| // NamespaceSupport.java - generic Namespace support for SAX. |
| // http://www.saxproject.org |
| // Written by David Megginson |
| // This class is in the Public Domain. NO WARRANTY! |
| // $Id: NamespaceSupport.java,v 1.15 2004/04/26 17:34:35 dmegginson Exp $ |
| |
| using J2N.Text; |
| using System; |
| using System.Collections; |
| using System.Collections.Generic; |
| using System.Linq; |
| |
| namespace Sax.Helpers |
| { |
| /// <summary> |
| /// Encapsulate Namespace logic for use by applications using SAX, |
| /// or internally by SAX drivers. |
| /// <para/> |
| /// <em>This module, both source code and documentation, is in the |
| /// Public Domain, and comes with <strong>NO WARRANTY</strong>.</em> |
| /// See <a href='http://www.saxproject.org'>http://www.saxproject.org</a> |
| /// for further information. |
| /// <para/> |
| /// This class encapsulates the logic of Namespace processing: it |
| /// tracks the declarations currently in force for each context and |
| /// automatically processes qualified XML names into their Namespace |
| /// parts; it can also be used in reverse for generating XML qnames |
| /// from Namespaces. |
| /// <para/> |
| /// Namespace support objects are reusable, but the reset method |
| /// must be invoked between each session. |
| /// <para/>Here is a simple session: |
| /// <code> |
| /// string parts[] = new string[3]; |
| /// NamespaceSupport support = new NamespaceSupport(); |
| /// support.PushContext(); |
| /// support.DeclarePrefix("", "http://www.w3.org/1999/xhtml"); |
| /// support.DeclarePrefix("dc", "http://www.purl.org/dc#"); |
| /// parts = support.ProcessName("p", parts, false); |
| /// Console.WriteLine("Namespace URI: " + parts[0]); |
| /// Console.WriteLine("Local name: " + parts[1]); |
| /// Console.WriteLine("Raw name: " + parts[2]); |
| /// parts = support.ProcessName("dc:title", parts, false); |
| /// Console.WriteLine("Namespace URI: " + parts[0]); |
| /// Console.WriteLine("Local name: " + parts[1]); |
| /// Console.WriteLine("Raw name: " + parts[2]); |
| /// support.PopContext(); |
| /// </code> |
| /// <para/> |
| /// Note that this class is optimized for the use case where most |
| /// elements do not contain Namespace declarations: if the same |
| /// prefix/URI mapping is repeated for each context (for example), this |
| /// class will be somewhat less efficient. |
| /// <para/> |
| /// Although SAX drivers (parsers) may choose to use this class to |
| /// implement namespace handling, they are not required to do so. |
| /// Applications must track namespace information themselves if they |
| /// want to use namespace information. |
| /// </summary> |
| public class NamespaceSupport |
| { |
| /// <summary> |
| /// The XML Namespace URI as a constant. |
| /// The value is <c>http://www.w3.org/XML/1998/namespace</c> |
| /// as defined in the "Namespaces in XML" * recommendation. |
| /// <para>This is the Namespace URI that is automatically mapped to the "xml" prefix.</para> |
| /// </summary> |
| public const string XMLNS = "http://www.w3.org/XML/1998/namespace"; |
| |
| /// <summary> |
| /// The namespace declaration URI as a constant. |
| /// The value is <c>http://www.w3.org/xmlns/2000/</c>, as defined |
| /// in a backwards-incompatible erratum to the "Namespaces in XML" |
| /// recommendation. Because that erratum postdated SAX2, SAX2 defaults |
| /// to the original recommendation, and does not normally use this URI. |
| /// <para/> |
| /// This is the Namespace URI that is optionally applied to |
| /// <em>xmlns</em> and <em>xmlns:*</em> attributes, which are used to |
| /// declare namespaces. |
| /// </summary> |
| /// <seealso cref="SetNamespaceDeclUris(bool)" /> |
| /// <seealso cref="IsNamespaceDeclUris" /> |
| //// |
| public const string NSDECL = "http://www.w3.org/xmlns/2000/"; |
| |
| |
| //////////////////////////////////////////////////////////////////// |
| // Constructor. |
| //////////////////////////////////////////////////////////////////// |
| |
| /// <summary> |
| /// Create a new Namespace support object. |
