ConstantFieldref fieldRef= (ConstantFieldref) constantPool.getConstant(index, Constants.CONSTANT_Fieldref);
FieldAccess fa= new FieldWrite();
fa.setName(getFieldName(fieldRef));
fa.setType(new ObjectType(fieldRef.getClass(constantPool)));
fa.initialize(methodDecl);
if (opcode == Const.PUTFIELD)
{
fa.setExpression(stack.pop());
}