balxml_prefixstack

Detailed Description

Outline

• Purpose
• Classes
• Description
  • Usage
    • Example 1: Basic Usage

Purpose

Provide a unique integer ID for each XML namespace.

Classes

• balxml::PrefixStack: stack of (namespace prefix, unique integer ID) pairs

See also

balxml_namespaceregistry

Description

balxml::PrefixStack keeps a collection of pairs - the prefix string and the integer associated with each namespace uri. Registration of prefix with namespace works similar to "pushing in stack", i.e., it hides the previous prefix<->namespaces association. Deregistration of prefix removes the current association and opens the previous association of given prefix.

It is safe to read or modify multiple instances of balxml::PrefixStack simultaneously, each from a separate thread. It is safe to read a single instance of balxml::PrefixStack from multiple threads, provided no thread is modifying it at the same time. It is not safe to read or modify an instance of balxml::PrefixStack from one thread while any other thread is modifying the same instance. Modifying a balxml::PrefixStack objects may modify the referenced balxml::NamespaceRegistry object. It is not safe to read or modify an instance of balxml::PrefixStack from one thread while any other thread is (directly or indirectly) modifying the referenced balxml::NamespaceRegistry.

Usage

This section illustrates intended use of this component.

Example 1: Basic Usage

In this example we demonstrate registering several prefixes with different namespaces and printing them along with their ID.

  balxml::NamespaceRegistry namespaces;
  balxml::PrefixStack    prefixes(namespaces, allocator);
 
  bsl::string uri1 = "http://www.google.com";
  bsl::string uri2 = "http://www.yahoo.com";
  bsl::string uri3 = "http://www.hotmail.com";
  bsl::string uri4 = "http://www.msn.com";
 
  bsl::string prefix1 = "a";
  bsl::string prefix2 = "b";
  bsl::string prefix3 = "c";
 
  int namespaceId1 = prefixes.pushPrefix(prefix1, uri1);
  int namespaceId2 = prefixes.pushPrefix(prefix2, uri2);
  int namespaceId3 = prefixes.pushPrefix(prefix3, uri3);
 
  bsl::cout << prefix1 << ":" << namespaceId1 << bsl::endl;
  bsl::cout << prefix2 << ":" << namespaceId2 << bsl::endl;
  bsl::cout << prefix3 << ":" << namespaceId3 << bsl::endl;
 
  int namespaceId4 = prefixes.pushPrefix(prefix1, uri4);
 
  bsl::cout << prefix1 << ":" << namespaceId1 << bsl::endl;
 
  prefixes.popPrefix(prefix1);
 
  bsl::cout << prefix1 << ":" << namespaceId1 << bsl::endl;