public class unSafeArrayDemo {

    private static final sun.misc.Unsafe UNSAFE;

    private static final long TBASE;

    private static final int TSHIFT;

    static {

        int ts;

        try {

            UNSAFE = getUnsafe();

            TBASE = UNSAFE.arrayBaseOffset(String[].class);

            ts = UNSAFE.arrayIndexScale(String[].class);

        } catch (Exception e) {

            throw new Error(e);

        }

        TSHIFT = 31 - Integer.numberOfLeadingZeros(ts);

    }

	static Unsafe getUnsafe() throws NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {

    	Field f = Unsafe.class.getDeclaredField("theUnsafe");

    	f.setAccessible(true);

    	Unsafe unsafe = (Unsafe)f.get(null);

		return unsafe;

    }

	@SuppressWarnings("unchecked")

    static final String entryAt(String[] tab, int i) {

        return (String) UNSAFE.getObjectVolatile(tab, ((long)i << TSHIFT) + TBASE);

    }

	public static void main(String[] args) {

		int nLen = 37;

		String[] table = new String[nLen];

		for (int i = 0; i < nLen; i++) {

			table[i] = "数值为:  " + String.valueOf(i + 26);

		}

		String str = entryAt(table, 23);

		System.out.println(str);

	}

}