Mega Code Archive
Register a SAX2 ContentHandler and receive callbacks to print information about the document
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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.PrintWriter;
import org.xml.sax.Attributes;
import org.xml.sax.Parser;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.SAXParseException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xml.sax.helpers.ParserAdapter;
import org.xml.sax.helpers.ParserFactory;
import org.xml.sax.helpers.XMLReaderFactory;
/**
* A sample SAX2 counter. This sample program illustrates how to register a SAX2
* ContentHandler and receive the callbacks in order to print information about
* the document. The output of this program shows the time and count of
* elements, attributes, ignorable whitespaces, and characters appearing in the
* document.
* <p>
* This class is useful as a "poor-man's" performance tester to compare the
* speed and accuracy of various SAX parsers. However, it is important to note
* that the first parse time of a parser will include both VM class load time
* and parser initialization that would not be present in subsequent parses with
* the same file.
* <p>
* <strong>Note:</strong> The results produced by this program should never be
* accepted as true performance measurements.
*
* @author Andy Clark, IBM
*
* @version $Id: Counter.java 447686 2006-09-19 02:38:34Z mrglavas $
*/
public class Counter extends DefaultHandler {
//
// Constants
//
// feature ids
/** Namespaces feature id (http://xml.org/sax/features/namespaces). */
protected static final String NAMESPACES_FEATURE_ID = "http://xml.org/sax/features/namespaces";
/**
* Namespace prefixes feature id
* (http://xml.org/sax/features/namespace-prefixes).
*/
protected static final String NAMESPACE_PREFIXES_FEATURE_ID = "http://xml.org/sax/features/namespace-prefixes";
/** Validation feature id (http://xml.org/sax/features/validation). */
protected static final String VALIDATION_FEATURE_ID = "http://xml.org/sax/features/validation";
/**
* Schema validation feature id
* (http://apache.org/xml/features/validation/schema).
*/
protected static final String SCHEMA_VALIDATION_FEATURE_ID = "http://apache.org/xml/features/validation/schema";
/**
* Schema full checking feature id
* (http://apache.org/xml/features/validation/schema-full-checking).
*/
protected static final String SCHEMA_FULL_CHECKING_FEATURE_ID = "http://apache.org/xml/features/validation/schema-full-checking";
/**
* Honour all schema locations feature id
* (http://apache.org/xml/features/honour-all-schemaLocations).
*/
protected static final String HONOUR_ALL_SCHEMA_LOCATIONS_ID = "http://apache.org/xml/features/honour-all-schemaLocations";
/**
* Validate schema annotations feature id
* (http://apache.org/xml/features/validate-annotations)
*/
protected static final String VALIDATE_ANNOTATIONS_ID = "http://apache.org/xml/features/validate-annotations";
/**
* Dynamic validation feature id
* (http://apache.org/xml/features/validation/dynamic).
*/
protected static final String DYNAMIC_VALIDATION_FEATURE_ID = "http://apache.org/xml/features/validation/dynamic";
/** XInclude feature id (http://apache.org/xml/features/xinclude). */
protected static final String XINCLUDE_FEATURE_ID = "http://apache.org/xml/features/xinclude";
/**
* XInclude fixup base URIs feature id
* (http://apache.org/xml/features/xinclude/fixup-base-uris).
*/
protected static final String XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID = "http://apache.org/xml/features/xinclude/fixup-base-uris";
/**
* XInclude fixup language feature id
* (http://apache.org/xml/features/xinclude/fixup-language).
