Develop Reference

Minecraft add new potion effects from custom potion effect

Currently trying to create a potion effect that once it runs out of time, applies other potion effects to the player. Seemed simple enough yet I found a few errors and bugs trying to accomplish this,
Directly trying to add the effect
#Override
public void performEffect(EntityLivingBase entity, int amplifier){
if (entity instanceof EntityPlayer)
{
EntityPlayer player = (EntityPlayer)entity;
if(player != null){
if(player.getActivePotionEffect(PotionRegistry.effectBuzz) != null){
int duraction = player.getActivePotionEffect(PotionRegistry.effectBuzz).getDuration();
if(duration <= 2){
player.addPotionEffect(new PotionEffect(MobEffects.WEAKNESS, 1200));
}
}
}
}
}
Needless to say this produces this error
[16:10:04] [Server thread/ERROR]: Encountered an unexpected exception
net.minecraft.util.ReportedException: Ticking player
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:212)
~[NetworkSystem.class:?]
at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:807)
~[MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:688)
~[MinecraftServer.class:?]
at net.minecraft.server.integrated.IntegratedServer.tick(IntegratedServer.java:156)
~[IntegratedServer.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:537)
[MinecraftServer.class:?]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_161]
Caused by: java.util.ConcurrentModificationException
at java.util.HashMap$HashIterator.nextNode(Unknown Source) ~[?:1.8.0_161]
at java.util.HashMap$KeyIterator.next(Unknown Source) ~[?:1.8.0_161]
at net.minecraft.entity.EntityLivingBase.updatePotionEffects(EntityLivingBase.java:650)
~[EntityLivingBase.class:?]
at net.minecraft.entity.EntityLivingBase.onEntityUpdate(EntityLivingBase.java:383)
~[EntityLivingBase.class:?]
at net.minecraft.entity.Entity.onUpdate(Entity.java:436) ~[Entity.class:?]
at net.minecraft.entity.EntityLivingBase.onUpdate(EntityLivingBase.java:2144)
~[EntityLivingBase.class:?]
at net.minecraft.entity.player.EntityPlayer.onUpdate(EntityPlayer.java:260)
~[EntityPlayer.class:?]
at net.minecraft.entity.player.EntityPlayerMP.onUpdateEntity(EntityPlayerMP.java:345)
~[EntityPlayerMP.class:?]
at net.minecraft.network.NetHandlerPlayServer.update(NetHandlerPlayServer.java:174)
~[NetHandlerPlayServer.class:?]
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.update(NetworkDispatcher.java:216)
~[NetworkDispatcher$1.class:?]
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:309)
~[NetworkManager.class:?]
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:197)
~[NetworkSystem.class:?]
... 5 more
Where as if I run this in a tick event
In CommonProxy
MinecraftForge.EVENT_BUS.register(new EventManager());
And then For the EventManager itself
public class EventManager {
public static PotionEffect potion = new PotionEffect(MobEffects.WEAKNESS, 1200);
public static PotionEffect potion2 = new PotionEffect(MobEffects.HUNGER, 600);
public static PotionEffect potion3 = new PotionEffect(MobEffects.UNLUCK, 1200);
#SubscribeEvent
public void onTick(WorldTickEvent event){
EntityPlayer player = Minecraft.getMinecraft().thePlayer;
World world = Minecraft.getMinecraft().theWorld;
if(player != null){
boolean hasEffect = player.isPotionActive(PotionRegistry.effectBuzz);
int applyIt = 0;
if(hasEffect){
applyIt = 1;
} else if(!player.isPotionActive(potion.getPotion()) && applyIt == 1){
applyIt = 2;
} else {
applyIt = 0;
}
if(player != null && applyIt == 2){
player.addPotionEffect(potion);
}
}
}
}
This works, yet the effects are infinite.

