view netx/net/sourceforge/jnlp/Parser.java @ 776:94ff58f33514

Backported warnings cleanups from head itw itself warning cleanup: fixed rawtypes and unchecks, added braces and Override unittests warning cleanup: fixed typechecks, rawtypes, redundant casts... ScreenFinder fixed to work partially also in headless mode kept comaptible with jdk6 After this clean up only "internal proprietary API and may be removed in a future release" warnings remain fro make check. Please keep itw in this way :)
author Jiri Vanek <jvanek@redhat.com>
date Fri, 13 Dec 2013 13:28:55 +0100
parents c3d0eaf5460c
children
line wrap: on
line source

// Copyright (C) 2001-2003 Jon A. Maxwell (JAM)
// Copyright (C) 2012 Red Hat, Inc.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

package net.sourceforge.jnlp;

import static net.sourceforge.jnlp.runtime.Translator.R;

import java.io.*;
import java.net.*;
import java.util.*;
//import javax.xml.parsers.*; // commented to use right Node
//import org.w3c.dom.*;       // class for using Tiny XML | NanoXML
//import org.xml.sax.*;
//import gd.xml.tiny.*;
import net.sourceforge.jnlp.UpdateDesc.Check;
import net.sourceforge.jnlp.UpdateDesc.Policy;
import net.sourceforge.jnlp.runtime.JNLPRuntime;
import net.sourceforge.nanoxml.*;

/**
 * Contains methods to parse an XML document into a JNLPFile.
 * Implements JNLP specification version 1.0.
 *
 * @author <a href="mailto:jmaxwell@users.sourceforge.net">Jon A. Maxwell (JAM)</a> - initial author
 * @version $Revision: 1.13 $
 */
class Parser {

    // defines netx.jnlp.Node class if using Tiny XML or Nano XML

    // Currently uses the Nano XML parse.  Search for "SAX" or
    // "TINY" or "NANO" and uncomment those blocks and comment the
    // active ones (if any) to switch XML parsers.  Also
    // (un)comment appropriate Node class at end of this file and
    // do a clean build.

    /**
     * Ensure consistent error handling.
     */
    /* SAX
    static ErrorHandler errorHandler = new ErrorHandler() {
        public void error(SAXParseException exception) throws SAXParseException {
            //throw exception;
        }
        public void fatalError(SAXParseException exception) throws SAXParseException {
            //throw exception;
        }
        public void warning(SAXParseException exception) {
            System.err.println("XML parse warning:");
            exception.printStackTrace();
        }
    };
    */

    // fix: some descriptors need to use the jnlp file at a later
    // date and having file ref lets us pass it to their
    // constructors
    //
    /** the file reference */
    private JNLPFile file; // do not use (uninitialized)

    /** the root node */
    private Node root;

    /** the specification version */
    private Version spec;

    /** the base URL that all hrefs are relative to */
    private URL base;

    /** the codebase URL */
    private URL codebase;

    /** the file URL */
    private URL fileLocation;

    /** whether to throw errors on non-fatal errors. */
    private boolean strict; // if strict==true parses a file with no error then strict==false should also

    /** whether to allow extensions to the JNLP specification */
    private boolean allowExtensions; // true if extensions to JNLP spec are ok

    /**
     * Create a parser for the JNLP file.  If the location
     * parameters is not null it is used as the default codebase
     * (does not override value of jnlp element's href
     * attribute).<p>
     *
     * The root node may be normalized as a side effect of this
     * constructor.
     *
     * @param file the (uninitialized) file reference
     * @param base if codebase is not specified, a default base for relative URLs
     * @param root the root node
     * @param strict whether to enforce strict compliance with the JNLP spec
     * @param allowExtensions whether to allow extensions to the JNLP spec
     * @throws ParseException if the JNLP file is invalid
     */
    public Parser(JNLPFile file, URL base, Node root, boolean strict, boolean allowExtensions) throws ParseException {
	this(file, base, root, strict, allowExtensions, null);
    }

    /**
     * Create a parser for the JNLP file.  If the location
     * parameters is not null it is used as the default codebase
     * (does not override value of jnlp element's href
     * attribute).<p>
     *
     * The root node may be normalized as a side effect of this
     * constructor.
     *
     * @param file the (uninitialized) file reference
     * @param base if codebase is not specified, a default base for relative URLs
     * @param root the root node
     * @param strict whether to enforce strict compliance with the JNLP spec
     * @param allowExtensions whether to allow extensions to the JNLP spec
     * @param codebase codebase to use if we did not parse one from JNLP file.
     * @throws ParseException if the JNLP file is invalid
     */
    public Parser(JNLPFile file, URL base, Node root, boolean strict, boolean allowExtensions, URL codebase) throws ParseException {
        this.file = file;
        this.root = root;
        this.strict = strict;
        this.allowExtensions = allowExtensions;

        // ensure it's a JNLP node
        if (root == null || !root.getNodeName().equals("jnlp"))
            throw new ParseException(R("PInvalidRoot"));

