Finding all classes available in an android application.

Reflection methods in Android

//To list all methods in android application

public void listAllClasses() {

        try {
            DexFile df = new DexFile(getPackageCodePath());
            for (Enumeration<String> iter = df.entries(); iter.hasMoreElements();) {
                String classPath = iter.nextElement();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
}

//To get generic types defined in a an object initilization
/*
        //Assume we have some object definition like this: 
        CallbackListener callbacklistener = new CallbackListener<SomeController.Response>();
        
        //We have to do this in order to get type of generic type defined in 
        Class responseType = (Class<? extends Response>) ((ParameterizedType) callbackListener.getClass().getGenericSuperclass())
                .getActualTypeArguments()[0];

*/


//To find all classes of a specific type

public static Set<Class> getClassesOfType(@NonNull Class typeOfClass, @NonNull String inPackageName, @NonNull Context context, boolean onlyIncludeSubclasses) {

        Set<Class> classes = new HashSet<>();

        try {
            DexFile df = new DexFile(context.getPackageCodePath());
            for (Enumeration<String> iter = df.entries(); iter.hasMoreElements();) {
                String classPath = iter.nextElement();

                if(classPath.startsWith(inPackageName)) {

                    Class main = Class.forName(classPath);
                    Class c = main;

                    do {

                        if(c.getName().equals(typeOfClass.getName())) {

                            if(onlyIncludeSubclasses && c == main)
                                break;

                            classes.add(main);
                            break;
                        }

                        c = c.getSuperclass();

                    } while ( c != null);

                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return classes;
    }