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4. AN IMPLEMENTATION 4.5. Original to Generic syntax Converter
interface CompilationData {
boolean wasCompiled();
String getErrorMessage();
String getParserLocation();
}
Listing 4.7: CompilationData data structure
method. If the compilation ended without any occurred error, the parser location is given by
the getParserLocation method. Alternatively, if an error ocurred during the compilation,
it is accessible through the getErrorMessage method.
4.5 Original to Generic syntax Converter
After the components required in the Original to Generic syntax Converter were identified and
the behaviour of each one was described, their implementation took place. Following is shown
how the components identified in Section 3.3 were implemented.
4.5.1 User Interface
The User Interface is passed multiple configuration file locations upon its invocation by
the user. The parsing of multiple configuration files is sequential, or, in other words, UI config-
ures one file at a time and only when that file is configured should the next file configuration
start.
To configure a file, UI sends its location to the Configuration File Parser in order
to parse it with every available parser. The Configuration File Parser returns a map of
ParsingData objects which tells if the parsing was successful with any parser, as well as the
percentage of parsed file, the parsed file blocks in generic syntax and the position of the first
and last characters of the corresponding block.
When a file is successfully parsed, the corresponding AST is sent to Code Generator and
the returned file in XML is placed in a temporary file folder, with the same name as the original
configuration file, plus the suffix “.xml”.
If a file was not entirely parsed, UI displays the parts of the file which were recognized
by the parser with the best configuration file parse percentage and the grammar used on the
respective parser. Then, UI prompts the user for a file containing a grammar to be com-
piled and sends the grammar to Grammar Compiler. The Grammar Compiler returns a
CompilationData object which tells whether there was any error compiling the grammar. If
an error ocurred, the user must alter the grammar in the file to correct the error(s) and then
trigger another grammar compilation until the grammar is successfully compiled.
When a grammar is successfully compiled, UI attempts to parse the configuration file
with the newly generated parser by invoking the Configuration File Parser’s doParse
method which tests a file with a single parser. If the file was still not entirely recognized, the
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