[Soot-list] Soot changes method signature after de-compilation from jimple to java

[Souvik Pal]

Hi,
First of all sorry for this late reply.


On Tue, Apr 29, 2014 at 6:46 PM, Marc-André Laverdière <
marc-andre.laverdiere-papineau at polymtl.ca> wrote:

> Hi Souvik,
>
> First, Soot 2.3 is really really old. Have you given thought to
> upgrading to 2.5? Or even better, the cutting-edge development branch?
>

Will definitely try to upgrade to latest version of soot. I hope that the
transition would be smooth.


> Second, I don't understand what you are asking for... what do you mean
> by 'original signature of the API'?
>

Let me explain the problem in detail.

I have a Java application that uses Hibernate <http://hibernate.org/>(a
popular ORM for Java) for persisting objects in database. In Hibernate, on
of the most popular ways to retrieve an object from database (into memory)
is by using the API
session.get<http://docs.jboss.org/hibernate/orm/3.5/javadocs/org/hibernate/Session.html>.
It takes the class of the user defined object and the primary key or
essentially the unique id of that object as parameters. So the signature of
this API is

*java.lang.Object get(java.lang.Class, java.io.Serializable)*

Now, my task is to analyse such java application which uses Hibernate APIs
and suggest possible optimization. Optimizations can be as simple as live
variable analysis or constant propagation. I need to reproduce the java
application with transformation embedded, i.e. with a few 'dead-codes'
deleted or some lines of the code modified capturing the effect of constant
propagation.

For this I am using SOOT. I am using Jimple as intermediate representation,
analysing the code, adding suitable transformation and then decompiling the
Jimple into Java. This is where the problem arises. While converting the
Java to Jimple, the java statement containing the Hibernate API session.get
changes as follows into Jimple statement.

Java Statement:  *User user1 = (User) session.get(User.class, 1);* //
assume 1 as an the id of the User object to be retrieved

Jimple Statement(s):
*$r1 = staticinvoke <java.lang.Integer: java.lang.Integer valueOf(int)>(1)*

// User class is located in package *testProject.hibernate.examples*
 *$r2 = interfaceinvoke session.<org.hibernate.Session:
java.lang.Object get(java.lang.Class,java.io <http://java.io>.Serializable)
> (class **"testProject/hibernate/examples/User", $r1)*

In the decompiled program (using dava), the same Java statement appears as:

*User user1 = (User)
session.get(class "testProject/hibernate/examples/User",
Integer.valueOf(1))*

So the first argument of the API changed from *User.class* to *class *
*"testProject/hibernate/examples/User"*
Hibernate can not recognize this, and the re-written (optimize) java
program fails to compile.

I am interested to know how can I get rid of this issue. Will upgrading to
latest SOOT version solve this issue?

Thanks and regards.




> Marc-André Laverdière-Papineau
> Doctorant - PhD Candidate
>
> On 04/29/2014 06:43 AM, Souvik Pal wrote:
> > Hi all,
> >
> > I am new to soot. I am using soot (soot 2.3) to analyze simple Hibernate
> > programs.
> >
> > Hibernate *session.get* API requires a *java.lang.Class* and
> > *java.io.Serializable* type arguments. However when I am de-compiling
> > the Jimple expressions into java, the API signature changes and
> > Hibernate can not recognize it.
> >
> > Example.
> >
> > *User aUser = (User) session.get(User.class, 1);*
> > get transformed to in the de-compiled program.
> > *aUser = (User) session.get(class
> > "path/to/class/User", Integer.valueOf(1));*
> >
> > The intermediate Jimple statements are
> >
> > *$r1 = staticinvoke <java.lang.Integer: java.lang.Integer
> valueOf(int)>(1)
> > *
> > *$r2 = interfaceinvoke session.<org.hibernate.Session: java.lang.Object
> > get(java.lang.Class,java.io.Serializable)>(class
> > "**path/to/class/User**", $r1)*
> >
> >
> > Please let me know what should I do to keep the original signature of
> > the API.
> >
> > Thanks and regards,
> >
> > --
> > *Souvik Pal*
> >
> >
> > _______________________________________________
> > Soot-list mailing list
> > Soot-list at CS.McGill.CA
> > https://mailman.CS.McGill.CA/mailman/listinfo/soot-list
> >
> _______________________________________________
> Soot-list mailing list
> Soot-list at CS.McGill.CA
> https://mailman.CS.McGill.CA/mailman/listinfo/soot-list
>



-- 
*Souvik Pal*
Student M. Tech.,
CSE, IIT Bombay
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.CS.McGill.CA/pipermail/soot-list/attachments/20140430/4b904c11/attachment.html