Accessing and Modifying Private and Final variables in java

In the office, today, i got into a situation where i have to access private members of a java class without setters and getters. Initially i thought its impossible!! As usual searched in google. Below is the epitome of my findings. In fact, we can access not only private variables but also modify them. One more interesting fact is that we can modify final variables. We can achieve this through Reflection. Only Exception to this is we cannot access or modify static final variables. Below example explains everything. Class PersonalDetails contains a static private, a final private and a private variable. import java.lang.reflect.*; class PersonalDetails { private static String fname = "Ravi"; private final String lname="Sankar"; private int id = 123456; } public class ReflectionAbuse { public static void main(String[] args) throws Exception { PersonalDetails personalDetails = new PersonalDetails(); Field fnameField = PersonalDetails.class.getDeclaredField("fname"); Field lnameField = PersonalDetails.class.getDeclaredField("lname"); Field idField = PersonalDetails.class.getDeclaredField("id"); /** Setting Accessible to true to access the variables */ fnameField.setAccessible(true); lnameField.setAccessible(true); idField.setAccessible(true); /** Accessing private and Fianl Variables */ String fname = (String)fnameField.get(personalDetails); String lname = (String)lnameField.get(personalDetails); int id = idField.getInt(personalDetails); /** Before Setting: Printing the values */ System.out.println("fname="+fname+" | lname="+lname+" | id="+id); /** Modifing Private and Final Variables */ fnameField.set(personalDetails, "Anil"); lnameField.set(personalDetails,"Kumara"); idField.set(personalDetails,987654); fname = (String)fnameField.get(personalDetails); lname = (String)lnameField.get(personalDetails); id = idField.getInt(personalDetails); /** After Setting: Printing the values */ System.out.println("fname="+fname+" | lname="+lname+" | id="+id); } } Output:- fname=Ravi | lname=Sankar | id=123456 fname=Anil | lname=Kumara | id=987654 If we try to modify value of a static final then it will throw java.lang.IllegalAccessException: exception References:- http://www.roseindia.net/javatutorials/jdk5_final_is_not_final.shtml http://www.javalobby.org/java/forums/m91815224.html