        // JNLP tag information
        this.spec = getVersion(root, "spec", "1.0+");

        try {
            this.codebase = addSlash(getURL(root, "codebase", base));
        } catch (ParseException e) {
            //If parsing fails, continue by overriding the codebase with the one passed in
        }

        if (this.codebase == null) // Codebase is overwritten if codebase was not specified in file or if parsing of it failed
            this.codebase = codebase;

        this.base = (this.codebase != null) ? this.codebase : base; // if codebase not specified use default codebase
        fileLocation = getURL(root, "href", this.base);

        // normalize the text nodes
        root.normalize();
    }

    /**
     * Returns the file version.
     */
    public Version getFileVersion() {
        return getVersion(root, "version", null);
    }

    /**
     * Returns the file location.
     */
    public URL getFileLocation() {
        return fileLocation;
    }

    /**
     * Returns the codebase.
     */
    public URL getCodeBase() {
        return codebase;
    }

    /**
     * Returns the specification version.
     */
    public Version getSpecVersion() {
        return spec;
    }

    public UpdateDesc getUpdate(Node parent) throws ParseException {
        UpdateDesc updateDesc = null;
        Node child = parent.getFirstChild();
        while (child != null) {
            if (child.getNodeName().equals("update")) {
                if (strict && updateDesc != null) {
                    throw new ParseException(R("PTwoUpdates"));
                }

                Node node = child;

                Check check;
                String checkValue = getAttribute(node, "check", "timeout");
                if (checkValue.equals("always")) {
                    check = Check.ALWAYS;
                } else if (checkValue.equals("timeout")) {
                    check = Check.TIMEOUT;
                } else if (checkValue.equals("background")) {
                    check = Check.BACKGROUND;
                } else {
                    check = Check.TIMEOUT;
                }

                String policyString = getAttribute(node, "policy", "always");
                Policy policy;
                if (policyString.equals("always")) {
                    policy = Policy.ALWAYS;
                } else if (policyString.equals("prompt-update")) {
                    policy = Policy.PROMPT_UPDATE;
                } else if (policyString.equals("prompt-run")) {
                    policy = Policy.PROMPT_RUN;
                } else {
                    policy = Policy.ALWAYS;
                }

                updateDesc = new UpdateDesc(check, policy);
            }

            child = child.getNextSibling();
        }

        if (updateDesc == null) {
            updateDesc = new UpdateDesc(Check.TIMEOUT, Policy.ALWAYS);
        }
        return updateDesc;
    }

    //
    // This section loads the resources elements
    //

    /**
     * Returns all of the ResourcesDesc elements under the specified
     * node (jnlp or j2se).
     *
     * @param parent the parent node (either jnlp or j2se)
     * @param j2se true if the resources are located under a j2se or java node
     * @throws ParseException if the JNLP file is invalid
     */
    public List<ResourcesDesc> getResources(Node parent, boolean j2se)
            throws ParseException {
        List<ResourcesDesc> result = new ArrayList<ResourcesDesc>();
        Node resources[] = getChildNodes(parent, "resources");

        // ensure that there are at least one information section present
        if (resources.length == 0 && !j2se)
            throw new ParseException(R("PNoResources"));

        // create objects from the resources sections
        for (int i = 0; i < resources.length; i++)
            result.add(getResourcesDesc(resources[i], j2se));

        return result;
    }

    /**
     * Returns the ResourcesDesc element at the specified node.
     *
     * @param node the resources node
     * @param j2se true if the resources are located under a j2se or java node
     * @throws ParseException if the JNLP file is invalid
     */
    public ResourcesDesc getResourcesDesc(Node node, boolean j2se) throws ParseException {
        boolean mainFlag = false; // if found a main tag

        // create resources
        ResourcesDesc resources =
                new ResourcesDesc(file,
                              getLocales(node),
                              splitString(getAttribute(node, "os", null)),
                              splitString(getAttribute(node, "arch", null)));

        // step through the elements
        Node child = node.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            // check for nativelib but no trusted environment
            if ("nativelib".equals(name))
                if (!isTrustedEnvironment())
                    throw new ParseException(R("PUntrustedNative"));

            if ("j2se".equals(name) || "java".equals(name)) {
                if (getChildNode(root, "component-desc") != null)
                    if (strict)
                        throw new ParseException(R("PExtensionHasJ2SE"));
                if (!j2se)
                    resources.addResource(getJRE(child));
                else
                    throw new ParseException(R("PInnerJ2SE"));
            }

            if ("jar".equals(name) || "nativelib".equals(name)) {
                JARDesc jar = getJAR(child);

                // check for duplicate main entries
                if (jar.isMain()) {
                    if (mainFlag == true)
                        if (strict)
                            throw new ParseException(R("PTwoMains"));
                    mainFlag = true;
                }

                resources.addResource(jar);
            }

            if ("extension".equals(name))
                resources.addResource(getExtension(child));

            if ("property".equals(name))
                resources.addResource(getProperty(child));

            if ("package".equals(name))
                resources.addResource(getPackage(child));

            child = child.getNextSibling();
        }

        return resources;
    }

    /**
     * Returns the JRE element at the specified node.
     *
     * @param node the j2se/java node
     * @throws ParseException if the JNLP file is invalid
     */
    public JREDesc getJRE(Node node) throws ParseException {
        Version version = getVersion(node, "version", null);
        URL location = getURL(node, "href", base);
        String vmArgs = getAttribute(node, "java-vm-args", null);
        try {
            checkVMArgs(vmArgs);
        } catch (IllegalArgumentException argumentException) {
            vmArgs = null;
        }
        String initialHeap = getAttribute(node, "initial-heap-size", null);
        String maxHeap = getAttribute(node, "max-heap-size", null);
        List<ResourcesDesc> resources = getResources(node, true);