| /// </summary> |
| public NamespaceSupport() |
| { |
| Reset(); |
| } |
| |
| //////////////////////////////////////////////////////////////////// |
| // Context management. |
| //////////////////////////////////////////////////////////////////// |
| |
| /// <summary> |
| /// Reset this Namespace support object for reuse. |
| /// <para/> |
| /// It is necessary to invoke this method before reusing the |
| /// Namespace support object for a new session. If namespace |
| /// declaration URIs are to be supported, that flag must also |
| /// be set to a non-default value. |
| /// </summary> |
| /// <seealso cref="SetNamespaceDeclUris" /> |
| public void Reset() |
| { |
| contexts = new Context[32]; |
| namespaceDeclUris = false; |
| contextPos = 0; |
| contexts[contextPos] = currentContext = new Context(this); |
| currentContext.DeclarePrefix("xml", XMLNS); |
| } |
| |
| /// <summary> |
| /// Start a new Namespace context. |
| /// The new context will automatically inherit |
| /// the declarations of its parent context, but it will also keep |
| /// track of which declarations were made within this context. |
| /// <para/> |
| /// Event callback code should start a new context once per element. |
| /// This means being ready to call this in either of two places. |
| /// For elements that don't include namespace declarations, the |
| /// <see cref="IContentHandler.StartElement(string, string, string, IAttributes)"/> callback is the right place. |
| /// For elements with such a declaration, it'd done in the first |
| /// <see cref="IContentHandler.StartPrefixMapping(string, string)"/> callback. |
| /// A boolean flag can be used to |
| /// track whether a context has been started yet. When either of |
| /// those methods is called, it checks the flag to see if a new context |
| /// needs to be started. If so, it starts the context and sets the |
| /// flag. After <see cref="IContentHandler.StartElement(string, string, string, IAttributes)"/> |
| /// does that, it always clears the flag. |
| /// <para/> |
| /// Normally, SAX drivers would push a new context at the beginning |
| /// of each XML element. Then they perform a first pass over the |
| /// attributes to process all namespace declarations, making |
| /// <see cref="IContentHandler.StartPrefixMapping(string, string)"/> callbacks. |
| /// Then a second pass is made, to determine the namespace-qualified |
| /// names for all attributes and for the element name. |
| /// Finally all the information for the |
| /// <see cref="IContentHandler.StartElement(string, string, string, IAttributes)"/> callback is available, |
| /// so it can then be made. |
| /// <para/> |
| /// The Namespace support object always starts with a base context |
| /// already in force: in this context, only the "xml" prefix is |
| /// declared. |
| /// </summary> |
| /// <seealso cref="IContentHandler" /> |
| /// <seealso cref="PopContext()" /> |
| public void PushContext() |
| { |
| int max = contexts.Length; |
| |
| contexts[contextPos].declsOK = false; |
| contextPos++; |
| |
| // Extend the array if necessary |
| if (contextPos >= max) |
| { |
| var newContexts = new Context[max * 2]; |
| Array.Copy(contexts, 0, newContexts, 0, max); |
| max *= 2; |
| contexts = newContexts; |
| } |
| |
| // Allocate the context if necessary. |
| currentContext = contexts[contextPos]; |
| if (currentContext == null) |
| { |
| contexts[contextPos] = currentContext = new Context(this); |
| } |
| |
| // Set the parent, if any. |
| if (contextPos > 0) |
| { |
| currentContext.SetParent(contexts[contextPos - 1]); |
| } |
| } |
| |
| /// <summary> |
| /// Revert to the previous Namespace context. |
| /// <para/> |
| /// Normally, you should pop the context at the end of each |
| /// XML element. After popping the context, all Namespace prefix |
| /// mappings that were previously in force are restored. |
| /// <para/> |
| /// You must not attempt to declare additional Namespace |
| /// prefixes after popping a context, unless you push another |
| /// context first. |
