Output a comment with unknown attributes

[zeichenreihe]

As the jvm must silently ignore any unknown attributes, and having a look at attributes might be relevant, VF showing attributes it doesn't know (in comment form), would be a nice feature to have.

If for example the ClassFile structure has some attribute with name VFDoesntKnowThis, with the data in the info being 20, 30, 40, 155, it should produce something like, possibly even escaping non-printable (or non-ascii) utf8 in the name

// VF: Unknown Attribute: "VFDoesntKnowThis" [20, 30, 40, 255]
// VF: Unknown Attribute: "VFDoesntKnowThisAgain" []
class ThatClass {
  // VF: Unknown Attribute: "VFDoesntKnowThisFieldAttr" [0, 255]
  String foo;

  // VF: Unknown Attribute: "VFDoesntKnowThisMethodAttr" []
  void bar() {
    // VF: Unknown Attribute: "VFDoesntKnowThisCodeAttr" [23, 233]
    System.out.println("Hello world!");
  }
}

Something similar should happen for an attribute on a field_info and on a method_info, and for a Code_attribute, it should be in the first line of the method.

[skyrising]

The JVM must silently ignore them, so why shouldn't VF ignore them as well? Sure it might be interesting to see them, but javap can already do that, so I don't really see much value in VF outputting a list of numbers.