        // require version attribute
        getRequiredAttribute(node, "version", null);

        return new JREDesc(version, location, vmArgs, initialHeap, maxHeap, resources);
    }

    /**
     * Returns the JAR element at the specified node.
     *
     * @param node the jar or nativelib node
     * @throws ParseException if the JNLP file is invalid
     */
    public JARDesc getJAR(Node node) throws ParseException {
        boolean nativeJar = "nativelib".equals(node.getNodeName());
        URL location = getRequiredURL(node, "href", base);
        Version version = getVersion(node, "version", null);
        String part = getAttribute(node, "part", null);
        boolean main = "true".equals(getAttribute(node, "main", "false"));
        boolean lazy = "lazy".equals(getAttribute(node, "download", "eager"));

        if (nativeJar && main)
            if (strict)
                throw new ParseException(R("PNativeHasMain"));

        return new JARDesc(location, version, part, lazy, main, nativeJar, true);

    }

    /**
     * Returns the Extension element at the specified node.
     *
     * @param node the extension node
     * @throws ParseException if the JNLP file is invalid
     */
    public ExtensionDesc getExtension(Node node) throws ParseException {
        String name = getAttribute(node, "name", null);
        Version version = getVersion(node, "version", null);
        URL location = getRequiredURL(node, "href", base);

        ExtensionDesc ext = new ExtensionDesc(name, version, location);

        Node dload[] = getChildNodes(node, "ext-download");
        for (int i = 0; i < dload.length; i++) {
            boolean lazy = "lazy".equals(getAttribute(dload[i], "download", "eager"));

            ext.addPart(getRequiredAttribute(dload[i], "ext-part", null),
                        getAttribute(dload[i], "part", null),
                        lazy);
        }

        return ext;
    }

    /**
     * Returns the Property element at the specified node.
     *
     * @param node the property node
     * @throws ParseException if the JNLP file is invalid
     */
    public PropertyDesc getProperty(Node node) throws ParseException {
        String name = getRequiredAttribute(node, "name", null);
        String value = getRequiredAttribute(node, "value", "");

        return new PropertyDesc(name, value);
    }

    /**
     * Returns the Package element at the specified node.
     *
     * @param node the package node
     * @throws ParseException if the JNLP file is invalid
     */
    public PackageDesc getPackage(Node node) throws ParseException {
        String name = getRequiredAttribute(node, "name", null);
        String part = getRequiredAttribute(node, "part", "");
        boolean recursive = getAttribute(node, "recursive", "false").equals("true");

        return new PackageDesc(name, part, recursive);
    }

    //
    // This section loads the information elements
    //

    /**
     * Make sure a title and vendor are present and nonempty and localized as
     * best matching as possible for the JVM's current locale. Fallback to a
     * generalized title and vendor otherwise. If none is found, throw an exception.
     *
     * Additionally prints homepage, description, title and vendor to stdout
     * if in Debug mode.
     * @throws RequiredElementException
     */
    void checkForInformation() throws RequiredElementException {
        if (JNLPRuntime.isDebug()) {
            System.out.println("Homepage: " + file.getInformation().getHomepage());
            System.out.println("Description: " + file.getInformation().getDescription());
        }

        String title = file.getTitle();
        String vendor = file.getVendor();

        if (title == null || title.trim().isEmpty())
            throw new MissingTitleException();
        else if (JNLPRuntime.isDebug())
            System.out.println("Acceptable title tag found, contains: " + title);

        if (vendor == null || vendor.trim().isEmpty())
            throw new MissingVendorException();
        else if (JNLPRuntime.isDebug())
            System.out.println("Acceptable vendor tag found, contains: " + vendor);
    }

    /**
     * Returns all of the information elements under the specified
     * node.
     *
     * @param parent the parent node (jnlp)
     * @throws ParseException if the JNLP file is invalid
     */
    public List<InformationDesc> getInfo(Node parent)
            throws ParseException {
        List<InformationDesc> result = new ArrayList<InformationDesc>();
        Node info[] = getChildNodes(parent, "information");

        // ensure that there are at least one information section present
        if (info.length == 0)
            throw new MissingInformationException();

        // create objects from the info sections
        for (Node infoNode : info) {
            result.add(getInformationDesc(infoNode));
        }

        return result;
    }

    /**
     * Returns the information element at the specified node.
     *
     * @param node the information node
     * @throws ParseException if the JNLP file is invalid
     */
    public InformationDesc getInformationDesc(Node node) throws ParseException {
        List<String> descriptionsUsed = new ArrayList<String>();

        // locale
        Locale locales[] = getLocales(node);

        // create information
        InformationDesc info = new InformationDesc(file, locales);