| /// </summary> |
| /// <seealso cref="PushContext()" /> |
| public void PopContext() |
| { |
| contexts[contextPos].Clear(); |
| contextPos--; |
| if (contextPos < 0) |
| { |
| throw new InvalidOperationException(); |
| } |
| currentContext = contexts[contextPos]; |
| } |
| |
| //////////////////////////////////////////////////////////////////// |
| // Operations within a context. |
| //////////////////////////////////////////////////////////////////// |
| |
| /// <summary> |
| /// Declare a Namespace prefix. All prefixes must be declared |
| /// before they are referenced. For example, a SAX driver (parser) |
| /// would scan an element's attributes |
| /// in two passes: first for namespace declarations, |
| /// then a second pass using <see cref="ProcessName" /> to |
| /// interpret prefixes against (potentially redefined) prefixes. |
| /// <para/> |
| /// This method declares a prefix in the current Namespace |
| /// context; the prefix will remain in force until this context |
| /// is popped, unless it is shadowed in a descendant context. |
| /// <para/> |
| /// To declare the default element Namespace, use the empty string as |
| /// the prefix. |
| /// <para/> |
| /// Note that you must <em>not</em> declare a prefix after |
| /// you've pushed and popped another Namespace context, or |
| /// treated the declarations phase as complete by processing |
| /// a prefixed name. |
| /// <para/> |
| /// Note that there is an asymmetry in this library: <see cref="GetPrefix" /> will not return the "" prefix, |
| /// even if you have declared a default element namespace. |
| /// To check for a default namespace, |
| /// you have to look it up explicitly using <see cref="GetUri" />. |
| /// This asymmetry exists to make it easier to look up prefixes |
| /// for attribute names, where the default prefix is not allowed. |
| /// </summary> |
| /// <param name="prefix"> |
| /// The prefix to declare, or the empty string to |
| /// indicate the default element namespace. This may never have |
| /// the value "xml" or "xmlns". |
| /// </param> |
| /// <param name="uri"> |
| /// The Namespace URI to associate with the prefix. |
| /// </param> |
| /// <returns><c>true</c> if the prefix was legal, <c>false</c> otherwise</returns> |
| /// <seealso cref="ProcessName(string, string[], bool)" /> |
| /// <seealso cref="GetUri(string)" /> |
| /// <seealso cref="GetPrefix(string)" /> |
| public bool DeclarePrefix(string prefix, string uri) |
| { |
| if (prefix.Equals("xml", StringComparison.Ordinal) || prefix.Equals("xmlns", StringComparison.Ordinal)) |
| { |
| return false; |
| } |
| currentContext.DeclarePrefix(prefix, uri); |
| return true; |
| } |
| |
| /// <summary> |
| /// Process a raw XML qualified name, after all declarations in the |
| /// current context have been handled by <see cref="DeclarePrefix" />. |
| /// <para> |
| /// This method processes a raw XML qualified name in the |
| /// current context by removing the prefix and looking it up among |
| /// the prefixes currently declared. The return value will be the |
| /// array supplied by the caller, filled in as follows: |
| /// </para> |
| /// <list type="table"> |
| /// <item> |
| /// <term>parts[0]</term> |
| /// <description>The Namespace URI, or an empty string if none is in use.</description> |
| /// </item> |
| /// <item> |
| /// <term>parts[1]</term> |
| /// <description>The local name (without prefix).</description> |
| /// </item> |
| /// <item> |
| /// <term>parts[2]</term> |
| /// <description>The original raw name.</description> |
| /// </item> |
| /// </list> |
| /// <para> |
| /// All of the strings in the array will be internalized. If |
| /// the raw name has a prefix that has not been declared, then |
| /// the return value will be null. |
| /// </para> |
| /// <para> |
| /// Note that attribute names are processed differently than |
| /// element names: an unprefixed element name will receive the |
| /// default Namespace (if any), while an unprefixed attribute name |
| /// will not. |
| /// </para> |
