gistfile1.java

package io.netty.buffer;

import sun.misc.Unsafe;

import java.lang.reflect.Field;
import java.nio.Buffer;
import java.nio.ByteBuffer;

/**
 *
 */
public class Test2 {

    public static void main(String[] args) throws Exception {

        Unsafe unsafe = getUnsafe();

        int capacity = 1000;

        ByteBuffer buff = ByteBuffer.allocateDirect( capacity );

        Field addressField = Buffer.class.getDeclaredField("address");
        addressField.setAccessible(true);

        long memoryAddress = addressField.getLong( buff );

        System.out.printf( "Working with memory address: %s\n", memoryAddress );

        long addr = memoryAddress;

        unsafe.putOrderedInt( buff, addr, 666 );

    }

    public static Unsafe getUnsafe() throws Exception {
        Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");
        unsafeField.setAccessible(true);
        return (Unsafe) unsafeField.get(null);
    }

    public static long getAddress( ByteBuffer buff ) throws Exception {
        Field addressField = Buffer.class.getDeclaredField("address");
        addressField.setAccessible(true);

        return addressField.getLong( buff );

    }

}