*/
protected static final String XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID = "http://apache.org/xml/features/xinclude/fixup-language";
// default settings
/** Default parser name. */
protected static final String DEFAULT_PARSER_NAME = "org.apache.xerces.parsers.SAXParser";
/** Default repetition (1). */
protected static final int DEFAULT_REPETITION = 1;
/** Default namespaces support (true). */
protected static final boolean DEFAULT_NAMESPACES = true;
/** Default namespace prefixes (false). */
protected static final boolean DEFAULT_NAMESPACE_PREFIXES = false;
/** Default validation support (false). */
protected static final boolean DEFAULT_VALIDATION = false;
/** Default Schema validation support (false). */
protected static final boolean DEFAULT_SCHEMA_VALIDATION = false;
/** Default Schema full checking support (false). */
protected static final boolean DEFAULT_SCHEMA_FULL_CHECKING = false;
/** Default honour all schema locations (false). */
protected static final boolean DEFAULT_HONOUR_ALL_SCHEMA_LOCATIONS = false;
/** Default validate schema annotations (false). */
protected static final boolean DEFAULT_VALIDATE_ANNOTATIONS = false;
/** Default dynamic validation support (false). */
protected static final boolean DEFAULT_DYNAMIC_VALIDATION = false;
/** Default XInclude processing support (false). */
protected static final boolean DEFAULT_XINCLUDE = false;
/** Default XInclude fixup base URIs support (true). */
protected static final boolean DEFAULT_XINCLUDE_FIXUP_BASE_URIS = true;
/** Default XInclude fixup language support (true). */
protected static final boolean DEFAULT_XINCLUDE_FIXUP_LANGUAGE = true;
/** Default memory usage report (false). */
protected static final boolean DEFAULT_MEMORY_USAGE = false;
/** Default "tagginess" report (false). */
protected static final boolean DEFAULT_TAGGINESS = false;
//
// Data
//
/** Number of elements. */
protected long fElements;
/** Number of attributes. */
protected long fAttributes;
/** Number of characters. */
protected long fCharacters;
/** Number of ignorable whitespace characters. */
protected long fIgnorableWhitespace;
/** Number of characters of tags. */
protected long fTagCharacters;
/** Number of other content characters for the "tagginess" calculation. */
protected long fOtherCharacters;
//
// Constructors
//
/** Default constructor. */
public Counter() {
} // <init>()
//
// Public methods
//
/** Prints the results. */
public void printResults(PrintWriter out, String uri, long time, long memory, boolean tagginess,
int repetition) {
// filename.xml: 631 ms (4 elems, 0 attrs, 78 spaces, 0 chars)
out.print(uri);
out.print(": ");
if (repetition == 1) {
out.print(time);
} else {
out.print(time);
out.print('/');
out.print(repetition);
out.print('=');
out.print(time / repetition);
}
out.print(" ms");
if (memory != Long.MIN_VALUE) {
out.print(", ");
out.print(memory);
out.print(" bytes");
}
out.print(" (");
out.print(fElements);
out.print(" elems, ");
out.print(fAttributes);
out.print(" attrs, ");
out.print(fIgnorableWhitespace);
out.print(" spaces, ");
out.print(fCharacters);
out.print(" chars)");
if (tagginess) {
out.print(' ');
long totalCharacters = fTagCharacters + fOtherCharacters + fCharacters + fIgnorableWhitespace;
long tagValue = fTagCharacters * 100 / totalCharacters;
out.print(tagValue);
out.print("% tagginess");
}
out.println();
out.flush();
} // printResults(PrintWriter,String,long)
//
// ContentHandler methods
//
/** Start document. */
public void startDocument() throws SAXException {
fElements = 0;
fAttributes = 0;
fCharacters = 0;
fIgnorableWhitespace = 0;
fTagCharacters = 0;
} // startDocument()
/** Start element. */
public void startElement(String uri, String local, String raw, Attributes attrs)
throws SAXException {
fElements++;
fTagCharacters++; // open angle bracket
fTagCharacters += raw.length();
if (attrs != null) {
int attrCount = attrs.getLength();
fAttributes += attrCount;
for (int i = 0; i < attrCount; i++) {
fTagCharacters++; // space
fTagCharacters += attrs.getQName(i).length();
fTagCharacters++; // '='
fTagCharacters++; // open quote
fOtherCharacters += attrs.getValue(i).length();
fTagCharacters++; // close quote
}
}
fTagCharacters++; // close angle bracket
} // startElement(String,String,StringAttributes)
/** Characters. */
public void characters(char ch[], int start, int length) throws SAXException {
fCharacters += length;
} // characters(char[],int,int);
/** Ignorable whitespace. */
public void ignorableWhitespace(char ch[], int start, int length) throws SAXException {
fIgnorableWhitespace += length;
} // ignorableWhitespace(char[],int,int);
/** Processing instruction. */
public void processingInstruction(String target, String data) throws SAXException {
fTagCharacters += 2; // "<?"
fTagCharacters += target.length();
if (data != null && data.length() > 0) {
fTagCharacters++; // space
fOtherCharacters += data.length();
}
fTagCharacters += 2; // "?>"
} // processingInstruction(String,String)
//
// ErrorHandler methods
//
/** Warning. */
public void warning(SAXParseException ex) throws SAXException {
printError("Warning", ex);
} // warning(SAXParseException)
/** Error. */
public void error(SAXParseException ex) throws SAXException {
printError("Error", ex);
} // error(SAXParseException)
/** Fatal error. */
public void fatalError(SAXParseException ex) throws SAXException {
printError("Fatal Error", ex);
// throw ex;
} // fatalError(SAXParseException)
//
// Protected methods
//
/** Prints the error message. */
protected void printError(String type, SAXParseException ex) {
System.err.print("[");
System.err.print(type);
System.err.print("] ");
if (ex == null) {
System.out.println("!!!");
}
String systemId = ex.getSystemId();
if (systemId != null) {
int index = systemId.lastIndexOf('/');
if (index != -1)
systemId = systemId.substring(index + 1);
System.err.print(systemId);
}
System.err.print(':');
System.err.print(ex.getLineNumber());
System.err.print(':');
System.err.print(ex.getColumnNumber());
System.err.print(": ");
System.err.print(ex.getMessage());
System.err.println();
System.err.flush();
} // printError(String,SAXParseException)
//
// MAIN
//
/** Main program entry point. */
public static void main(String argv[]) {
// is there anything to do?