        // step through the elements
        Node child = node.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            if ("title".equals(name))
                addInfo(info, child, null, getSpanText(child, false));
            if ("vendor".equals(name))
                addInfo(info, child, null, getSpanText(child, false));
            if ("description".equals(name)) {
                String kind = getAttribute(child, "kind", "default");
                if (descriptionsUsed.contains(kind))
                    if (strict)
                        throw new ParseException(R("PTwoDescriptions", kind));

                descriptionsUsed.add(kind);
                addInfo(info, child, kind, getSpanText(child, false));
            }
            if ("homepage".equals(name))
                addInfo(info, child, null, getRequiredURL(child, "href", base));
            if ("icon".equals(name))
                addInfo(info, child, getAttribute(child, "kind", "default"), getIcon(child));
            if ("offline-allowed".equals(name))
                addInfo(info, child, null, Boolean.TRUE);
            if ("sharing-allowed".equals(name)) {
                if (strict && !allowExtensions)
                    throw new ParseException(R("PSharing"));
                addInfo(info, child, null, Boolean.TRUE);
            }
            if ("association".equals(name)) {
                addInfo(info, child, null, getAssociation(child));
            }
            if ("shortcut".equals(name)) {
                addInfo(info, child, null, getShortcut(child));
            }
            if ("related-content".equals(name)) {
                addInfo(info, child, null, getRelatedContent(child));
            }

            child = child.getNextSibling();
        }

        return info;
    }

    /**
     * Adds a key,value pair to the information object.
     *
     * @param info the information object
     * @param node node name to be used as the key
     * @param mod key name appended with "-"+mod if not null
     * @param value the info object to add (icon or string)
     */
    protected void addInfo(InformationDesc info, Node node, String mod, Object value) {
        String modStr = (mod == null) ? "" : "-" + mod;

        if (node == null)
            return;

        info.addItem(node.getNodeName() + modStr, value);
    }

    /**
     * Returns the icon element at the specified node.
     *
     * @param node the icon node
     * @throws ParseException if the JNLP file is invalid
     */
    public IconDesc getIcon(Node node) throws ParseException {
        int width = Integer.parseInt(getAttribute(node, "width", "-1"));
        int height = Integer.parseInt(getAttribute(node, "height", "-1"));
        int size = Integer.parseInt(getAttribute(node, "size", "-1"));
        int depth = Integer.parseInt(getAttribute(node, "depth", "-1"));
        URL location = getRequiredURL(node, "href", base);
        Object kind = getAttribute(node, "kind", "default");

        return new IconDesc(location, kind, width, height, depth, size);
    }

    //
    // This section loads the security descriptor element
    //

    /**
     * Returns the security descriptor element.  If no security
     * element was specified in the JNLP file then a SecurityDesc
     * with applet permissions is returned.
     *
     * @param parent the parent node
     * @throws ParseException if the JNLP file is invalid
     */
    public SecurityDesc getSecurity(Node parent) throws ParseException {
        Node nodes[] = getChildNodes(parent, "security");

        // test for too many security elements
        if (nodes.length > 1)
            if (strict)
                throw new ParseException(R("PTwoSecurity"));

        Object type = SecurityDesc.SANDBOX_PERMISSIONS;

        if (nodes.length == 0)
            type = SecurityDesc.SANDBOX_PERMISSIONS;
        else if (null != getChildNode(nodes[0], "all-permissions"))
            type = SecurityDesc.ALL_PERMISSIONS;
        else if (null != getChildNode(nodes[0], "j2ee-application-client-permissions"))
            type = SecurityDesc.J2EE_PERMISSIONS;
        else if (strict)
            throw new ParseException(R("PEmptySecurity"));

        if (base != null)
            return new SecurityDesc(file, type, base.getHost());
        else
            return new SecurityDesc(file, type, null);
    }

    /**
     * Returns whether the JNLP file requests a trusted execution
     * environment.
     */
    protected boolean isTrustedEnvironment() {
        Node security = getChildNode(root, "security");

        if (security != null)
            if (getChildNode(security, "all-permissions") != null
                    || getChildNode(security, "j2ee-application-client-permissions") != null)
                return true;

        return false;
    }

    //
    // This section loads the launch descriptor element
    //

    /**
     * Returns the launch descriptor element, either AppletDesc,
     * ApplicationDesc, or InstallerDesc.
     *
     * @param parent the parent node
     * @throws ParseException if the JNLP file is invalid
     */
    public LaunchDesc getLauncher(Node parent) throws ParseException {
        // check for other than one application type
        if (1 < getChildNodes(parent, "applet-desc").length
                + getChildNodes(parent, "application-desc").length
                + getChildNodes(parent, "installer-desc").length)
            throw new ParseException(R("PTwoDescriptors"));

