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3. AN APPLICATION RECONFIGURATION FRAMEWORK 3.3. Original to Generic syntax Converter
Presentation Layer
User
Interface
Logical Layer
Configuration
File Parser
Storage Layer
Parser
Repository
Code
Generator
Presentation Layer
Logical Layer
Storage Layer
Figure 3.4: Interactions on the successful file recognition scenario
2. The Configuration File Parser gets the parsers from the Parser Repository
and tests the configuration file with all of them. By assumption, at least one parser is
able to parse the configuration file entirely, therefore, at least one valid AST for the entire
configuration file is produced;
3. The Configuration File Parser sends the generated ASTs to the Code Generator
and returns User Interface the generic syntax of the file for each parser;
4. Finally, the User Interface chooses a valid file in generic syntax and stores it to disk.
On the other hand, if a configuration file is new to the tool, the process requires more com-
ponents to operate. The previous process is performed normally until step 2, where no parser
was found to be able to parse the configuration file by the User Interface. Afterwards, the
action flow is as follows:
1. The user must build a grammar through the User Interface so that the Grammar
Compiler generates a parser from it. If a grammar declaration is not valid or if the
generated parser still cannot parse the configuration file, another grammar must be built
until the configuration file is parsed;
2. Meanwhile, every grammar produced by the user is stored in the Tentative Grammar
Repository for the user to easily rollback any change made to a grammar;
3. When a parser successfully recognizes a configuration file, the user has the last word as
he may approve or disapprove the structure produced by that parser;
4. If the user does not approve of a parser, another one must naturally be generated;
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