| /// </summary> |
| /// <param name="qName"> |
| /// The XML qualified name to be processed. |
| /// </param> |
| /// <param name="parts"> |
| /// An array supplied by the caller, capable of |
| /// holding at least three members. |
| /// </param> |
| /// <param name="isAttribute"> |
| /// A flag indicating whether this is an |
| /// attribute name (true) or an element name (false). |
| /// </param> |
| /// <returns> |
| /// The supplied array holding three internalized strings |
| /// representing the Namespace URI (or empty string), the |
| /// local name, and the XML qualified name; or null if there |
| /// is an undeclared prefix. |
| /// </returns> |
| /// <seealso cref="DeclarePrefix" /> |
| /// <seealso cref="StringExtensions.Intern(string)" /> |
| public string[] ProcessName(string qName, string[] parts, bool isAttribute) |
| { |
| string[] myParts = currentContext.ProcessName(qName, isAttribute); |
| if (myParts == null) |
| { |
| return null; |
| } |
| parts[0] = myParts[0]; |
| parts[1] = myParts[1]; |
| parts[2] = myParts[2]; |
| return parts; |
| } |
| |
| /// <summary> |
| /// Look up a prefix and get the currently-mapped Namespace URI. |
| /// <para> |
| /// This method looks up the prefix in the current context. |
| /// Use the empty string ("") for the default Namespace. |
| /// </para> |
| /// </summary> |
| /// <param name="prefix"> |
| /// The prefix to look up. |
| /// </param> |
| /// <returns> |
| /// The associated Namespace URI, or null if the prefix |
| /// is undeclared in this context. |
| /// </returns> |
| /// <seealso cref="GetPrefix" /> |
| /// <seealso cref="GetPrefixes()" /> |
| public string GetUri(string prefix) |
| { |
| return currentContext.GetURI(prefix); |
| } |
| |
| /// <summary> |
| /// Return an enumeration of all prefixes whose declarations are |
| /// active in the current context. |
| /// This includes declarations from parent contexts that have |
| /// not been overridden. |
| /// <para> |
| /// <strong>Note:</strong> if there is a default prefix, it will not be |
| /// returned in this enumeration; check for the default prefix |
| /// using the <see cref="GetUri" /> with an argument of "". |
| /// </para> |
| /// </summary> |
| /// <returns>An enumeration of prefixes (never empty).</returns> |
| /// <seealso cref="GetDeclaredPrefixes" /> |
| /// <seealso cref="GetUri" /> |
| public IEnumerable GetPrefixes() |
| { |
| return currentContext.GetPrefixes(); |
| } |
| |
| /// <summary> |
| /// Return one of the prefixes mapped to a Namespace URI. |
| /// <para> |
| /// If more than one prefix is currently mapped to the same |
| /// URI, this method will make an arbitrary selection; if you |
| /// want all of the prefixes, use the <see cref="GetPrefixes()" /> |
| /// method instead. |
| /// </para> |
| /// <para> |
| /// <strong>Note:</strong> this will never return the empty (default) prefix; |
| /// to check for a default prefix, use the <see cref="GetUri" /> |
| /// method with an argument of "". |
| /// </para> |
| /// </summary> |
| /// <param name="uri"> |
| /// the namespace URI |
| /// </param> |
| /// <returns> |
| /// one of the prefixes currently mapped to the URI supplied, |
| /// or null if none is mapped or if the URI is assigned to |
| /// the default namespace |
| /// </returns> |
| /// <seealso cref="GetPrefixes(string)" /> |
| /// <seealso cref="GetUri" /> |
| public string GetPrefix(string uri) |
| { |
| return currentContext.GetPrefix(uri); |
| } |
| |
| /// <summary> |
| /// Return an enumeration of all prefixes for a given URI whose |
| /// declarations are active in the current context. |
| /// This includes declarations from parent contexts that have |
| /// not been overridden. |
| /// <para> |
| /// This method returns prefixes mapped to a specific Namespace |
| /// URI. The xml: prefix will be included. If you want only one |
| /// prefix that's mapped to the Namespace URI, and you don't care |
| /// which one you get, use the <see cref="GetPrefix" /> |
| /// method instead. |
| /// </para> |
| /// <para> |