You're performing your action whilst the potion effects are being looped. This is akin to modifying an array whilst iterating it. Don't do that.
Also, don't perform actions like potion effects client side.
The ONLY thing to do client side is graphics and user input/output.
Things like potions must be handled on the server, otherwise the server will overwrite your actions on the next update packet.
Just set a flag in your ExtendPlayer entity, and then onTick or player update event check for that flag existance and then add the potions.
#Override
public void performEffect(EntityLivingBase entity, int amplifier){
if (entity instanceof EntityPlayer)
{
EntityPlayer player = (EntityPlayer)entity;
if(player != null){
if(player.getActivePotionEffect(PotionRegistry.effectBuzz) != null){
int duraction = player.getActivePotionEffect(PotionRegistry.effectBuzz).getDuration();
if(duration <= 2){
ExtendedPlayer ePlayer = ExtendedPlayer.get(player);
ePlayer.enableBuzz();
}
}
}
}
}
Something akin to your Extended player
public class ExtendedPlayer implements IExtendedEntityProperties {
... Extended player setup here
protected boolean startBuzz = false;
public void enableBuzz()
{
this.startBuzz = true;
}
public static final ExtendedPlayer get(EntityPlayer player) {
return (ExtendedPlayer) player.getExtendedProperties("MuddymansExtendedPlayer");
}
public EntityPlayer getPlayer() {
return this.player;
}
/**
* Updates anything that needs to be updated each tick
* NOT called automatically, so you must call it yourself from LivingUpdateEvent or a TickHandler
*/
public void onUpdate() {
if(!player.worldObj.isRemote) {
if(this.enableBuzz) {
Player player = this.getPlayer()
player.addPotionEffect(new PotionEffect(MobEffects.WEAKNESS, 1200));
player.addPotionEffect(new PotionEffect(MobEffects.HUNGER, 600));
player.addPotionEffect(new PotionEffect(MobEffects.UNLUCK, 1200));
this.startBuzz = false;
}
}
}
}
Call the exteded player update event from an event handler
#SubscribeEvent
public void livingTick(final LivingUpdateEvent event) {
if (event.entity != null && event.entity instanceof EntityPlayer) {
if(!event.entity.isDead) {
ExtendedPlayer.get((EntityPlayer)event.entity).onUpdate();
}
}

Inventory ClickEvent not working

When I click the Item in the Inventory, it simply does nothing and I can drag it anywhere I want. Then I re-open the inventory and the Item is back. I want the item a click (The Notify item in this case) to toggle the notify boolean and close the Inventory. Please help. It may be a stupid solution but sometimes the simple stuff can escape me. Thanks.
This is the Inventory:
public class GUI extends JavaPlugin implements Listener
{
private API api;
AlphaCommand command = new AlphaCommand();
public static Inventory inv = Bukkit.createInventory(null, 9, ChatColor.AQUA + "Alpha Config");
public static boolean isNotifyEnabled()
{
return AlphaCommand.notify;
}
protected String getCheckName()
{
return this.getCheckName();
}
public static void openGUI(Player player, Inventory inv)
{
ItemStack checks = new ItemStack(Material.DIAMOND_SWORD);
ItemStack banPlayer = new ItemStack(Material.GOLD_AXE);
ItemStack autoBan = new ItemStack(Material.DIAMOND_AXE);
ItemStack notify = new ItemStack(Material.SLIME_BALL);
ItemMeta checksMeta = checks.getItemMeta();
ItemMeta autoBanMeta = autoBan.getItemMeta();
ItemMeta notifyMeta = notify.getItemMeta();
ItemMeta banPlayerMeta = banPlayer.getItemMeta();
checksMeta.setDisplayName(ChatColor.BLUE + "Checks");
autoBanMeta.setDisplayName(ChatColor.BLUE + "AutoBan");
notifyMeta.setDisplayName(ChatColor.BLUE + "Notify");
banPlayerMeta.setDisplayName(ChatColor.BLUE + "Ban Player");
checks.setItemMeta(checksMeta);
autoBan.setItemMeta(autoBanMeta);
notify.setItemMeta(notifyMeta);
banPlayer.setItemMeta(banPlayerMeta);
inv.setItem(7, banPlayer);
inv.setItem(1, checks);
inv.setItem(3, autoBan);
inv.setItem(5, notify);
player.openInventory(inv);
}
public static void open(Player player, Inventory inv)
{
if(player instanceof Player)
{
player.openInventory(inv);
}
}
public static Inventory getGUI(){
return inv;
}
#EventHandler
public void onInventoryClick(InventoryClickEvent e)
{
Bukkit.getPluginManager().registerEvents(this, Bukkit.getPluginManager().getPlugins()[0]);
String invName = ChatColor.stripColor(e.getClickedInventory().getName());
Player player = (Player) e.getWhoClicked(); // The player that clicked the item
ItemStack clicked = e.getCurrentItem(); // The item that was clicked
#SuppressWarnings("unused")
Inventory inventory = e.getInventory(); // The inventory that was clicked in
if(invName.equalsIgnoreCase(inv.getName()))
{
if((clicked == null) || (clicked.getType() == Material.AIR) || (!clicked.hasItemMeta()))
{
player.closeInventory();
return;
}
if(clicked.getItemMeta().getDisplayName().equalsIgnoreCase("AutoBan"))
{
Configuration config = this.api.getConfiguration();
boolean autoBan = config.readBoolean("checks." + getCheckName() + ".AutoBan");
if (config.readBoolean("checks." + getCheckName() + ".AutoBan") == true)
{
autoBan = false;
e.setCancelled(true);
player.closeInventory();
return;
}
else if(autoBan == false)
{
autoBan = true;
e.setCancelled(true);
player.closeInventory();
return;
}
else
{
e.setCancelled(true);
player.closeInventory();
return;
}
}
if(clicked.getItemMeta().getDisplayName().equalsIgnoreCase("Notify"))
{
boolean notify = isNotifyEnabled();
if(notify == true)
{
notify = false;
e.setCancelled(true);
player.closeInventory();
return;
}
else if(notify == false)
{
notify = true;
e.setCancelled(true);
player.closeInventory();
return;
}
}
if(clicked.getItemMeta().getDisplayName().equalsIgnoreCase("Checks"))
{
player.sendMessage(ChatColor.RED + "This Feature is coming soon to Alpha.");
e.setCancelled(true);
player.closeInventory();
return;
}
if(e.getCurrentItem().getItemMeta().getDisplayName().equalsIgnoreCase("Ban Player"))
{
player.sendMessage("This Feature is coming soon to Alpha V.4");
e.setCancelled(true);
player.closeInventory();
return;
}else
{
player.closeInventory();
e.setCancelled(true);
return;
}
}
}
}