        Node child = parent.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            if ("applet-desc".equals(name))
                return getApplet(child);
            if ("application-desc".equals(name))
                return getApplication(child);
            if ("installer-desc".equals(name))
                return getInstaller(child);

            child = child.getNextSibling();
        }

        // not reached
        return null;
    }

    /**
     * Returns the applet descriptor.
     *
     * @throws ParseException if the JNLP file is invalid
     */
    public AppletDesc getApplet(Node node) throws ParseException {
        String name = getRequiredAttribute(node, "name", R("PUnknownApplet"));
        String main = getRequiredAttribute(node, "main-class", null);
        URL docbase = getURL(node, "documentbase", base);
        Map<String, String> paramMap = new HashMap<String, String>();
        int width = 0;
        int height = 0;

        try {
            width = Integer.parseInt(getRequiredAttribute(node, "width", "100"));
            height = Integer.parseInt(getRequiredAttribute(node, "height", "100"));
        } catch (NumberFormatException nfe) {
            if (width <= 0)
                throw new ParseException(R("PBadWidth"));
            throw new ParseException(R("PBadWidth"));
        }

        // read params
        Node params[] = getChildNodes(node, "param");
        for (int i = 0; i < params.length; i++) {
            paramMap.put(getRequiredAttribute(params[i], "name", null),
                         getRequiredAttribute(params[i], "value", ""));
        }

        return new AppletDesc(name, main, docbase, width, height, paramMap);
    }

    /**
     * Returns the application descriptor.
     *
     * @throws ParseException if the JNLP file is invalid
     */
    public ApplicationDesc getApplication(Node node) throws ParseException {
        String main = getAttribute(node, "main-class", null);
        List<String> argsList = new ArrayList<String>();

        // if (main == null)
        //   only ok if can be found in main jar file (can't check here but make a note)

        // read parameters
        Node args[] = getChildNodes(node, "argument");
        for (int i = 0; i < args.length; i++) {
            //argsList.add( args[i].getNodeValue() );

            //This approach was not finding the argument text
            argsList.add(getSpanText(args[i]));
        }

        String argStrings[] = argsList.toArray(new String[argsList.size()]);

        return new ApplicationDesc(main, argStrings);
    }

    /**
     * Returns the component descriptor.
     */
    public ComponentDesc getComponent(Node parent) throws ParseException {

        if (1 < getChildNodes(parent, "component-desc").length) {
            throw new ParseException(R("PTwoDescriptors"));
        }

        Node child = parent.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            if ("component-desc".equals(name))
                return new ComponentDesc();

            child = child.getNextSibling();
        }

        return null;
    }

    /**
     * Returns the installer descriptor.
     */
    public InstallerDesc getInstaller(Node node) {
        String main = getAttribute(node, "main-class", null);

        return new InstallerDesc(main);
    }

    /**
     * Returns the association descriptor.
     */
    public AssociationDesc getAssociation(Node node) throws ParseException {
        String[] extensions = getRequiredAttribute(node, "extensions", null).split(" ");
        String mimeType = getRequiredAttribute(node, "mime-type", null);

        return new AssociationDesc(mimeType, extensions);
    }

    /**
     * Returns the shortcut descriptor.
     */
    public ShortcutDesc getShortcut(Node node) throws ParseException {

        String online = getAttribute(node, "online", "true");
        boolean shortcutIsOnline = Boolean.valueOf(online);

        boolean showOnDesktop = false;
        MenuDesc menu = null;

        // step through the elements
        Node child = node.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            if ("desktop".equals(name)) {
                if (showOnDesktop && strict) {
                    throw new ParseException(R("PTwoDesktops"));
                }
                showOnDesktop = true;
            } else if ("menu".equals(name)) {
                if (menu != null && strict) {
                    throw new ParseException(R("PTwoMenus"));
                }
                menu = getMenu(child);
            }

            child = child.getNextSibling();
        }

        ShortcutDesc shortcut = new ShortcutDesc(shortcutIsOnline, showOnDesktop);
        if (menu != null) {
            shortcut.addMenu(menu);
        }
        return shortcut;
    }

    /**
     * Returns the menu descriptor.
     */
    public MenuDesc getMenu(Node node) {
        String subMenu = getAttribute(node, "submenu", null);

        return new MenuDesc(subMenu);
    }

    /**
     * Returns the related-content descriptor.
     */
    public RelatedContentDesc getRelatedContent(Node node) throws ParseException {

        getRequiredAttribute(node, "href", null);
        URL location = getURL(node, "href", base);

        String title = null;
        String description = null;
        IconDesc icon = null;

        // step through the elements
        Node child = node.getFirstChild();
        while (child != null) {
            String name = child.getNodeName();

            if ("title".equals(name)) {
                if (title != null && strict) {
                    throw new ParseException(R("PTwoTitles"));
                }
                title = getSpanText(child, false);
            } else if ("description".equals(name)) {
                if (description != null && strict) {
                    throw new ParseException(R("PTwoDescriptions"));
                }
                description = getSpanText(child, false);
            } else if ("icon".equals(name)) {
                if (icon != null && strict) {
                    throw new ParseException(R("PTwoIcons"));
                }
                icon = getIcon(child);
            }

            child = child.getNextSibling();
        }

        RelatedContentDesc relatedContent = new RelatedContentDesc(location);
        relatedContent.setDescription(description);
        relatedContent.setIconDesc(icon);
        relatedContent.setTitle(title);

        return relatedContent;

