FileDocCategorySizeDatePackage
GetElementsByTagName.javaAPI DocApache Xerces 3.0.120931Fri Sep 14 20:33:56 BST 2007dom

GetElementsByTagName

public class GetElementsByTagName extends Object
A sample DOM filter. This sample program illustrates how to use the Document#getElementsByTagName() method to quickly and easily locate elements by name.
author
Jeffrey Rodriguez, IBM
author
Andy Clark, IBM
version
$Id: GetElementsByTagName.java 447683 2006-09-19 02:36:31Z mrglavas $

Fields Summary
protected static final String
NAMESPACES_FEATURE_ID
Namespaces feature id (http://xml.org/sax/features/namespaces).
protected static final String
VALIDATION_FEATURE_ID
Validation feature id (http://xml.org/sax/features/validation).
protected static final String
SCHEMA_VALIDATION_FEATURE_ID
Schema validation feature id (http://apache.org/xml/features/validation/schema).
protected static final String
SCHEMA_FULL_CHECKING_FEATURE_ID
Schema full checking feature id (http://apache.org/xml/features/validation/schema-full-checking).
protected static final String
HONOUR_ALL_SCHEMA_LOCATIONS_ID
Honour all schema locations feature id (http://apache.org/xml/features/honour-all-schemaLocations).
protected static final String
VALIDATE_ANNOTATIONS_ID
Validate schema annotations feature id (http://apache.org/xml/features/validate-annotations).
protected static final String
DYNAMIC_VALIDATION_FEATURE_ID
Dynamic validation feature id (http://apache.org/xml/features/validation/dynamic).
protected static final String
XINCLUDE_FEATURE_ID
XInclude feature id (http://apache.org/xml/features/xinclude).
protected static final String
XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID
XInclude fixup base URIs feature id (http://apache.org/xml/features/xinclude/fixup-base-uris).
protected static final String
XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID
XInclude fixup language feature id (http://apache.org/xml/features/xinclude/fixup-language).
protected static final String
DEFAULT_PARSER_NAME
Default parser name (dom.wrappers.Xerces).
protected static final String
DEFAULT_ELEMENT_NAME
Default element name (*).
protected static final boolean
DEFAULT_NAMESPACES
Default namespaces support (true).
protected static final boolean
DEFAULT_VALIDATION
Default validation support (false).
protected static final boolean
DEFAULT_SCHEMA_VALIDATION
Default Schema validation support (false).
protected static final boolean
DEFAULT_SCHEMA_FULL_CHECKING
Default Schema full checking support (false).
protected static final boolean
DEFAULT_HONOUR_ALL_SCHEMA_LOCATIONS
Default honour all schema locations (false).
protected static final boolean
DEFAULT_VALIDATE_ANNOTATIONS
Default validate schema annotations (false).
protected static final boolean
DEFAULT_DYNAMIC_VALIDATION
Default dynamic validation support (false).
protected static final boolean
DEFAULT_XINCLUDE
Default XInclude processing support (false).
protected static final boolean
DEFAULT_XINCLUDE_FIXUP_BASE_URIS
Default XInclude fixup base URIs support (true).
protected static final boolean
DEFAULT_XINCLUDE_FIXUP_LANGUAGE
Default XInclude fixup language support (true).
Constructors Summary
Methods Summary
public static voidmain(java.lang.String[] argv)
Main program entry point.


        // is there anything to do?
        if (argv.length == 0) {
            printUsage();
            System.exit(1);
        }

        // variables
        PrintWriter out = new PrintWriter(System.out);
        ParserWrapper parser = null;
        String elementName = DEFAULT_ELEMENT_NAME;
        String attributeName = null;
        boolean namespaces = DEFAULT_NAMESPACES;
        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;

        // 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.");
                    }
                    String parserName = argv[i];

                    // create parser
                    try {
                        parser = (ParserWrapper)Class.forName(parserName).newInstance();
                    }
                    catch (Exception e) {
                        parser = null;
                        System.err.println("error: Unable to instantiate parser ("+parserName+")");
                    }
                    continue;
                }
                if (option.equals("e")) {
                    if (++i == argv.length) {
                        System.err.println("error: Missing argument to -e option.");
                    }
                    elementName = argv[i];
                    continue;
                }
                if (option.equals("a")) {
                    if (++i == argv.length) {
                        System.err.println("error: Missing argument to -a option.");
                    }
                    attributeName = argv[i];
                    continue;
                }
                if (option.equalsIgnoreCase("n")) {
                    namespaces = option.equals("n");
                    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.equals("h")) {
                    printUsage();
                    continue;
                }
            }