| /// <strong>Note:</strong> the empty (default) prefix is <em>never</em> included |
| /// in this enumeration; to check for the presence of a default |
| /// Namespace, use the <see cref="GetUri" /> method with an |
| /// argument of "". |
| /// </para> |
| /// </summary> |
| /// <param name="uri"> |
| /// The Namespace URI. |
| /// </param> |
| /// <returns>An enumeration of prefixes (never empty).</returns> |
| /// <seealso cref="GetPrefix" /> |
| /// <seealso cref="GetDeclaredPrefixes" /> |
| /// <seealso cref="GetUri" /> |
| public IEnumerable GetPrefixes(string uri) |
| { |
| var prefixes = new ArrayList(); |
| // LUCENENET NOTE: IEnumerator is not disposable |
| IEnumerator allPrefixes = GetPrefixes().GetEnumerator(); |
| while (allPrefixes.MoveNext()) |
| { |
| var prefix = (string)allPrefixes.Current; |
| if (uri.Equals(GetUri(prefix), StringComparison.Ordinal)) |
| { |
| prefixes.Add(prefix); |
| } |
| } |
| return prefixes; |
| } |
| |
| /// <summary> |
| /// Return an enumeration of all prefixes declared in this context. |
| /// <para> |
| /// The empty (default) prefix will be included in this |
| /// enumeration; note that this behaviour differs from that of |
| /// <see cref="GetPrefix" /> and <see cref="GetPrefixes()" />. |
| /// </para> |
| /// </summary> |
| /// <returns> |
| /// An enumeration of all prefixes declared in this |
| /// context. |
| /// </returns> |
| /// <seealso cref="GetPrefixes()" /> |
| /// <seealso cref="GetUri" /> |
| public IEnumerable GetDeclaredPrefixes() |
| { |
| return currentContext.GetDeclaredPrefixes(); |
| } |
| |
| /// <summary> |
| /// Controls whether namespace declaration attributes are placed |
| /// into the <see cref="NSDECL" /> namespace |
| /// by <see cref="ProcessName" />. This may only be |
| /// changed before any contexts have been pushed. |
| /// </summary> |
| /// <exception cref="InvalidOperationException"> |
| /// when attempting to set this |
| /// after any context has been pushed. |
| /// </exception> |
| public void SetNamespaceDeclUris(bool value) |
| { |
| if (contextPos != 0) |
| { |
| throw new InvalidOperationException(); |
| } |
| if (value == namespaceDeclUris) |
| { |
| return; |
| } |
| namespaceDeclUris = value; |
| if (value) |
| { |
| currentContext.DeclarePrefix("xmlns", NSDECL); |
| } |
| else |
| { |
| contexts[contextPos] = currentContext = new Context(this); |
| currentContext.DeclarePrefix("xml", XMLNS); |
| } |
| } |
| |
| /// <summary> |
| /// Returns true if namespace declaration attributes are placed into |
| /// a namespace. This behavior is not the default. |
| /// </summary> |
| public bool IsNamespaceDeclUris |
| { |
| get { return namespaceDeclUris; } |
| } |
| |
| //////////////////////////////////////////////////////////////////// |
| // Internal state. |
| //////////////////////////////////////////////////////////////////// |
| |
| private Context[] contexts; |
| private Context currentContext; |
| private int contextPos; |
| private bool namespaceDeclUris; |
| |
| //////////////////////////////////////////////////////////////////// |
| // Internal classes. |
| //////////////////////////////////////////////////////////////////// |
| |
| /// <summary> |
| /// Internal class for a single Namespace context. |
| /// </summary> |
| /// <remarks> |
| /// This module caches and reuses Namespace contexts, |
| /// so the number allocated |
| /// will be equal to the element depth of the document, not to the total |
| /// number of elements (i.e. 5-10 rather than tens of thousands). |
| /// Also, data structures used to represent contexts are shared when |
| /// possible (child contexts without declarations) to further reduce |
| /// the amount of memory that's consumed. |
| /// </remarks> |
| internal sealed class Context |
| { |
| private readonly NamespaceSupport outerInstance; |
| |
| /// <summary> |
| /// Create the root-level Namespace context. |
| /// </summary> |
| public Context(NamespaceSupport outerInstance) |
| { |
| this.outerInstance = outerInstance; |
| CopyTables(); |
| } |
| |
| /// <summary> |