    }

    // other methods

    /**
     * Returns an array of substrings seperated by spaces (spaces
     * escaped with backslash do not separate strings).  This method
     * splits strings as per the spec except that it does replace
     * escaped other characters with their own value.
     */
    public String[] splitString(String source) {
        if (source == null)
            return new String[0];

        List<String> result = new ArrayList<String>();
        StringTokenizer st = new StringTokenizer(source, " ");
        StringBuilder part = new StringBuilder();
        while (st.hasMoreTokens()) {
            part.setLength(0);

            // tack together tokens joined by backslash
            while (true) {
                part.append(st.nextToken());

                if (st.hasMoreTokens() && part.charAt(part.length() - 1) == '\\')
                    part.setCharAt(part.length() - 1, ' '); // join with the space
                else
                    break; // bizarre while format gets \ at end of string right (no extra space added at end)
            }

            // delete \ quote chars
            for (int i = part.length(); i-- > 0;)
                // sweet syntax for reverse loop
                if (part.charAt(i) == '\\')
                    part.deleteCharAt(i--); // and skip previous char so \\ becomes \

            result.add(part.toString());
        }

        return result.toArray(new String[result.size()]);
    }

    /**
     * Returns the Locale object(s) from a node's locale attribute.
     *
     * @param node the node with a locale attribute
     */
    public Locale[] getLocales(Node node) {
        List<Locale> locales = new ArrayList<Locale>();
        String localeParts[] =
                splitString(getAttribute(node, "locale", ""));

        for (int i = 0; i < localeParts.length; i++) {
            Locale l = getLocale(localeParts[i]);
            if (l != null)
                locales.add(l);
        }

        return locales.toArray(new Locale[locales.size()]);
    }

    /**
     * Returns a Locale from a single locale.
     *
     * @param locale the locale string
     */
    public Locale getLocale(String localeStr) {
        if (localeStr.length() < 2)
            return null;

        String language = localeStr.substring(0, 2);
        String country = (localeStr.length() < 5) ? "" : localeStr.substring(3, 5);
        String variant = (localeStr.length() > 7) ? localeStr.substring(6) : "";

        // null is not allowed n locale but "" is
        return new Locale(language, country, variant);
    }

    // XML junk
    /**
     * Returns the implied text under a node, for example "text" in
     * "<description>text</description>".
     *
     * @param node the node with text under it
     * @throws ParseException if the JNLP file is invalid
     */
    public String getSpanText(Node node) throws ParseException {
        return getSpanText(node, true);
    }

    /**
     * Returns the implied text under a node, for example "text" in
     * "<description>text</description>". If preserveSpacing is false,
     * sequences of whitespace characters are turned into a single
     * space character.
     *
     * @param node the node with text under it
     * @param preserveSpacing if true, preserve whitespace
     * @throws ParseException if the JNLP file is invalid
     */
    public String getSpanText(Node node, boolean preserveSpacing)
            throws ParseException {
        if (node == null)
            return null;

        // NANO
        String val = node.getNodeValue();
        if (preserveSpacing) {
            return val;
        } else {
            if (val == null) {
                return null;
            } else {
                return val.replaceAll("\\s+", " ");
            }
        }

        /* TINY
        Node child = node.getFirstChild();

        if (child == null) {
            if (strict)
                // not sure if this is an error or whether "" is proper
                throw new ParseException("No text specified (node="+node.getNodeName()+")");
            else
                return "";
        }

        return child.getNodeValue();
        */
    }

    /**
     * Returns the first child node with the specified name.
     */
    public static Node getChildNode(Node node, String name) {
        Node[] result = getChildNodes(node, name);
        if (result.length == 0)
            return null;
        else
            return result[0];
    }

    /**
     * Returns all child nodes with the specified name.
     */
    public static Node[] getChildNodes(Node node, String name) {
        List<Node> result = new ArrayList<Node>();

        Node child = node.getFirstChild();
        while (child != null) {
            if (child.getNodeName().equals(name))
                result.add(child);
            child = child.getNextSibling();
        }

        return result.toArray(new Node[result.size()]);
    }

    /**
     * Returns a URL with a trailing / appended to it if there is no
     * trailing slash on the specifed URL.
     */
    private URL addSlash(URL source) {
        if (source == null)
            return null;

        if (!source.toString().endsWith("/")) {
            try {
                source = new URL(source.toString() + "/");
            } catch (MalformedURLException ex) {
            }
        }

        return source;
    }

    /**
     * Returns the same result as getURL except that a
     * ParseException is thrown if the attribute is null or empty.
     *
     * @param node the node
     * @param name the attribute containing an href
     * @param base the base URL
     * @throws ParseException if the JNLP file is invalid
     */
    public URL getRequiredURL(Node node, String name, URL base) throws ParseException {
        // probably should change "" to null so that url is always
        // required even if !strict
        getRequiredAttribute(node, name, "");

        return getURL(node, name, base);
    }

    /**
     * Returns a URL object from a href string relative to the
     * code base.  If the href denotes a relative URL, it must
     * reference a location that is a subdirectory of the
     * codebase.<p>
     *
     * @param node the node
     * @param name the attribute containing an href
     * @param base the base URL
     * @throws ParseException if the JNLP file is invalid
     */
    public URL getURL(Node node, String name, URL base) throws ParseException {
        String href = getAttribute(node, name, null);
        if (href == null)
            return null; // so that code can throw an exception if attribute was required

        try {
            if (base == null)
                return new URL(href);
            else {
                try {
                    return new URL(href);
                } catch (MalformedURLException ex) {
                    // is relative
                }

