put group order information into class annotation

Author: yaitskov

main/java/uk/co/real_logic/sbe/codec/java/GroupOrder.java

@@ -0,0 +1,16 @@
+package uk.co.real_logic.sbe.codec.java;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Daneel Yaitskov
+ */
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ElementType.TYPE})
+public @interface GroupOrder
+{
+ Class[] value();
+}

main/java/uk/co/real_logic/sbe/generation/java/JavaGenerator.java

@@ -99,18 +99,20 @@ public void generate() throws IOException
  try (final Writer out = outputManager.createOutput(className))
  {
  out.append(generateFileHeader(ir.applicableNamespace()));
- out.append(generateClassDeclaration(className));
- out.append(generateMessageFlyweightCode(className, msgToken));
-
  final List<Token> messageBody = tokens.subList(1, tokens.size() - 1);
  int offset = 0;
 
  final List<Token> rootFields = new ArrayList<>();
  offset = collectRootFields(messageBody, offset, rootFields);
- out.append(generateFields(className, rootFields, BASE_INDENT));
-
  final List<Token> groups = new ArrayList<>();
  offset = collectGroups(messageBody, offset, groups);
+
+ generateAnnotations(className, groups, out);
+ out.append(generateClassDeclaration(className));
+ out.append(generateMessageFlyweightCode(className, msgToken));
+
+ out.append(generateFields(className, rootFields, BASE_INDENT));
+
  final StringBuilder sb = new StringBuilder();
  generateGroups(sb, className, groups, 0, BASE_INDENT);
  out.append(sb);
@@ -662,6 +664,37 @@ private CharSequence generateEnumFileHeader(final String packageName)
  );
  }
 
+ private void generateAnnotations(String className, final List<Token> tokens, Writer out) throws IOException
+ {
+ int index = 0;
+ final List<String> groupClassNames = new ArrayList<>();
+ for (int size = tokens.size(); index < size; index++)
+ {
+ if (tokens.get(index).signal() == Signal.BEGIN_GROUP)
+ {
+ final Token groupToken = tokens.get(index);
+ final String groupName = groupToken.name();
+ groupClassNames.add(formatClassName(groupName));
+ }
+ }
+ if (groupClassNames.isEmpty())
+ {
+ return;
+ }
+ out.append("@GroupOrder({");
+ index = 0;
+ for (String name : groupClassNames)
+ {
+ out.append(className).append('.').append(name).append(".class");
+ if (++index < groupClassNames.size())
+ {
+ out.append(", ");
+ }
+ }
+
+ out.append("})\n");
+ }
+
  private CharSequence generateClassDeclaration(final String className)
  {
  return String.format(