mandatory child in java_grammar but doesn't exist in ASTs

in java_grammar, I found some AST Nodes which have mandatory children but these children don't exist in ASTs.

For example,

1. MethodDeclaration has following mandatory children which don't exist in ASTs: typeParameters, parameters, extraDimensions2, thrownExceptionTypes

2. PackageDeclaration has 1 mandatory child, annotations, which doesn't exist in ASTs.

3. TypeDeclaration has two mandatory children: typeParameters, superInterfaceTypes