                URL result = new URL(base, href);

                // check for going above the codebase
                if (!result.toString().startsWith(base.toString()))
                    if (strict)
                        throw new ParseException(R("PUrlNotInCodebase", node.getNodeName(), href, base));

                return result;
            }

        } catch (MalformedURLException ex) {
            if (base == null)
                throw new ParseException(R("PBadNonrelativeUrl", node.getNodeName(), href));
            else
                throw new ParseException(R("PBadRelativeUrl", node.getNodeName(), href, base));
        }
    }

    /**
     * Returns a Version from the specified attribute and default
     * value.
     *
     * @param node the node
     * @param name the attribute
     * @param defaultValue default if no such attribute
     * @return a Version, or null if no such attribute and default is null
     */
    public Version getVersion(Node node, String name, String defaultValue) {
        String version = getAttribute(node, name, defaultValue);
        if (version == null)
            return null;
        else
            return new Version(version);
    }

    /**
     * Check that the VM args are valid and safe
     * @param vmArgs a string containing the args
     * @throws ParseException if the VM arguments are invalid or dangerous
     */
    private void checkVMArgs(String vmArgs) throws IllegalArgumentException {
        if (vmArgs == null) {
            return;
        }

        List<String> validArguments = Arrays.asList(getValidVMArguments());
        List<String> validStartingArguments = Arrays.asList(getValidStartingVMArguments());

        String[] arguments = vmArgs.split(" ");
        boolean argumentIsValid = false;
        for (String argument : arguments) {
            argumentIsValid = false;

            if (validArguments.contains(argument)) {
                argumentIsValid = true;
            } else {
                for (String validStartingArgument : validStartingArguments) {
                    if (argument.startsWith(validStartingArgument)) {
                        argumentIsValid = true;
                        break;
                    }
                }
            }

            if (!argumentIsValid) {
                throw new IllegalArgumentException(argument);
            }
        }

    }

    /**
     * Returns an array of valid (ie safe and supported) arguments for the JVM
     *
     * Based on http://java.sun.com/javase/6/docs/technotes/guides/javaws/developersguide/syntax.html
     */
    private String[] getValidVMArguments() {
        return new String[] {
                "-d32", /* use a 32-bit data model if available */
                "-client", /* to select the client VM */
                "-server", /* to select the server VM */
                "-verbose", /* enable verbose output */
                "-version", /* print product version and exit */
                "-showversion", /* print product version and continue */
                "-help", /* print this help message */
                "-X", /* print help on non-standard options */
                "-ea", /* enable assertions */
                "-enableassertions", /* enable assertions */
                "-da", /* disable assertions */
                "-disableassertions", /* disable assertions */
                "-esa", /* enable system assertions */
                "-enablesystemassertions", /* enable system assertions */
                "-dsa", /* disable system assertione */
                "-disablesystemassertions", /* disable system assertione */
                "-Xmixed", /* mixed mode execution (default) */
                "-Xint", /* interpreted mode execution only */
                "-Xnoclassgc", /* disable class garbage collection */
                "-Xincgc", /* enable incremental garbage collection */
                "-Xbatch", /* disable background compilation */
                "-Xprof", /* output cpu profiling data */
                "-Xdebug", /* enable remote debugging */
                "-Xfuture", /* enable strictest checks, anticipating future default */
                "-Xrs", /* reduce use of OS signals by Java/VM (see documentation) */
                "-XX:+ForceTimeHighResolution", /* use high resolution timer */
                "-XX:-ForceTimeHighResolution", /* use low resolution (default) */
        };
    }

    /**
     * Returns an array containing the starts of valid (ie safe and supported)
     * arguments for the JVM
     *
     * Based on http://java.sun.com/javase/6/docs/technotes/guides/javaws/developersguide/syntax.html
     */
    private String[] getValidStartingVMArguments() {
        return new String[] {
                "-ea", /* enable assertions for classes */
                "-enableassertions", /* enable assertions for classes */
                "-da", /* disable assertions for classes */
                "-disableassertions", /* disable assertions for classes */
                "-verbose", /* enable verbose output */
                "-Xms", /* set initial Java heap size */
                "-Xmx", /* set maximum Java heap size */
                "-Xss", /* set java thread stack size */
                "-XX:NewRatio", /* set Ratio of new/old gen sizes */
                "-XX:NewSize", /* set initial size of new generation */
                "-XX:MaxNewSize", /* set max size of new generation */
                "-XX:PermSize", /* set initial size of permanent gen */
                "-XX:MaxPermSize", /* set max size of permanent gen */
                "-XX:MaxHeapFreeRatio", /* heap free percentage (default 70) */
                "-XX:MinHeapFreeRatio", /* heap free percentage (default 40) */
                "-XX:UseSerialGC", /* use serial garbage collection */
                "-XX:ThreadStackSize", /* thread stack size (in KB) */
                "-XX:MaxInlineSize", /* set max num of bytecodes to inline */
                "-XX:ReservedCodeCacheSize", /* Reserved code cache size (bytes) */
                "-XX:MaxDirectMemorySize",

