Counter program for validation of XML, from Apache
--extended to take a schema spec as argument: -s -v -schema foo.xsd

Referenced in Harold, XML Bible 1.1, Chap. 20
(From the samples directory of the Xerces parser distribution
available at xml.apache.org.)

I've edited this version of Counter.java to use the default SAX parser
in J2SE, so we don't need any special classpath to run it.  

Counter.java is in the sax subdirectory of this directory, as
is normal because it is in package "sax".  To run it, be connected
to this directory and do the commands like the examples below.

Note the extra output over what is reported in Harold.  These are
just nitpicking warnings about missing features of the parser,
which we don't need to worry about.  NEW: These are now removed.

This is an example of a tool built using the functionality of the
now-standard Java libraries for XML. 

Examples of use, from Harold's XML Bible, redone with this program:
Flags in use:
none:  just check well-formedness
-v:    do validation using DTD if there
-v -s: do schema validation
-v -s -schema foo.xsd   use this schema: NEW FEATURE 

java sax.Counter -v -s valid_greeting.xml
outputs:
valid_greeting.xml: 344 ms (1 elems, 1 attrs, 0 spaces, 12 chars)

java sax.Counter -v -s invalid_greeting.xml
[Error] invalid_greeting.xml:6:12: cvc-type.3.1.2: Element 'GREETING' is a simple type, so it must have no element information item [children].
invalid_greeting.xml: 516 ms (2 elems, 1 attrs, 0 spaces, 14 chars)


Recursive XML example
book.dtd: DTD
book.xsd: no-namespace schema
book1.xsd: schema with target NS = "book"   NEW
  Note use of elementFormDefault="qualified" in book1.xsd

book.xml: plain XML
book1.xml: no NS, linkage in doc to DTD book.dtd
book2.xml: no NS, linkage in doc to book.xsd
book3.xml: default NS, no schema linkage (but valid by book1.xsd)  NEW
book4.xml: prefix b: for NS, no schema linkage (but valid by book1.xsd) NEW
book5.xml: default NS, linkage in doc to book1.xsd NEW
book6.xml: prefix b: for NS, schema linkage in doc to book1.xsd NEW

Example: use book1.xsd to validate book3.xml
java sax/Counter -v -s -schema book1.xsd book3.xml

For other examples with book*, see targets in build.xml

booktype.xmd: defines BookType, the type of a book in book.xml
books.xsd: uses BookType from booktype by import, to set up bookgroup type
books.xml: a bookgroup document

booksmsg.xml: SOAP message with books xml as body
soapbooksmsg.xmd: a schema to validate booksmsg.xml

Other older examples:
order.dtd: DTD for Order from text
order.xsd: schema for Order from text
clocks.xml: plain XML
clocks1.xml: same XML with DOCTYPE for DTD
clocks2.xml: same XML with schema

java sax.Counter -v clocks1.xml             does DTD validation