| home / experts / xml / column26 |
|
|
|
One building block for the RSSApplet is an XML parser to read
in the RSS file. The first versions of RSSApplet used Aelfred, a
fairly small Java XML parser. In an effort to shrink the applet size
even further I translated
Xparse from JavaScript to Java, and implemented
JSArray to mimic JavaScript arrays in Java. The result
is now released separately as Xparse-J, the initial version 1.0 is
a literal translation of Xparse 0.91, plus some Java-specific
adaptations.
The creator of Xparse, Jeremie, states that Xparse is a fully-compliant well-formed XML parser, with the exception of full error reporting, internal document type definitions, and related DTD functionality. I tend to think there is a bit more missing in terms of resolving external entities and especially handling Non-Unicode character sets.
com.exploringxml.xml,
the main parser class Xparse, the parsed document in
Nodes, and the utility class JSArray.
public class Xparse {
private String substring(String s, int start, int length) {
if (s.length() > start + length)
return s.substring(start, length);
else
return s.substring(start);
}
...
The substring function bridges one important
difference between Java and JavaScript: While JavaScript always
returns the rest of the string if the substring length exceeds
the string length, Java throws an IndexOutOfBoundsException.
The above code snippet implements the JavaScript behavior in Java.
I included this in Xparse because subclassing
java.lang.String is not possible, and wrapping
String in a new class JSString duplicates
a lot of code since all the built-in string functions need to be
delegated into and out of String. Also the syntax only
slightly changes from str.substring(start, length) to
substring(str, start, length).
Legal Notices, Licensing, Permissions, Privacy Policy.
Advertise | Newsletters | Shopping | E-mail Offers | Freelance Jobs 
Produced by Michael Claßen
All Rights Reserved. Legal Notices.
URL: http://www.webreference.com/xml/column26/3.html
Created: Dec 15, 2000
Revised: Dec 15, 2000
