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4. AN IMPLEMENTATION 4.7. Generic to Original Syntax Converter
%m.LBra%a.name%m.RBra%n
..(other patterns)..
ServerType standalone
Listing 4.9: Example FStr
Listing 4.10: Apache parameter with a single value
Note that in the example, the FStr is assigned to the Engine block and not to the block
pattern. This happens because there are cases where the same pattern has different formats in
a configuration file language. For example, a parameter in an Apache configuration file might
have one (Listing 4.10) or multiple values (Listing 4.11), or an XML element might have one
(Listing 4.12) or multiple sub-elements (Listing 4.13), which leads to multiple format strings.
Therefore, FStr cannot be factorized in a single field, like Metadata.
4.7 Generic to Original Syntax Converter
The Generic to Original syntax Converter contains two classes, PrinterMain and Printer.
The first is used to interact with the user, while the second contains methods for the interpreta-
tion and printing of the file in generic syntax (i.e., XML). Following is a deeper explanation of
both classes.
The PrinterMain class implements a main method which receives the location of the XML
file in argument. It imports the XML document from the file to memory using the Java XML
parsing API. Then, PrinterMain sends the document pointer and a stream to the Printer and
the latter prints the final configuration file in original syntax to the stream in argument.
The Printer class manages the printing of XML elements inside an XML file. It implements
a single visible method, print.
The print method is called by PrinterMain to print the entire XML document into a con-
figuration file in its original syntax. It receives a stream and a NodeList object as arguments.
NodeList refers to a DOM interface for the representation of lists of Node objects, whereas
each Node object stands for XML components, such as elements, attributes or text nodes. Since
the XML standard defines XML documents as having a single root node, PrinterMain calls
Listing 4.11: Apache parameter with multiple values
DirectoryIndex index.html index.htm index.shtml
default.htm default.html index.php
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