Changeset 1884

Timestamp:

2001-01-31T14:14:41+13:00 (23 years ago)

Author:

paynter

Message:

Added some documentation.

File:

• trunk/gsdl/perllib/classify/BasClas.pm (modified) (2 diffs)

trunk/gsdl/perllib/classify/BasClas.pm

@@ -2 +2 @@
 #
 # BasClas.pm -- base class for all classifiers
+#
 # A component of the Greenstone digital library software
 # from the New Zealand Digital Library Project at the 
@@ -26 +27 @@
 package BasClas;
 
+# How a classifier works.  
+#
+# For each classifier requested in the collect.cfg file, buildcol.pl creates
+# a new classifier object (a subclass of BasClas).  Later, it passes each 
+# document object to each classifier in turn for classification.
+#
+# Four primary functions are used:
+#
+# 1. "new" is called before the documents are processed to set up the
+#    classifier.
+#
+# 2. "init" is called after buildcol.pl has created the indexes etc but
+#    before the documents are classified in order that the classifier might
+#    set any variables it requires, etc.
+#
+# 3. "classify" is called once for each document object.  The classifier
+#    "classifies" each document and updates its local data accordingly.
+#
+# 4. "get_classify_info" is called after every document has been
+#    classified.  It collates the information about the documents and
+#    stores a reference to the classifier so that Greenstone can later
+#    display it.
+
 use parsargv;
-
 
 sub print_general_usage {
     my ($plugin_name) = @_;
-    print STDERR "\n  usage: plugin $plugin_name [options]\n\n";
+    print STDERR "
+  usage: plugin $plugin_name [options]
+
+";
 }
 
 # print_usage should be overridden for any sub-classes
 sub print_usage {
-    print STDERR "\nThis classifier has no classifier-specific options\n\n";
+    print STDERR "
+This classifier has no classifier-specific options
 
+";
 }