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1
2$Id$
3
4"TODO" list for JustIce, the Java Class File Verifier by Enver Haase.
5
6- JustIce uses object generalization during pass 3b,  as  supposed  by
7Sun.  However,  there  are better methods such as the idea proposed by
8Staerk et al.: using sets of object types.  JustIce  may  reject  code
9that is not rejected by traditional JVM-internal  verifiers  for  this
10reason. The corresponding checks all have  some  "TODO"  tag  with  an
11explanation; they're all in the 'InstConstraintVisitor.java' file.
12Users  encountering  problems  should  simply  comment  them  out  (or
13uncomment them) as they like. The default is some setting  that  works
14well when using
15$ java org.apache.bcel.verifier.TransitiveHull java.lang.String
16meaning there are no rejects caused by the above problem in a  lot  of
17usual classes.
18
19- There are a few bugs concerning access rights of referenced  methods
20and  probably  fields.  The  tests  for access rights that Sun defines
21should happen in pass four (which JustIce performs during pass 3a) are
22unintentionally  omitted.  This also happened to Sun and IBM with some
23of their version 1.3 JVMs. Thanks Markus Dahm.
24
25- There are bugs because of an ambiguity in the Java  Virtual  Machine
26Specification,  Second  Edition.  These have to do with inheritance: A
27method invocation like MyObject::equals(Object) is considered illegal,
28if  MyObject  has  no  overriding  definition  of  equals(Object). Sun
29clarified this issue via electronic mail:  the  invocation  is  legal,
30because  MyObject  inherits  the  member  function equals(Object) from
31Object::equals(Object). The search algorithms don't seem to be trivial
32because  interfaces  can  not  only  specify methods, but also declare
33fields. Also, access modifiers have to be honoured (see above).
34
35- It is not verified if classes that propose they would  implement  an
36interface _really_ implement all the methods.
37
38- It is not verified that interfaces are actually  tagged  'abstract'.
39
40- The InstructionContext.getSuccessors() method may return the same
41successor more than one time. For performance reasons the ControlFlow-
42Graph.InstructionContextImpl class should return an array where the
43successors are pairwise disjoint. It should also be cached so that we
44don't have to do this calculation every time.
45
46***End of File***
47