if (argv.length == 0) {
printUsage();
System.exit(1);
}
// variables
Counter counter = new Counter();
PrintWriter out = new PrintWriter(System.out);
XMLReader parser = null;
int repetition = DEFAULT_REPETITION;
boolean namespaces = DEFAULT_NAMESPACES;
boolean namespacePrefixes = DEFAULT_NAMESPACE_PREFIXES;
boolean validation = DEFAULT_VALIDATION;
boolean schemaValidation = DEFAULT_SCHEMA_VALIDATION;
boolean schemaFullChecking = DEFAULT_SCHEMA_FULL_CHECKING;
boolean honourAllSchemaLocations = DEFAULT_HONOUR_ALL_SCHEMA_LOCATIONS;
boolean validateAnnotations = DEFAULT_VALIDATE_ANNOTATIONS;
boolean dynamicValidation = DEFAULT_DYNAMIC_VALIDATION;
boolean xincludeProcessing = DEFAULT_XINCLUDE;
boolean xincludeFixupBaseURIs = DEFAULT_XINCLUDE_FIXUP_BASE_URIS;
boolean xincludeFixupLanguage = DEFAULT_XINCLUDE_FIXUP_LANGUAGE;
boolean memoryUsage = DEFAULT_MEMORY_USAGE;
boolean tagginess = DEFAULT_TAGGINESS;
// process arguments
for (int i = 0; i < argv.length; i++) {
String arg = argv[i];
if (arg.startsWith("-")) {
String option = arg.substring(1);
if (option.equals("p")) {
// get parser name
if (++i == argv.length) {
System.err.println("error: Missing argument to -p option.");
continue;
}
String parserName = argv[i];
// create parser
try {
parser = XMLReaderFactory.createXMLReader(parserName);
} catch (Exception e) {
try {
Parser sax1Parser = ParserFactory.makeParser(parserName);
parser = new ParserAdapter(sax1Parser);
System.err.println("warning: Features and properties not supported on SAX1 parsers.");
} catch (Exception ex) {
parser = null;
System.err.println("error: Unable to instantiate parser (" + parserName + ")");
}
}
continue;
}
if (option.equals("x")) {
if (++i == argv.length) {
System.err.println("error: Missing argument to -x option.");
continue;
}
String number = argv[i];
try {
int value = Integer.parseInt(number);
if (value < 1) {
System.err.println("error: Repetition must be at least 1.");
continue;
}
repetition = value;
} catch (NumberFormatException e) {
System.err.println("error: invalid number (" + number + ").");
}
continue;
}
if (option.equalsIgnoreCase("n")) {
namespaces = option.equals("n");
continue;
}
if (option.equalsIgnoreCase("np")) {
namespacePrefixes = option.equals("np");
continue;
}
if (option.equalsIgnoreCase("v")) {
validation = option.equals("v");
continue;
}
if (option.equalsIgnoreCase("s")) {
schemaValidation = option.equals("s");
continue;
}
if (option.equalsIgnoreCase("f")) {
schemaFullChecking = option.equals("f");
continue;
}
if (option.equalsIgnoreCase("hs")) {
honourAllSchemaLocations = option.equals("hs");
continue;
}
if (option.equalsIgnoreCase("va")) {
validateAnnotations = option.equals("va");
continue;
}
if (option.equalsIgnoreCase("dv")) {
dynamicValidation = option.equals("dv");
continue;
}
if (option.equalsIgnoreCase("xi")) {
xincludeProcessing = option.equals("xi");
continue;
}
if (option.equalsIgnoreCase("xb")) {
xincludeFixupBaseURIs = option.equals("xb");
continue;
}
if (option.equalsIgnoreCase("xl")) {
xincludeFixupLanguage = option.equals("xl");
continue;
}
if (option.equalsIgnoreCase("m")) {
memoryUsage = option.equals("m");
continue;
}
if (option.equalsIgnoreCase("t")) {
tagginess = option.equals("t");
continue;
}
if (option.equals("-rem")) {
if (++i == argv.length) {
System.err.println("error: Missing argument to -# option.");
continue;
}
System.out.print("# ");
System.out.println(argv[i]);
continue;
}
if (option.equals("h")) {
printUsage();
continue;
}
System.err.println("error: unknown option (" + option + ").");
continue;
}
// use default parser?