        };
    }

    /**
     * Returns the same result as getAttribute except that if strict
     * mode is enabled or the default value is null a parse
     * exception is thrown instead of returning the default value.
     *
     * @param node the node
     * @param name the attribute
     * @param defaultValue default value
     * @throws ParseException if the attribute does not exist or is empty
     */
    public String getRequiredAttribute(Node node, String name, String defaultValue) throws ParseException {
        String result = getAttribute(node, name, null);

        if (result == null || result.length() == 0)
            if (strict || defaultValue == null)
                throw new ParseException(R("PNeedsAttribute", node.getNodeName(), name));

        if (result == null)
            return defaultValue;
        else
            return result;
    }

    /**
     * Retuns an attribute or the specified defaultValue if there is
     * no such attribute.
     *
     * @param node the node
     * @param name the attribute
     * @param defaultValue default if no such attribute
     */
    public String getAttribute(Node node, String name, String defaultValue) {
        // SAX
        // String result = ((Element) node).getAttribute(name);
        String result = node.getAttribute(name);

        if (result == null || result.length() == 0)
            return defaultValue;

        return result;
    }

    /**
     * Return the root node from the XML document in the specified
     * input stream.
     *
     * @throws ParseException if the JNLP file is invalid
     */
    public static Node getRootNode(InputStream input) throws ParseException {
        try {
            /* SAX
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            factory.setValidating(false);
            factory.setNamespaceAware(true);
            DocumentBuilder builder = factory.newDocumentBuilder();
            builder.setErrorHandler(errorHandler);

            Document doc = builder.parse(input);
            return doc.getDocumentElement();
            */

            /* TINY
            Node document = new Node(TinyParser.parseXML(input));
            Node jnlpNode = getChildNode(document, "jnlp"); // skip comments
            */

            //A BufferedInputStream is used to allow marking and reseting
            //of a stream.
            BufferedInputStream bs = new BufferedInputStream(input);

            /* NANO */
            final XMLElement xml = new XMLElement();
            final PipedInputStream pin = new PipedInputStream();
            final PipedOutputStream pout = new PipedOutputStream(pin);
            final InputStreamReader isr = new InputStreamReader(bs, getEncoding(bs));
            // Clean the jnlp xml file of all comments before passing
            // it to the parser.
            new Thread(
                    new Runnable() {
                        public void run() {
                            (new XMLElement()).sanitizeInput(isr, pout);
                            try {
                                pout.close();
                            } catch (IOException ioe) {
                                ioe.printStackTrace();
                            }
                        }
                    }).start();
            xml.parseFromReader(new InputStreamReader(pin));
            Node jnlpNode = new Node(xml);
            return jnlpNode;
        } catch (Exception ex) {
            throw new ParseException(R("PBadXML"), ex);
        }
    }

    /**
     * Returns the name of the encoding used in this InputStream.
     *
     * @param input the InputStream
     * @return a String representation of encoding
     */
    private static String getEncoding(InputStream input) throws IOException {
        //Fixme: This only recognizes UTF-8, UTF-16, and
        //UTF-32, which is enough to parse the prolog portion of xml to
        //find out the exact encoding (if it exists). The reason being
        //there could be other encodings, such as ISO 8859 which is 8-bits
        //but it supports latin characters.
        //So what needs to be done is to parse the prolog and retrieve
        //the exact encoding from it.

        int[] s = new int[4];
        String encoding = "UTF-8";

        //Determine what the first four bytes are and store
        //them into an int array.
        input.mark(4);
        for (int i = 0; i < 4; i++) {
            s[i] = input.read();
        }
        input.reset();

        //Set the encoding base on what the first four bytes of the
        //inputstream turn out to be (following the information from
        //www.w3.org/TR/REC-xml/#sec-guessing).
        if (s[0] == 255) {
            if (s[1] == 254) {
                if (s[2] != 0 || s[3] != 0) {
                    encoding = "UnicodeLittle";
                } else {
                    encoding = "X-UTF-32LE-BOM";
                }
            }
        } else if (s[0] == 254 && s[1] == 255 && (s[2] != 0 ||
                s[3] != 0)) {
            encoding = "UTF-16";

        } else if (s[0] == 0 && s[1] == 0 && s[2] == 254 &&
                s[3] == 255) {
            encoding = "X-UTF-32BE-BOM";

        } else if (s[0] == 0 && s[1] == 0 && s[2] == 0 &&
                s[3] == 60) {
            encoding = "UTF-32BE";

        } else if (s[0] == 60 && s[1] == 0 && s[2] == 0 &&
                s[3] == 0) {
            encoding = "UTF-32LE";

        } else if (s[0] == 0 && s[1] == 60 && s[2] == 0 &&
                s[3] == 63) {
            encoding = "UTF-16BE";
        } else if (s[0] == 60 && s[1] == 0 && s[2] == 63 &&
                s[3] == 0) {
            encoding = "UTF-16LE";
        }

        return encoding;
    }

}