nitsanw

    public static final Unsafe unsafe;
    static
    {
        try
        {
            // This is a bit of voodoo to force the unsafe object into
            // visibility and acquire it.
            // This is not playing nice, but as an established back door it is
            // not likely to be taken away.
            Field field = Unsafe.class.getDeclaredField("theUnsafe");

nitsanw

    private static final long valueFieldOffset;
    private static final long countFieldOffset;
    private static final long offsetFieldOffset;

    static
    {
        try
        {
            valueFieldOffset = UnsafeAccess.unsafe.objectFieldOffset(String.class.getDeclaredField("value"));
            countFieldOffset = UnsafeAccess.unsafe.objectFieldOffset(String.class.getDeclaredField("count"));

nitsanw

    public final static String buildUnsafe(char[] chars){
        String mutable = new String();// an empty string to hack
        UnsafeAccess.unsafe.putObject(mutable,valueFieldOffset,chars);
        UnsafeAccess.unsafe.putInt(mutable,countFieldOffset,chars.length);
        return mutable;
    }
    public final static String buildUnsafe(char[] chars, int offset, int length){
        String mutable = new String();// an empty string to hack
        UnsafeAccess.unsafe.putObject(mutable,valueFieldOffset,chars);
        UnsafeAccess.unsafe.putInt(mutable,countFieldOffset,length);

nitsanw

...
            // On the ping thread
            for (long l = 0; l < iterations; l++) {
		pingValue.set(l);
		while (pongValue.get() != l)
		    ;
	    }

...
            // On the pong thread

nitsanw

private volatile long value;
private static final long valueOffset;

static {
  try {
    valueOffset = UnsafeAccess.unsafe.objectFieldOffset(VolatileLong.class.getDeclaredField("value"));
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

nitsanw

final class Producer implements Runnable {
  public void run() {
    latch.countDown();
    for (long l = 0; l < ITERATIONS; l++) {
      values[(int) l] = l;
      producerIndex.set(l);
    }
  }
}

nitsanw

// Server loop
...
    accepted = serverSocket.accept();
    accepted.socket().setTcpNoDelay(true);
    accepted.configureBlocking(false);
    serverSocket.close();
    while (!Thread.interrupted()) {
        buffy.clear();
        do {
            if (accepted.read(buffy) == -1)

nitsanw

private static final long addressOffset;
static {
	try {
		addressOffset = UnsafeAccess.unsafe.objectFieldOffset(Buffer.class.getDeclaredField("address"));
	} catch (Exception e) {
		throw new RuntimeException(e);
	}
}

public static long getAddress(ByteBuffer buffy) {

nitsanw

package alignment;

import java.nio.ByteBuffer;

import util.UnsafeAccess;
import static util.UnsafeDirectByteBuffer.*;

import com.google.caliper.Param;
import com.google.caliper.SimpleBenchmark;

nitsanw

<project xmlns:ivy="antlib:org.apache.ivy.ant" name="TheBestestProjectEver" default="build">
  	<property name="ivy.install.version" value="2.0.0-beta1" />
	<property name="ivy.jar.dir" value="${basedir}/ivy" />
	<property name="ivy.jar.file" value="${ivy.jar.dir}/ivy.jar" />
	<property name="allocation.jar.file" value="${basedir}/lib/allocation.jar" />
	<condition property="skip.download.ivy">
		<and>
			<available file="${ivy.jar.file}"/>
		</and>
	</condition>