what were your string builder methods, Mark? Is there a more eloquent way to provide raw info to a string builder method than a 2-level array?
p.s. started coding the assignment in earnest just last week and have come to LOVE this site!
Sai Prasad
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John Smith
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posted 15 years ago
I think I can answer for Mark (he is on vacation to Mumbai 
), -- each class should focus on the specific purpose. The criteria building (parsing, storing the key-value entries in some data structure, etc) have nothing to do with Data, whose purpose is to describe Data. But since we need the criteriaFind() implemented in data, the criteria building functionality should be isolated in a helper class.
Eugene Kononov.
), -- each class should focus on the specific purpose. The criteria building (parsing, storing the key-value entries in some data structure, etc) have nothing to do with Data, whose purpose is to describe Data. But since we need the criteriaFind() implemented in data, the criteria building functionality should be isolated in a helper class.Eugene Kononov.
Anonymous
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Matthew Comer
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posted 15 years ago
The GRASP patterns say something about this - your are looking for HIGH cohesiveness and LOOSE coupling. So, the functions provided by a class should be HIGHLY COHESIVE, i.e. related to a single purpose or objective and LOOSELY COUPLED to other classes.
So, the question is this: What does the parsing of query criteria have to do with the maintenance of a flat file database? Well, not much. To build both of these behaviors into a single class would NOT lead to high cohesion within the class.
It is important to note though that putting this behavior in a seperate class should be done in such a way as to keep COUPLING LOW, i.e. don't design CriteriaBuilder in such a way that it is highly dependant on the internal implementation or data structures of the Data class.
Matt
So, the question is this: What does the parsing of query criteria have to do with the maintenance of a flat file database? Well, not much. To build both of these behaviors into a single class would NOT lead to high cohesion within the class.
It is important to note though that putting this behavior in a seperate class should be done in such a way as to keep COUPLING LOW, i.e. don't design CriteriaBuilder in such a way that it is highly dependant on the internal implementation or data structures of the Data class.
Matt
Arup Chowdhury
Greenhorn
Posts: 10
posted 15 years ago
CriteriaBuilder/Finder method will be using some kind of an Algorithmn. Instead of directly putting the algoritmn in the Data class, I have created a criteriaFinder class to the work.
Advantages is loose coupling between the Data class and the Algorithm used, and also ability to add and remove algorithms.
This is a combination of Functor Pattern and Strategy Pattern
Regards
Arup
Advantages is loose coupling between the Data class and the Algorithm used, and also ability to add and remove algorithms.
This is a combination of Functor Pattern and Strategy Pattern
Regards
Arup
Anonymous
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John Smith
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Anonymous
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