if (parser == null) {
// create parser
try {
parser = XMLReaderFactory.createXMLReader(DEFAULT_PARSER_NAME);
} catch (Exception e) {
System.err.println("error: Unable to instantiate parser (" + DEFAULT_PARSER_NAME + ")");
continue;
}
}
// set parser features
try {
parser.setFeature(NAMESPACES_FEATURE_ID, namespaces);
} catch (SAXException e) {
System.err.println("warning: Parser does not support feature (" + NAMESPACES_FEATURE_ID
+ ")");
}
try {
parser.setFeature(NAMESPACE_PREFIXES_FEATURE_ID, namespacePrefixes);
} catch (SAXException e) {
System.err.println("warning: Parser does not support feature ("
+ NAMESPACE_PREFIXES_FEATURE_ID + ")");
}
try {
parser.setFeature(VALIDATION_FEATURE_ID, validation);
} catch (SAXException e) {
System.err.println("warning: Parser does not support feature (" + VALIDATION_FEATURE_ID
+ ")");
}
try {
parser.setFeature(SCHEMA_VALIDATION_FEATURE_ID, schemaValidation);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ SCHEMA_VALIDATION_FEATURE_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ SCHEMA_VALIDATION_FEATURE_ID + ")");
}
try {
parser.setFeature(SCHEMA_FULL_CHECKING_FEATURE_ID, schemaFullChecking);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ SCHEMA_FULL_CHECKING_FEATURE_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ SCHEMA_FULL_CHECKING_FEATURE_ID + ")");
}
try {
parser.setFeature(HONOUR_ALL_SCHEMA_LOCATIONS_ID, honourAllSchemaLocations);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ HONOUR_ALL_SCHEMA_LOCATIONS_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ HONOUR_ALL_SCHEMA_LOCATIONS_ID + ")");
}
try {
parser.setFeature(VALIDATE_ANNOTATIONS_ID, validateAnnotations);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature (" + VALIDATE_ANNOTATIONS_ID
+ ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature (" + VALIDATE_ANNOTATIONS_ID
+ ")");
}
try {
parser.setFeature(DYNAMIC_VALIDATION_FEATURE_ID, dynamicValidation);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ DYNAMIC_VALIDATION_FEATURE_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ DYNAMIC_VALIDATION_FEATURE_ID + ")");
}
try {
parser.setFeature(XINCLUDE_FEATURE_ID, xincludeProcessing);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature (" + XINCLUDE_FEATURE_ID
+ ")");
} catch (SAXNotSupportedException e) {
System.err
.println("warning: Parser does not support feature (" + XINCLUDE_FEATURE_ID + ")");
}
try {
parser.setFeature(XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID, xincludeFixupBaseURIs);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID + ")");
}
try {
parser.setFeature(XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID, xincludeFixupLanguage);
} catch (SAXNotRecognizedException e) {
System.err.println("warning: Parser does not recognize feature ("
+ XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID + ")");
} catch (SAXNotSupportedException e) {
System.err.println("warning: Parser does not support feature ("
+ XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID + ")");
}
// parse file
parser.setContentHandler(counter);
parser.setErrorHandler(counter);
try {
long timeBefore = System.currentTimeMillis();
long memoryBefore = Runtime.getRuntime().freeMemory();
for (int j = 0; j < repetition; j++) {
parser.parse(arg);
}
long memoryAfter = Runtime.getRuntime().freeMemory();
long timeAfter = System.currentTimeMillis();
long time = timeAfter - timeBefore;
long memory = memoryUsage ? memoryBefore - memoryAfter : Long.MIN_VALUE;
counter.printResults(out, arg, time, memory, tagginess, repetition);
} catch (SAXParseException e) {
// ignore
} catch (Exception e) {
System.err.println("error: Parse error occurred - " + e.getMessage());
Exception se = e;
if (e instanceof SAXException) {
se = ((SAXException) e).getException();
}
if (se != null)
se.printStackTrace(System.err);
else
e.printStackTrace(System.err);
}
}
} // main(String[])
//
// Private static methods
//
/** Prints the usage. */
private static void printUsage() {
System.err.println("usage: java sax.Counter (options) uri ...");
System.err.println();
System.err.println("options:");
System.err.println(" -p name Select parser by name.");
System.err.println(" -x number Select number of repetitions.");
System.err.println(" -n | -N Turn on/off namespace processing.");