| /// (Re)set the parent of this Namespace context. |
| /// The context must either have been freshly constructed, |
| /// or must have been cleared. |
| /// </summary> |
| /// <param name="parent">The parent Namespace context object.</param> |
| public void SetParent(Context parent) |
| { |
| this.parent = parent; |
| declarations = null; |
| prefixTable = parent.prefixTable; |
| uriTable = parent.uriTable; |
| elementNameTable = parent.elementNameTable; |
| attributeNameTable = parent.attributeNameTable; |
| defaultNs = parent.defaultNs; |
| declSeen = false; |
| declsOK = true; |
| } |
| |
| /// <summary> |
| /// Makes associated state become collectible, |
| /// invalidating this context. |
| /// <see cref="SetParent(Context)"/> must be called before |
| /// this context may be used again. |
| /// </summary> |
| public void Clear() |
| { |
| parent = null; |
| prefixTable = null; |
| uriTable = null; |
| elementNameTable = null; |
| attributeNameTable = null; |
| defaultNs = null; |
| } |
| |
| /// <summary> |
| /// Declare a Namespace prefix for this context. |
| /// </summary> |
| /// <param name="prefix">The prefix to declare.</param> |
| /// <param name="uri">The associated Namespace URI.</param> |
| /// <seealso cref="DeclarePrefix(string, string)"/> |
| public void DeclarePrefix(string prefix, string uri) |
| { |
| // Lazy processing... |
| if (!declsOK) |
| { |
| throw new InvalidOperationException("can't declare any more prefixes in this context"); |
| } |
| if (!declSeen) |
| { |
| CopyTables(); |
| } |
| if (declarations == null) |
| { |
| declarations = new List<string>(); |
| } |
| |
| prefix = prefix.Intern(); |
| uri = uri.Intern(); |
| if ("".Equals(prefix, StringComparison.Ordinal)) |
| { |
| if ("".Equals(uri, StringComparison.Ordinal)) |
| { |
| defaultNs = null; |
| } |
| else |
| { |
| defaultNs = uri; |
| } |
| } |
| else |
| { |
| prefixTable.Add(prefix, uri); |
| uriTable.Add(uri, prefix); // may wipe out another prefix |
| } |
| declarations.Add(prefix); |
| } |
| |
| /// <summary> |
| /// Process an XML qualified name in this context. |
| /// </summary> |
| /// <param name="qName">The XML qualified name.</param> |
| /// <param name="isAttribute">true if this is an attribute name.</param> |
| /// <returns>An array of three strings containing the |
| /// URI part (or empty string), the local part, |
| /// and the raw name, all internalized, or null |
| /// if there is an undeclared prefix.</returns> |
| /// <seealso cref="DeclarePrefix(string, string)"/> |
| internal string[] ProcessName(string qName, bool isAttribute) |
| { |
| string[] name; |
| IDictionary<string, string[]> table; |
| |
| // detect errors in call sequence |
| declsOK = false; |
| |
| // Select the appropriate table. |
| if (isAttribute) |
| { |
| table = attributeNameTable; |
| } |
| else |
| { |
| table = elementNameTable; |
| } |
| |
| // Start by looking in the cache, and |
| // return immediately if the name |
| // is already known in this content |
| if (table.TryGetValue(qName, out string[] value)) |
| { |
| return value; |
| } |
| |
| // We haven't seen this name in this |
| // context before. Maybe in the parent |
| // context, but we can't assume prefix |
| // bindings are the same. |
| name = new string[3]; |
| name[2] = qName.Intern(); |
| int index = qName.IndexOf(':'); |
| |
| // No prefix. |
| if (index == -1) |
| { |
| if (isAttribute) |
| { |
| if (qName == "xmlns" && outerInstance.namespaceDeclUris) |
| { |
| name[0] = NSDECL; |
| } |
| else |
| { |
| name[0] = ""; |
| } |
| } |
| else if (defaultNs == null) |
| { |
| name[0] = ""; |
| } |
| else |
| { |
| name[0] = defaultNs; |
| } |
| name[1] = name[2]; |
| } |
| |
| // Prefix |
| else |
| { |
| string prefix = qName.Substring(0, index); |
| string local = qName.Substring(index + 1); |
| string uri = null; |
| if ("".Equals(prefix, StringComparison.Ordinal)) |
| { |
| uri = defaultNs; |
| } |
| else if (prefixTable.ContainsKey(prefix)) |
| { |
| uri = (string)prefixTable[prefix]; |
| } |
