Java Unit Test Helpers

HelperMethods.java

import java.lang.reflect.*;

public class HelperMethods {
    @SuppressWarnings("unchecked")
    public static <R, T> R invokePrivateMethod(T object, String methodName, Object... args) {
        final Method methods[] = object.getClass().getDeclaredMethods();
        for (Method method : methods) {
            if (methodName.equals(method.getName())) {
                try {
                    method.setAccessible(true);
                    return (R) method.invoke(object, args);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
        return null;
    }

    @SuppressWarnings("unchecked")
    public static <R, T> R extractPrivateField(T object, String fieldName) {
        final Field fields[] = object.getClass().getDeclaredFields();
        for (Field field : fields) {
            if (fieldName.equals(field.getName())) {
                try {
                    field.setAccessible(true);
                    return (R) field.get(object);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
        return null;
    }

    public static <T, S> void setPrivateField(T object, String fieldName, S setTo) {
        final Field fields[] = object.getClass().getDeclaredFields();
        for (Field field : fields) {
            if (fieldName.equals(field.getName())) {
                try {
                    field.setAccessible(true);
                    field.set(object, setTo);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

}