get block on location

Hi
I'm writing om my first plugin right now and need some help.
he plugin i'm writing is a basic stuck plugin wich teleports you to the highest posible location above your head. I've selected to do it this way:

1. get location to comand sender
2. set the location to int values
3. change locy to 128
4. a while loop: as long as block on the location is air: locy++
5. set locx, locy and locz to a location
6. tp player to location

I'm having trouble with the while loop, I can't find a way to find what kind of block it is o given cordiantes, how should i do this?

PS: This is my first week with java and bukkit.

 

When you have got a Location-Object, you can simply just

Code:

Block b = location.getBlock();

 

hmm, tried it ant it seams to work, but when i try it in game i get teleportedt to my own location only on y 128
here is my onCommand:

Code:

        public boolean onCommand(CommandSender sender, Command cmd, String commandLabel, String[] args){
            String commandName = cmd.getName().toLowerCase();

            Player player = (Player) sender;
            World currentWorld = player.getWorld();
            if (commandName.equals("stuck")) {

                Location loc = player.getLocation();
                int locx = (int)loc.getX();
                int locy = 128;
                int locz = (int)loc.getZ();
                Location nloc = new Location(currentWorld, locx, locy, locz);
                Block b = nloc.getBlock();

                player.sendMessage("You are located at:" + locx + "," + locy + "," + locz);
                while(b.getType() == Material.AIR){
                    locy = locy++;
                    nloc = new Location(currentWorld, locx, locy, locz);
                }
                locy = locy+2;
                nloc = new Location(currentWorld, locx, locy, locz);
                player.teleportTo(nloc);
                player.sendMessage("you should now have been teleported");
                return true;
            } else {
                player.sendMessage("That was not a valid command");

            }
            return true;
        }

 

Seems right, just the contents of the while-loop are false:

Code:

while(b.getType().equals(Material.AIR)){
    locy--;
    nloc.setY(locy);
    b = nloc.getBlock();
}

1. In Java, you can't compare two objects with the == operator. You have to use the method Object.equals(Object other), like I did in the condition of the while-loop
2. you want to go down on the y-axis, so do just locy-- and not locy = locy --
3. You can modify the Y-coordinate of the location object by doing .setY(the-y-coord)
4. you have to update the block after you updated the location. If you don't do this, it will run into an endless loop

 

thank you!
But it's still something wrong, I just get teleported to y 128.
here is my onCommand:

Code:

        public boolean onCommand(CommandSender sender, Command cmd, String commandLabel, String[] args){
            String commandName = cmd.getName().toLowerCase();

            Player player = (Player) sender;
            World currentWorld = player.getWorld();
            if (commandName.equals("stuck")) {

                Location loc = player.getLocation();
                int locx = (int)loc.getX();
                int locy = 128;
                int locz = (int)loc.getZ();
                Location nloc = new Location(currentWorld, locx, locy, locz);
                Block b = nloc.getBlock();

                player.sendMessage("You are located at:" + locx + "," + locy + "," + locz);
                while(b.getType().equals(Material.AIR)){
                    locy--;
                    nloc.setY(locy);
                    b = nloc.getBlock();
                }
                locy = locy+2;
                nloc.setY(locy);
                player.teleportTo(nloc);
                player.sendMessage("you should now have been teleported");
                return true;
            } else {
                player.sendMessage("That was not a valid command");

            }
            return true;
        }

thank you for your time(and for theaching me java =)

 

Maybe it's also the wrong start value for y? Because the y-coord in mine craft just ranges from 0-127.
Ah, now it's getting clearer.
Minecraft tells that blocks above 127 have got the type Bedrock. So the while loop will never run it's contents
Just do int locy = 127; and it should be fine.

 

YES!
got it to work, did some other changes than locy = 127, her is the final onCommand:

Code:

        public boolean onCommand(CommandSender sender, Command cmd, String commandLabel, String[] args){
            String commandName = cmd.getName().toLowerCase();

            Player player = (Player) sender;
            World currentWorld = player.getWorld();
            if (commandName.equals("stuck")) {

                Location loc = player.getLocation();
                int locx = (int)loc.getX();
                int locy = 127;
                int locz = (int)loc.getZ();
                Location nloc = new Location(currentWorld, locx, locy, locz);
                Block b = nloc.getBlock();

                do{
                    locy--;
                    nloc.setY(locy);
                    b = nloc.getBlock();
                    if(!b.getType().equals(Material.AIR)){
                        double flocx = nloc.getX();
                        double flocy = nloc.getY();
                        double flocz = nloc.getZ();
                        flocx = flocx+0.5;
                        flocz = flocz+0.5;
                        flocy = flocy+2.0;
                        Location floc = new Location(currentWorld, flocx, flocy, flocz);
                        player.teleportTo(floc);
                        player.sendMessage("you should now have been teleported");
                        }
                    }while(b.getType().equals(Material.AIR));

                return true;
            } else {
                player.sendMessage("That was not a valid command");

            }
            return true;
        }

thank you so much!

 

There's a World.getHighestBlockYAt (int x, int z) and World.getHighestBlockYAt (Location location) method.

 

It's better to code that yourself, to get more experience

 

@Shamebot
i did not know that.

 

@narrowtux These methods should be way faster because they use the minecraft highmap, I think.
Also I think he doesn't need the if block in the loop, he could just do the stuff below it and he should use (I think it's) World.getTypeIdAt(...) because it's uncached.

 

I don't think you have to look at performance when performing a command and a while-loop that has a maximum of 128 runs.

 

True but as said the blocks get cached and I always try to save some performance rather than loosing a bit here and there and it sums up.

 

We've got high-performance CPUs with multicore and 2+ GHz for this. This short lookup will take the processor somewhat about ~100µs, if not less.

 

@Shamebot
I know i don't need the if block in the while loop, but for some reason i like doing it that way.