| if (uri == null || (!isAttribute && "xmlns".Equals(prefix, StringComparison.Ordinal))) |
| { |
| return null; |
| } |
| name[0] = uri; |
| name[1] = local.Intern(); |
| } |
| |
| // Save in the cache for future use. |
| // (Could be shared with parent context...) |
| table.Add(name[2], name); |
| return name; |
| } |
| |
| /// <summary> |
| /// Look up the URI associated with a prefix in this context. |
| /// </summary> |
| /// <param name="prefix">The prefix to look up.</param> |
| /// <returns>The associated Namespace URI, or null if none is declared.</returns> |
| /// <seealso cref="NamespaceSupport.GetUri(string)"/> |
| internal string GetURI(string prefix) |
| { |
| if ("".Equals(prefix, StringComparison.Ordinal)) |
| { |
| return defaultNs; |
| } |
| if (prefixTable == null) |
| { |
| return null; |
| } |
| if (prefixTable.ContainsKey(prefix)) |
| { |
| return (string)prefixTable[prefix]; |
| } |
| return null; |
| } |
| |
| /// <summary> |
| /// Look up one of the prefixes associated with a URI in this context. |
| /// <para/> |
| /// Since many prefixes may be mapped to the same URI, the return value may be unreliable. |
| /// </summary> |
| /// <param name="uri">The URI to look up.</param> |
| /// <returns>The associated prefix, or null if none is declared.</returns> |
| /// <seealso cref="NamespaceSupport.GetPrefix(string)"/> |
| internal string GetPrefix(string uri) |
| { |
| if (uriTable == null) |
| { |
| return null; |
| } |
| if (uriTable.ContainsKey(uri)) |
| { |
| return (string)uriTable[uri]; |
| } |
| return null; |
| } |
| |
| /// <summary> |
| /// Return an enumeration of prefixes declared in this context. |
| /// </summary> |
| /// <returns>An enumeration of prefixes (possibly empty).</returns> |
| /// <seealso cref="NamespaceSupport.GetDeclaredPrefixes()"/> |
| internal IEnumerable GetDeclaredPrefixes() |
| { |
| if (declarations == null) |
| { |
| return Enumerable.Empty<object>(); |
| } |
| return declarations; |
| } |
| |
| /// <summary> |
| /// Return an enumeration of all prefixes currently in force. |
| /// <para/> |
| /// The default prefix, if in force, is <em>not</em> |
| /// returned, and will have to be checked for separately. |
| /// </summary> |
| /// <returns>An enumeration of prefixes (never empty).</returns> |
| /// <seealso cref="NamespaceSupport.GetPrefixes()"/> |
| internal IEnumerable GetPrefixes() |
| { |
| if (prefixTable == null) |
| { |
| return Enumerable.Empty<object>(); |
| } |
| return prefixTable.Keys; |
| } |
| |
| //////////////////////////////////////////////////////////////// |
| // Internal methods. |
| //////////////////////////////////////////////////////////////// |
| |
| /// <summary> |
| /// Copy on write for the internal tables in this context. |
| /// <para/> |
| /// This class is optimized for the normal case where most |
| /// elements do not contain Namespace declarations. |
| /// </summary> |
| private void CopyTables() |
| { |
| if (prefixTable != null) |
| { |
| prefixTable = (Hashtable)prefixTable.Clone(); |
| } |
| else |
| { |
| prefixTable = new Hashtable(); |
| } |
| if (uriTable != null) |
| { |
| uriTable = (Hashtable)uriTable.Clone(); |
| } |
| else |
| { |
| uriTable = new Hashtable(); |
| } |
| elementNameTable = new Dictionary<string, string[]>(); |
| attributeNameTable = new Dictionary<string, string[]>(); |
| declSeen = true; |
| } |
| |
| //////////////////////////////////////////////////////////////// |
| // Protected state. |
| //////////////////////////////////////////////////////////////// |
| |
| private Hashtable prefixTable; |
| private Hashtable uriTable; |
| private IDictionary<string, string[]> elementNameTable; |
| private IDictionary<string, string[]> attributeNameTable; |
| private string defaultNs; |
| internal bool declsOK = true; |
| |
| //////////////////////////////////////////////////////////////// |
| // Internal state. |
| //////////////////////////////////////////////////////////////// |
| |
| private IList<string> declarations; |
| private bool declSeen; |
| private Context parent; |
| } |
| } |
| } |