            // use default parser?
            if (parser == null) {

                // create parser
                try {
                    parser = (ParserWrapper)Class.forName(DEFAULT_PARSER_NAME).newInstance();
                }
                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(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 (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+SCHEMA_VALIDATION_FEATURE_ID+")");
            }
            try {
                parser.setFeature(SCHEMA_FULL_CHECKING_FEATURE_ID, schemaFullChecking);
            }
            catch (SAXException 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 (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+HONOUR_ALL_SCHEMA_LOCATIONS_ID+")");
            }
            try {
                parser.setFeature(VALIDATE_ANNOTATIONS_ID, validateAnnotations);
            }
            catch (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+VALIDATE_ANNOTATIONS_ID+")");
            }
            try {
                parser.setFeature(DYNAMIC_VALIDATION_FEATURE_ID, dynamicValidation);
            }
            catch (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+DYNAMIC_VALIDATION_FEATURE_ID+")");
            }
            try {
                parser.setFeature(XINCLUDE_FEATURE_ID, xincludeProcessing);
            }
            catch (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+XINCLUDE_FEATURE_ID+")");
            }
            try {
                parser.setFeature(XINCLUDE_FIXUP_BASE_URIS_FEATURE_ID, xincludeFixupBaseURIs);
            }
            catch (SAXException 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 (SAXException e) {
                System.err.println("warning: Parser does not support feature ("+XINCLUDE_FIXUP_LANGUAGE_FEATURE_ID+")");
            }

            // parse file
            try {
                Document document = parser.parse(arg);
                GetElementsByTagName.print(out, document, elementName, attributeName);
            }
            catch (SAXParseException e) {
                // ignore
            }
            catch (Exception e) {
                System.err.println("error: Parse error occurred - "+e.getMessage());
                if (e instanceof SAXException) {
                    Exception nested = ((SAXException)e).getException();
                    if (nested != null) {
                        e = nested;
                    }
                }
                e.printStackTrace(System.err);
            }
        }
protected static java.lang.Stringnormalize(java.lang.String s)
Normalizes the given string.

        StringBuffer str = new StringBuffer();

        int len = (s != null) ? s.length() : 0;
        for (int i = 0; i < len; i++) {
            char ch = s.charAt(i);
            switch (ch) {
            case '<": {
                    str.append("<");
                    break;
                }
            case '>": {
                    str.append(">");
                    break;
                }
            case '&": {
                    str.append("&");
                    break;
                }
            case '"": {
                    str.append(""");
                    break;
                }
            case '\r":
            case '\n": {
                    str.append("&#");
                    str.append(Integer.toString(ch));
                    str.append(';");
                    break;
                }
            default: {
                    str.append(ch);
                }
            }
        }

        return str.toString();
public static voidprint(java.io.PrintWriter out, org.w3c.dom.Document document, java.lang.String elementName, java.lang.String attributeName)
Prints the specified elements in the given document.


    //
    // Public static methods
    //

             
          
                                 

        // get elements that match
        NodeList elements = document.getElementsByTagName(elementName);

        // is there anything to do?
        if (elements == null) {
            return;
        }

        // print all elements
        if (attributeName == null) {
            int elementCount = elements.getLength();
            for (int i = 0; i < elementCount; i++) {
                Element element = (Element)elements.item(i);
                print(out, element, element.getAttributes());
            }
        }

        // print elements with given attribute name
        else {
            int elementCount = elements.getLength();
            for (int i = 0; i < elementCount; i++) {
                Element      element    = (Element)elements.item(i);
                NamedNodeMap attributes = element.getAttributes();
                if (attributes.getNamedItem(attributeName) != null) {
                    print(out, element, attributes);
                }
            }
        }
protected static voidprint(java.io.PrintWriter out, org.w3c.dom.Element element, org.w3c.dom.NamedNodeMap attributes)
Prints the specified element.


        out.print('<");
        out.print(element.getNodeName());
        if (attributes != null) {
            int attributeCount = attributes.getLength();
            for (int i = 0; i < attributeCount; i++) {
                Attr attribute = (Attr)attributes.item(i);
                out.print(' ");
                out.print(attribute.getNodeName());
                out.print("=\"");
                out.print(normalize(attribute.getNodeValue()));
                out.print('"");
            }
        }
        out.println('>");
        out.flush();
private static voidprintUsage()
Prints the usage.


        System.err.println("usage: java dom.GetElementsByTagName (options) uri ...");
        System.err.println();

        System.err.println("options:");
        System.err.println("  -p name     Select parser by name.");
        System.err.println("  -e name     Specify element name for search.");
        System.err.println("  -a name     Specify attribute name for specified elements.");
        System.err.println("  -n | -N     Turn on/off namespace processing.");
        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("  -h          This help screen.");
        System.err.println();

        System.err.println("defaults:");
        System.err.println("  Parser:     "+DEFAULT_PARSER_NAME);
        System.err.println("  Element:    "+DEFAULT_ELEMENT_NAME);
        System.err.print("  Namespaces: ");
        System.err.println(DEFAULT_NAMESPACES ? "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");