private void registerFieldUsage(int opcode, String owner, String fName, String desc) {
          final int fieldName = myContext.get(fName);
          final int fieldOwner = myContext.get(owner);
          final int descr = myContext.get(desc);
          if (opcode == Opcodes.PUTFIELD || opcode == Opcodes.PUTSTATIC) {
            myUsages.add(UsageRepr.createFieldAssignUsage(myContext, fieldName, fieldOwner, descr));
          }
          if (opcode == Opcodes.GETFIELD || opcode == Opcodes.GETSTATIC) {
            addClassUsage(TypeRepr.getType(myContext, descr));
          }
          myUsages.add(UsageRepr.createFieldUsage(myContext, fieldName, fieldOwner, descr));
        }
private void registerFieldUsage(int opcode, String owner, String fName, String desc)