code: @Override
      public void sawOpcode(int seen) {
          if ((seen == Const.GETFIELD) || (seen == Const.PUTFIELD)) {
              String fieldName = getNameConstantOperand();
              FieldInfo fi = localizableFields.get(fieldName);
              if (fi != null) {
                  SourceLineAnnotation sla = SourceLineAnnotation.fromVisitedInstruction(this);
                  fi.setSrcLineAnnotation(sla);
              }
          }
      }
docs: implements the visitor to add SourceLineAnnotations for fields in constructors and static initializers.
  
  @param seen
  the opcode of the currently visited instruction