System.err.println(" -np | -NP Turn on/off namespace prefixes.");
System.err.println(" NOTE: Requires use of -n.");
System.err.println(" -v | -V Turn on/off validation.");
System.err.println(" -s | -S Turn on/off Schema validation support.");
System.err.println(" NOTE: Not supported by all parsers.");
System.err.println(" -f | -F Turn on/off Schema full checking.");
System.err.println(" NOTE: Requires use of -s and not supported by all parsers.");
System.err.println(" -hs | -HS Turn on/off honouring of all schema locations.");
System.err.println(" NOTE: Requires use of -s and not supported by all parsers.");
System.err.println(" -va | -VA Turn on/off validation of schema annotations.");
System.err.println(" NOTE: Requires use of -s and not supported by all parsers.");
System.err.println(" -dv | -DV Turn on/off dynamic validation.");
System.err.println(" NOTE: Not supported by all parsers.");
System.err.println(" -xi | -XI Turn on/off XInclude processing.");
System.err.println(" NOTE: Not supported by all parsers.");
System.err.println(" -xb | -XB Turn on/off base URI fixup during XInclude processing.");
System.err.println(" NOTE: Requires use of -xi and not supported by all parsers.");
System.err.println(" -xl | -XL Turn on/off language fixup during XInclude processing.");
System.err.println(" NOTE: Requires use of -xi and not supported by all parsers.");
System.err.println(" -m | -M Turn on/off memory usage report");
System.err.println(" -t | -T Turn on/off \"tagginess\" report.");
System.err.println(" --rem text Output user defined comment before next parse.");
System.err.println(" -h This help screen.");
System.err.println();
System.err.println("defaults:");
System.err.println(" Parser: " + DEFAULT_PARSER_NAME);
System.err.println(" Repetition: " + DEFAULT_REPETITION);
System.err.print(" Namespaces: ");
System.err.println(DEFAULT_NAMESPACES ? "on" : "off");
System.err.print(" Prefixes: ");
System.err.println(DEFAULT_NAMESPACE_PREFIXES ? "on" : "off");
System.err.print(" Validation: ");
System.err.println(DEFAULT_VALIDATION ? "on" : "off");
System.err.print(" Schema: ");
System.err.println(DEFAULT_SCHEMA_VALIDATION ? "on" : "off");
System.err.print(" Schema full checking: ");
System.err.println(DEFAULT_SCHEMA_FULL_CHECKING ? "on" : "off");
System.err.print(" Honour all schema locations: ");
System.err.println(DEFAULT_HONOUR_ALL_SCHEMA_LOCATIONS ? "on" : "off");
System.err.print(" Validate annotations: ");
System.err.println(DEFAULT_VALIDATE_ANNOTATIONS ? "on" : "off");
System.err.print(" Dynamic: ");
System.err.println(DEFAULT_DYNAMIC_VALIDATION ? "on" : "off");
System.err.print(" XInclude: ");
System.err.println(DEFAULT_XINCLUDE ? "on" : "off");
System.err.print(" XInclude base URI fixup: ");
System.err.println(DEFAULT_XINCLUDE_FIXUP_BASE_URIS ? "on" : "off");
System.err.print(" XInclude language fixup: ");
System.err.println(DEFAULT_XINCLUDE_FIXUP_LANGUAGE ? "on" : "off");
System.err.print(" Memory: ");
System.err.println(DEFAULT_MEMORY_USAGE ? "on" : "off");
System.err.print(" Tagginess: ");
System.err.println(DEFAULT_TAGGINESS ? "on" : "off");
System.err.println();
System.err.println("notes:");
System.err
.println(" The speed and memory results from this program should NOT be used as the");
System.err
.println(" basis of parser performance comparison! Real analytical methods should be");
System.err
.println(" used. For better results, perform multiple document parses within the same");
System.err
.println(" virtual machine to remove class loading from parse time and memory usage.");
System.err.println();
System.err
.println(" The \"tagginess\" measurement gives a rough estimate of the percentage of");
System.err.println(" markup versus content in the XML document. The percent tagginess of a ");
System.err.println(" document is equal to the minimum amount of tag characters required for ");
System.err.println(" elements, attributes, and processing instructions divided by the total");
System.err
.println(" amount of characters (characters, ignorable whitespace, and tag characters)");
System.err.println(" in the document.");
System.err.println();
System.err.println(" Not all features are supported by different parsers.");
} // printUsage()
} // class Counter
]]>