raycast

final List<Entity> nearby = player.getNearbyEntities(6, 6, 6);

Location pointA = player.getEyeLocation();
Location pointB = player.getEyeLocation().add(player.getEyeLocation().getDirection().normalize().multiply(5));
int numberOfPointsBetweenAAndB = 25;

World tempWorld = pointA.getWorld();
int timeIterated = 0;
double xIncrement = 0.0D;
double yIncrement = 0.0D;
double zIncrement = 0.0D;
double currentX = 0.0D;
double currentY = 0.0D;
double currentZ = 0.0D;

VisibleCheck:
for (int i = 0; i < numberOfPointsBetweenAAndB; i++) {
    if (timeIterated > numberOfPointsBetweenAAndB) {
        break VisibleCheck;
    }
    Location thisLoc;
    if (timeIterated == 0) {
        currentX = pointA.getX();
        currentY = pointA.getY();
        currentZ = pointA.getZ();
        xIncrement = (currentX - pointB.getX()) / numberOfPointsBetweenAAndB;
        yIncrement = (currentY - pointB.getY()) / numberOfPointsBetweenAAndB;
        zIncrement = (currentZ - pointB.getZ()) / numberOfPointsBetweenAAndB;
        thisLoc = new Location(tempWorld, currentX, currentY, currentZ);
        timeIterated++;
    } else {
        currentX -= xIncrement;
        currentY -= yIncrement;
        currentZ -= zIncrement;
        thisLoc = new Location(tempWorld, currentX, currentY, currentZ);
    }

    Block block = tempWorld.getBlockAt(thisLoc);

    if (block.getType() != Material.AIR) {
        airOnly = false;
        if (!Raziel.isTransparent(block.getType())) {
            break VisibleCheck;
        }
    }

    for (Entity nearbyEntity : nearby) {
        if (nearbyEntity.getType() == EntityType.PLAYER && !nearbyEntity.equals(player)) {
            final LivingEntity living = (LivingEntity) nearbyEntity;
            final Location loc = nearbyEntity.getLocation();

        }
    }
}