Changes between Version 7 and Version 8 of XML/SAX

Timestamp:

Jan 28, 2011, 6:04:23 AM (11 years ago)

Author:

vadim.godunko

Comment:

--

XML/SAX

@@ -39 +39 @@
 || XML.SAX.Output_Destinations || Not implemented yet ||
 || XML.SAX.Parse_Exceptions || Provides implementation of object to represent errors in the document ||
-|| XML.SAX.Pretty_Writers || Provides implementation of SAX writer to output XML. Not implemented yet ||
+|| XML.SAX.Pretty_Writers || Provides implementation of SAX writer to output XML ||
 || XML.SAX.Readers || Provides interface type of SAX reader ||
 || XML.SAX.Simple_Readers || Provides simple implementation SAX reader. It supports namespaces and partially supports validation ||
+|| [source:trunk/matreshka/source/xml/xml-sax-writers.ads XML.SAX.Writers] || Provides interface type for SAX writers and set of convenience subprograms ||
 
 Other packages are part of the implementation and must not be used by the application.
+
+== SAX Writer Example ==
+
+SAX writer allows to generate XML documents and streams. Below is small example of its use to generate XMPP stream.
+
+{{{
+with Ada.Wide_Wide_Text_IO;
+
+with League.Strings;
+with XML.SAX.Attributes;
+with XML.SAX.Pretty_Writers;
+
+procedure SAX_Writer_Example is
+
+   use League.Strings;
+   
+   function "+" (Item : Wide_Wide_String) return Universal_String
+     renames To_Universal_String;
+   
+   Lang_Attribute      : constant Universal_String := +"xml:lang";
+   Stream_URI          : constant Universal_String
+     := +"http://etherx.jabber.org/streams";
+   Stream_Prefix       : constant Universal_String := +"stream";
+   Stream_Element      : constant Universal_String := +"stream";
+   Features_Element    : constant Universal_String := +"features";
+   Client_URI          : constant Universal_String := +"jabber:client";
+   Id_Attribute        : constant Universal_String := +"id";
+   From_Attribute      : constant Universal_String := +"from";
+   Version_Attribute   : constant Universal_String := +"version";
+   Compression_URI     : constant Universal_String
+     := +"http://jabber.org/features/compress";
+   Compression_Element : constant Universal_String := +"compression";
+   Method_Element      : constant Universal_String := +"method";
+   
+   Writer     : XML.SAX.Pretty_Writers.SAX_Pretty_Writer;
+   Attributes : XML.SAX.Attributes.SAX_Attributes;
+   
+begin
+   Writer.Start_Document;
+   Writer.Start_Prefix_Mapping (Namespace_URI => Client_URI);
+   Writer.Start_Prefix_Mapping 
+     (Namespace_URI => Stream_URI, Prefix => Stream_Prefix);
+
+   --  Open stream element
+   
+   Attributes.Set_Value
+     (Qualified_Name => Id_Attribute, Value => +"656571601");
+   Attributes.Set_Value 
+     (Qualified_Name => From_Attribute, Value => +"jabber.ru");
+   Attributes.Set_Value (Qualified_Name => Version_Attribute, Value => +"1.0");
+   Attributes.Set_Value (Qualified_Name => Lang_Attribute, Value => +"ru");
+   Writer.Start_Element
+     (Namespace_URI => Stream_URI, 
+      Local_Name    => Stream_Element, 
+      Attributes    => Attributes);
+   
+   --  Open features element
+   
+   Writer.Start_Element
+     (Namespace_URI => Stream_URI, Local_Name => Features_Element);
+   
+   --  Open compression element
+   
+   Writer.Start_Prefix_Mapping (Namespace_URI => Compression_URI);
+   Writer.Start_Element
+     (Namespace_URI => Compression_URI, Local_Name => Compression_Element);
+   
+   --  Output method
+
+   Writer.Start_Element
+     (Namespace_URI => Compression_URI, Local_Name => Method_Element);
+   Writer.Characters (+"zlib");
+   Writer.End_Element
+     (Namespace_URI => Compression_URI, Local_Name => Method_Element);
+   
+   --  Close compression element
+   
+   Writer.End_Element
+     (Namespace_URI => Compression_URI, Local_Name => Compression_Element);
+   Writer.End_Prefix_Mapping;
+   
+   --  Close features element
+   
+   Writer.End_Element
+     (Namespace_URI => Stream_URI, Local_Name => Features_Element);
+   
+   --  Close stream element
+   
+   Writer.End_Element
+     (Namespace_URI => Stream_URI, Local_Name => Stream_Element);
+   Writer.End_Prefix_Mapping (Prefix => Stream_Prefix);
+   Writer.End_Prefix_Mapping;
+   Writer.End_Document;
+   
+   Ada.Wide_Wide_Text_IO.Put_Line (Writer.Text.To_Wide_Wide_String);
+end SAX_Writer_Example;
+}}}
+
+This program generates following output (output is formatted to be more readable):
+
+{{{
+<?xml version="1.0"?>
+<stream:stream xmlns="jabber:client" xmlns:stream="http://etherx.jabber.org/streams"
+  id="656571601" from="jabber.ru" version="1.0" xml:lang="ru">
+  <stream:features xmlns="jabber:client">
+    <compression xmlns="http://jabber.org/features/compress">
+      <method>zlib</method>
+    </compression>
+  </stream:features>
+</stream:stream>
+}}}