OOGenerator

Example0100_Encoding

G-2.0-plain_java-1.0 ⊰ Templates produce output. Such output might be just plain ASCII, plain Unicode or might be encoded somehow, say HTML. Furthermore, templates process input, which may or may not be written in the same encoding. And finally, the normal template text might have a third encoding. Let's assume you want to create a Java properties file based on XML input. Then - in the input we have '<', '>' and '&'. - in our template text we just want to write normal Unicode. - in the properties file everything non-ASCII (e.g. german umlauts) must be escaped '\uXXXX' In templates, such a situation is rather the rule then an exception. Instead of writing conversion calls each and everyplace, we just can use the recoding operator '⌘': ⊱… « String xml_input = " immer und überall gilt: 17 < 23 "; »… ◂xml_input⌘XML/JAVAPROP▸ ⊰ You get the output " immer und \u00FCberall gilt: 17 < 23 " The '⌘...' sequence is called a 'recoding'. It consists of a sequence of encoding names. The above example reads 'convert XML to JAVAPROP'. The encoding names are defined in an enumeration class named 'Encoding'. You can use this class also from normal Java code. If we have many such expressions in our template, we can define a default recoding: ⊱… ⊏ ⌘XML/JAVAPROP ⊐… ◂xml_input▸ ⊏ /⌘ ⊐… ⊰ This yields the same result as above. Default encodings can be nested (they apply to included and subtemplates, too, but we do not know yet what these are). ⊱… ⊏ ⌘DOCBOOK/JAVAPROP ⊐… ⋮⊏ ⌘XML/JAVAPROP ⊐… ◂xml_input▸ ⋮⊏ /⌘ ⊐… ⊏ /⌘ ⊐… ⊰ This again yields the same result as above. Encodings need not be complete, they will be combined. ⊱… ⊏ ⌘XML/ ⊐… ◂xml_input⌘/JAVAPROP▸ ⊏ /⌘ ⊐… ⊰ This again yields the same result as above. Note, that a default encoding applies to embedded Java expressions as well as normal template text. What if they are different, as within our example? Then you can apply a different default encoding to these categories. ⊱… ⊏ ⌘[x]XML/JAVAPROP ⊐… ⊏ ⌘[t]UTF8/JAVAPROP ⊐… ◂xml_input▸ This '<' is not translated, since we're here in normal template text, not in an expression. ◂"But this '<' is translated, since we're an expression"▸ ⊏ /⌘ ⊐… ⊏ /⌘ ⊐… ⊰ As you might have guessed, 'x' stands for 'expression' and 't' for 'template text'. ⊱…