原文地址：

为了便以理解，此处引用原文：

Assuming no SecurityManager is preventing you from doing this, you can use setAccessible to get around private and resetting the modifier to get rid of final, and actually modify a private static final field.

Here's an example:

import java.lang.reflect.*;public class EverythingIsTrue {   static void setFinalStatic(Field field, Object newValue) throws Exception {      field.setAccessible(true);      Field modifiersField = Field.class.getDeclaredField("modifiers");      modifiersField.setAccessible(true);      modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);      field.set(null, newValue);   }   public static void main(String args[]) throws Exception {            setFinalStatic(Boolean.class.getField("FALSE"), true);      System.out.format("Everything is %s", false); // "Everything is true"   }}

Assuming no SecurityException is thrown, the above code prints "Everything is true".

What's actually done here is as follows:

• The primitive boolean values true and false in main are autoboxed to reference type Boolean "constants" Boolean.TRUE and Boolean.FALSE
• Reflection is used to change the  to refer to the Booleanreferred to by Boolean.TRUE
• As a result, subsequently whenever a false is autoboxed to Boolean.FALSE, it refers to the same Boolean as the one refered to by Boolean.TRUE
• Everything that was "false" now is "true"