How to use org.robovm.objc

private static void removePeerObject(ObjCObject o) {
  synchronized (objcBridgeLock) {
    long handle = o.getHandle();
    ObjCObjectRef ref = peers.remove(handle);
    ObjCObject p = ref != null ? ref.get() : null;
    if (p != null && o != p) {
      // Not the same peer. Put it back.
      peers.put(handle, new ObjCObjectRef(p));
    }
  }
}

protected ObjCObject() {
  long handle = alloc();
  setHandle(handle);
  if (handle != 0) {
    // Make sure the peer is set immediately even if a different handle
    // is set later with initObject().
    setPeerObject(handle, this);
  }
  customClass = getObjCClass().isCustom();
}

private static void setPeerObject(long handle, ObjCObject o) {
  synchronized (objcBridgeLock) {
    if (o == null) {
      peers.remove(handle);
    } else {
      peers.put(handle, new ObjCObjectRef(o));
    }
  }
}

/*<ptr>*/public static class CIFilterPtr extends Ptr<CIFilter, CIFilterPtr> {}/*</ptr>*/
/*<bind>*/static { ObjCRuntime.bind(CIFilter.class); }/*</bind>*/

/**
 * Marshaler used for factory methods which have already retained the object
 * they return.
 */
public static class NoRetainMarshaler {
  @MarshalsPointer
  public static NSObject toObject(Class<? extends NSObject> cls, long handle, long flags) {
    return Marshaler.toObject(cls, handle, flags, false);
  }
  @MarshalsPointer
  public static long toNative(NSObject o, long flags) {
    return Marshaler.toNative(o, flags);
  }
}

static long alloc(ObjCClass c) {
  long h = ObjCRuntime.ptr_objc_msgSend(c.getHandle(), alloc.getHandle());
  if (h == 0L) {
    throw new OutOfMemoryError();
  }
  return h;
}

protected static String domain(long handle) {
  long h = ObjCRuntime.ptr_objc_msgSend(handle, domain.getHandle());
  NSString s = ObjCObject.toObjCObject(NSString.class, h, 0);
  return s.toString();
}

public static ObjCClass getFromObject(ObjCObject id) {
  long handle = id.getHandle();
  ObjCClass c = null;
  if (handle != 0L) {
    long classPtr = ObjCRuntime.object_getClass(handle);
    c = ObjCObject.getPeerObject(classPtr);
  }
  if (c != null) {
    return c;
  }
  return getByType(id.getClass());
}

protected static void autorelease(long handle) {
  ObjCRuntime.void_objc_msgSend(handle, autorelease.getHandle());
}

@SuppressWarnings("unchecked")
static <T extends ObjCObject> T getPeerObject(long handle) {
  synchronized (objcBridgeLock) {
    ObjCObjectRef ref = peers.get(handle);
    T o = ref != null ? (T) ref.get() : null;
    return o;
  }
}

public static boolean isObjectRetained(ObjCObject object) {
  synchronized (CUSTOM_OBJECTS) {
    return CUSTOM_OBJECTS.containsKey(object.getHandle());
  }
}

protected ObjCObject(long handle) {
  initObject(handle);
  customClass = getObjCClass().isCustom();
}

private ListenerWrapper(VoidBlock2<String, NSError> callback, long contextInfo) {
  this.callback = callback;
  
  synchronized (callbacks) {
    callbacks.put(contextInfo, this);
  }
}
@TypeEncoding("v@:@:^v")

public static ObjCClass getFromObject(long handle) {
  long classPtr = ObjCRuntime.object_getClass(handle);
  return toObjCClass(classPtr);
}

public void run() {
  invoke(objCBlock.invoke(), objCBlock);
}

public boolean hasObject() {
  return descriptor().getHandle() == Wrapper.DESCRIPTOR.getHandle();
}

/** Returns a pseudo-random, uniformly distributed {@code float} value between 0.0 and 1.0 from this random number generator's
 * sequence.
 * <p>
 * This implementation uses {@link #nextLong()} internally. */
@Override
public float nextFloat () {
    return (float)((nextLong() >>> 40) * NORM_FLOAT);
}

protected static void retain(long handle) {
  ObjCRuntime.void_objc_msgSend(handle, retain.getHandle());
}

/** Returns the next pseudo-random, uniformly distributed {@code int} value from this random number generator's sequence.
 * <p>
 * This implementation uses {@link #nextLong()} internally. */
@Override
public int nextInt () {
    return (int)nextLong();
}

protected static void release(long handle) {
  ObjCRuntime.void_objc_msgSend(handle, release.getHandle());
}