Change the way disctionary values are set in lookups when combined with ContainsKey

Author: milkshakeuk

CHANGELOG.md

@@ -8,7 +8,15 @@ All notable changes to this project will be documented in this file.
 ## Previous Releases
 ###
 
-## [3.0.3] - 2021-08-09
+## [3.0.4] - 2021-08-11
+This change is to prevent the following Exception:
+
+> System.ArgumentException - An item with the same key has already been added.
+
+In cases where dictionaries / hashtables are used for lookups such as `Escape.cs` when there multiple threads trying to add to them at the same time.
+
+Instead of using `Add(key, value)` which only allows 1 items with a given key to be added to the dictionary / hashtable, we are using the index accessor to set or update the value in a last one wins scenario, but only when its combined with `ContainsKey` which has indicated that an item with that key shouldn't exist.
+## [3.0.3] - 2021-08-10
 This change updates the `PipeParser` Version check when obtaining encoding characters from a message object in order to encode it to HL7; `string.CompareOrdinal` is now used instead of `System.Version` which is more forgiving when a version contains non numerical characters.
 
 ## [3.0.2] - 2021-08-09

build/nHapi.v3.nuspec

@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2013/05/nuspec.xsd">
     <metadata>
         <id>nhapi</id>
-        <version>3.0.3</version>
+        <version>3.0.4</version>
         <authors>Chad Chenoweth,Duane Edwards,Jake Aitchison</authors>
         <license type="expression">MPL-2.0</license>
         <projectUrl>https://github.com/nHapiNET/nHapi</projectUrl>
@@ -13,7 +13,7 @@
 NHapi allows Microsoft .NET developers to easily use an HL7 2.x object model. This object model allows for parsing and encoding HL7 2.x data to/from Pipe Delimited or XML formats. A very handy program for use in the health care industry.
 
 This project is NOT affiliated with the HL7 organization. This software just conforms to the HL7 2.x specifications.</description>
-        <releaseNotes>https://github.com/nHapiNET/nHapi/releases/tag/v3.0.3</releaseNotes>
+        <releaseNotes>https://github.com/nHapiNET/nHapi/releases/tag/v3.0.4</releaseNotes>
         <tags>HL7 parsing healthcare HAPI xml</tags>
         <readme>docs\README.md</readme>
         <dependencies>

src/NHapi.Base/Model/GenericMessage.cs

@@ -72,7 +72,7 @@ public static Type GetGenericMessageClass(string version)
 
                 if (c != null)
                 {
-                    GenericMessages.Add(version, c);
+                    GenericMessages[version] = c;
                 }
             }
 

src/NHapi.Base/NHapi.Base.csproj

@@ -4,15 +4,15 @@
     <TargetFrameworks>net35;netstandard2.0</TargetFrameworks>
     <DocumentationFile>bin\$(Configuration)\$(TargetFramework)\$(AssemblyName).xml</DocumentationFile>
     <PackageId>nhapi.base</PackageId>
-    <PackageVersion>3.0.3</PackageVersion>
+    <PackageVersion>3.0.4</PackageVersion>
     <Authors>Chad Chenoweth;Duane Edwards;Jake Aitchison</Authors>
     <PackageLicenseExpression>MIT</PackageLicenseExpression>
     <PackageProjectUrl>https://github.com/nHapiNET/nHapi</PackageProjectUrl>
     <RepositoryUrl>https://github.com/nHapiNET/nHapi.git</RepositoryUrl>
     <RepositoryType>git</RepositoryType>
     <Description>The core components for parsing/encoding HL7 messages. Contains the base classes and interfaces for datatypes, segments, and messages.</Description>
     <PackageTags>HL7;parsing;healthcare;HAPI;xml</PackageTags>
-    <PackageReleaseNotes>https://github.com/nHapiNET/nHapi/releases/tag/v3.0.3</PackageReleaseNotes>
+    <PackageReleaseNotes>https://github.com/nHapiNET/nHapi/releases/tag/v3.0.4</PackageReleaseNotes>
     <PackageReadmeFile>docs\README.md</PackageReadmeFile>
     <AssemblyOriginatorKeyFile>..\..\NHapi.snk</AssemblyOriginatorKeyFile>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>

src/NHapi.Base/Parser/Escape.cs

@@ -252,7 +252,7 @@ private static EncodingLookups BuildEncodingLookups(EncodingCharacters encChars)
             if (!VariousEncChars.ContainsKey(encChars))
             {
                 // this means we haven't got the sequences for these encoding characters yet - let's make them
-                VariousEncChars.Add(encChars, new EncodingLookups(encChars));
+                VariousEncChars[encChars] = new EncodingLookups(encChars);
             }
 
             return VariousEncChars[encChars];
@@ -323,7 +323,7 @@ private void TryAddEscapeSequence(char key, string value)
             {
                 if (!EscapeSequences.ContainsKey(key))
                 {
-                    EscapeSequences.Add(key, value);
+                    EscapeSequences[key] = value;
                 }
             }
         }

src/NHapi.Base/Parser/PipeParser.cs

@@ -921,7 +921,7 @@ private IStructureDefinition GetStructureDefinition(IMessage theMessage)
                 { theMessage.GetStructureName(), retVal },
             };
 
-            structureDefinitions.Add(messageType, dictionary);
+            structureDefinitions[messageType] = dictionary;
 
             return retVal;
         }

src/NHapi.Base/SupportClass.cs

@@ -1485,7 +1485,7 @@ private void DoParsing()
                                             stackNameSpace.Push(name);
                                             Stack namespaceStack = new Stack();
                                             namespaceStack.Push(prefixName);
-                                            prefixes.Add(namespaceURI, namespaceStack);
+                                            prefixes[namespaceURI] = namespaceStack;
                                             if (callBackHandler != null)
                                             {
                                                 ((IXmlSaxContentHandler)callBackHandler).startPrefixMapping(prefixName, namespaceTemp);