[C++]: Enhance intermediate representation to allow for C++ nested namespaces

Author: didenko

sbe-tool/src/main/java/uk/co/real_logic/sbe/ir/Ir.java

@@ -18,6 +18,7 @@
 import org.agrona.Verify;
 
 import java.util.*;
+import java.util.regex.Pattern;
 
 /**
  * Intermediate representation of SBE messages to be used for the generation of encoders and decoders
@@ -35,6 +36,8 @@ public class Ir
     private final Map<Long, List<Token>> messagesByIdMap = new HashMap<>();
     private final Map<String, List<Token>> typesByNameMap = new HashMap<>();
 
+    private final String[] namespaces;
+
     /**
      * Create a new IR container taking a defensive copy of the headerStructure {@link Token}s passed.
      *
@@ -62,6 +65,8 @@ public Ir(
         this.version = version;
         this.semanticVersion = semanticVersion;
         this.headerStructure = new HeaderStructure(new ArrayList<>(headerTokens));
+
+        this.namespaces = Pattern.compile("\\.").split(namespaceName == null ? packageName : namespaceName);
     }
 
     /**
@@ -153,6 +158,16 @@ public String namespaceName()
         return namespaceName;
     }
 
+    /**
+     * Get the namespaces array to be used for generated code.
+     *
+     * @return the namespaces array to be used for generated code.
+     */
+    public String[] namespaces()
+    {
+        return namespaces;
+    }
+
     /**
      * Get the id number of the schema.
      *