CallGraph with no main

package doAnalysis;

import java.util.*;

import soot.*;
import soot.jimple.toolkits.callgraph.*;
import soot.options.Options;

public class MyCallGraph {
        static String[] allClasses = { "doAnalysis.FieldAccessible","java.lang.reflect.Fields" };
        static List<String> libDir = Arrays.asList("/home/jalilos/Documents/lib.jar");


        public static ArrayList<SootMethod> getAllMethods() {
                ArrayList<SootMethod> entrypoints = new ArrayList<SootMethod>();
                for (String klass : allClasses) {
                        // klass such as org.abc.MyClass

                        Scene.v().forceResolve(klass, SootClass.SIGNATURES);
                        SootClass soot_class = Scene.v().getSootClass(klass);

                        // adding all non-abstract method as entrypoint
                        for (SootMethod m : soot_class.getMethods()) {
                                if (!m.isAbstract()) {
                                        entrypoints.add(m);
                                }
                        }
                }
                return entrypoints;
        }
        public static SootMethod getMethod(SootClass soot_class, String subsig) {
                SootClass base_class = soot_class;
                while (true) {
                        if (soot_class.declaresMethod(subsig)) {
                                return soot_class.getMethod(subsig);
                        }
                        if (soot_class.hasSuperclass()) {
                                soot_class = soot_class.getSuperclass();
                        }
                        else {
                                System.out.println("cannot find method: " + subsig + " in "
                                                + base_class.getName());
                                System.exit(0);
                        }
                }
        }

        public static void main(String[] args) {
                //System.out.println(libDir); //C:\Users\Jalil0s\Desktop\eclipse\JALILOS\SOOT\lib
                Options.v().set_whole_program(true);
                //Options.v().set_process_dir(libDir); //library dir
                Options.v().set_soot_classpath("../rt.jar:"+libDir+":../jce.jar:.");
                // library dir along with rt.jar/jce.jar from JRE/JDK

                Scene.v().setEntryPoints(getAllMethods());
                Scene.v().loadNecessaryClasses();
                PackManager.v().getPack("wjtp").apply();

                PackManager.v().getPack("wjtp")
                                .add(new Transform("wjtp.myTrans", new SceneTransformer() {

                                        @Override
                                        protected void internalTransform(String phaseName,
                                                        Map options) {
                                                CHATransformer.v().transform();
                                        }
                                }));

                SootClass soot_class = Scene.v().getSootClass("java.lang.reflect.Field");
                SootMethod tgt = getMethod(soot_class, "void setAccessible(boolean)");
                CallGraph cg = Scene.v().getCallGraph();

                @SuppressWarnings("unchecked")
                Iterator<MethodOrMethodContext> source = new Sources(cg.edgesInto(tgt));
                while (source.hasNext()) {
                        SootMethod src = (SootMethod) source.next();
                        // System.out.println(tgt + " may call " + src);
                        System.out.println(src);
                }

        }
}