[Soot-list] ConcurrentModificationException when invoking getMethods()

[Fang Zhou]

Hi all,

I am trying to get all functions' arguments with soot. However, when I
use getMethods() or iterator on the list of methods, I always get such
error message:
"Exception in thread "main" java.util.ConcurrentModificationException
        at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:909)
        at java.util.ArrayList$Itr.next(ArrayList.java:859)
        at soot.SootClass$1.next(SootClass.java:505)
        at soot.SootClass$1.next(SootClass.java:494)"

Why is the list of methods changed during my program since I do not
run any analysis yet?

Below is the code I use:

public class Test {
        public static void main(String[] args) {
                String classPath = args[0];
                configureSoot(classPath);

                Scene.v().loadNecessaryClasses();
                Iterator<SootClass> scIter =
Scene.v().getApplicationClasses().snapshotIterator();
                while (scIter.hasNext()) {
                        SootClass sc = scIter.next();
                        System.out.println("ClassName: " +
sc.getName() + ", Methods: " + sc.getMethodCount());

                        //SootMethod sMethod = sc.getMethods();
                        Iterator<SootMethod> smIter = sc.methodIterator();
                        while (smIter.hasNext()) {
   //Error happens
                                SootMethod sMethod = smIter.next();
           ... ... ...
        }

        private static void configureSoot(String classpath) {
                Options.v().set_whole_program(true);
                Options.v().set_allow_phantom_refs(true);
                Options.v().set_prepend_classpath(true);
                Options.v().set_src_prec(Options.src_prec_class);
                ArrayList<String> list = new ArrayList<>();
                list.add(classpath);
                Options.v().set_process_dir(list);
                Options.v().set_output_dir("/tmp/sootOutput");
        }
}

Thanks,
Fang