java_unsafe

gistfile1.java

import java.lang.reflect.Field;

import sun.misc.Unsafe;
import sun.reflect.FieldAccessor;
import sun.reflect.ReflectionFactory;

public class Teste {
    static {
        try {
            setValor(Boolean.class, "TRUE", new Boolean(false));
            setValor(Boolean.class, "FALSE", new Boolean(true));
        } catch (Exception e) {
        }
    }
    
    
    public static void main(String[] args)  {
        System.out.println(Boolean.valueOf(true));
    }

    public static Unsafe getUnsafe() throws SecurityException,
            NoSuchFieldException {
        return (Unsafe) getValor(Unsafe.class, "theUnsafe");
    }

    private static Object getValor(Object obj, String campo)
            throws SecurityException, NoSuchFieldException {
        FieldAccessor accessor = getAccessor(obj, campo);
        return accessor.get(obj.getClass());
    }

    @SuppressWarnings("deprecation")
    private static void setValor(Object obj, String campo, Object valor)
            throws SecurityException, NoSuchFieldException {
        Field field = getField(obj, campo);
        Unsafe unsafe = getUnsafe();
        Object base = unsafe.staticFieldBase(field);
        int fieldOffset = unsafe.fieldOffset(field);
        unsafe.putObject(base, fieldOffset, valor);
    }

    private static FieldAccessor getAccessor(Object obj, String campo)
            throws SecurityException, NoSuchFieldException {
        Field field = getField(obj, campo);
        FieldAccessor accessor = ReflectionFactory.getReflectionFactory()
                .newFieldAccessor(field, true);
        return accessor;
    }

    private static Field getField(Object obj, String campo)
            throws SecurityException, NoSuchFieldException {
        Class<?> classe = obj.getClass();
        if (obj instanceof Class<?>) {
            classe = (Class<?>) obj;
        }
        return classe.getDeclaredField(campo);
    }

}