There seems to be multiple issues in the code that you have provided above that will cause the expected result to not be seen.
#1
Firstly you register the events for this class, inside the event itself, which means it'll never get registered unless the event get's called, which will never happen unless you register it... See the problem? So what you need to do is move the following line of code into your onEnable method.
Bukkit.getPluginManager().registerEvents(this, Bukkit.getPluginManager().getPlugins()[0]);
You need to make a few changes to this line of code. You need to replace this with a new instance of the listener object, new GUI(). It's also recommended that you register the listener with the plugin that your calling it from, but fortunately, if you put this in your onEnable, your onEnable method is inside your plugin class. This means that you can change your plugin to this. You new line of code will look like this.
Bukkit.getPluginManager().registerEvents(new GUI(), this);
Put that in your onEnable and that issue here should be resolved.
#2
The second issue is that when you're checking your item names and you're not stripping colour. This get's rid of an colours in the string. This is because your item names are ChatColor.BLUE + "AutoBan" however you're checking if it equals "AutoBan" which is different. All you need to do to fix this issue is exactly the same with what you did with the inventory name, and use ChatColor.stripColor(itemName) to get a string you can check against.
For example:
String itemName = ChatColor.stripColor(clicked.getItemMeta().getDisplayName());
if (itemName.equals("AutoBan")){
Note: I also replaced equalsIgnoreCase with equals as the cases always matched, so was an unnecessary check.

How to check if a player right-clicked another player

Looking for the right event to work with. I want to check if a player right-clicked another player.
This is what i have so far (doesn't work. Not getting into the if or the else statement:
public void onPlayerRightClicks(PlayerInteractEntityEvent e) {
Player p=e.getPlayer();
if(e.getRightClicked() instanceof Player) p.sendMessage("You have rightclicked a player.");
else p.sendMessage("You didn't hit anyone with your spell");
}

Found the answer to the question by combining my own code with codes from another answer on a similar question:
#SuppressWarnings("deprecation")
#EventHandler
public void onPlayerClick(PlayerInteractEvent e) {
Player p=e.getPlayer();
NBTItem item = new NBTItem(p.getItemInHand());
Entity en=getNearestEntityInSight(p,5);
if(e.getAction()==Action.RIGHT_CLICK_AIR && en instanceof Player) p.sendMessage("You have rightclicked a player.");
else p.sendMessage("You didn't hit anyone with your spell");
}
public static Entity getNearestEntityInSight(Player player, int range) {
ArrayList<Entity> entities = (ArrayList<Entity>) player.getNearbyEntities(range, range, range);
ArrayList<Block> sightBlock = (ArrayList<Block>) player.getLineOfSight(null, range);
ArrayList<Location> sight = new ArrayList<Location>();
for (int i = 0;i<sightBlock.size();i++)
sight.add(sightBlock.get(i).getLocation());
for (int i = 0;i<sight.size();i++) {
for (int k = 0;k<entities.size();k++) {
if (Math.abs(entities.get(k).getLocation().getX()-sight.get(i).getX())<1.3) {
if (Math.abs(entities.get(k).getLocation().getY()-sight.get(i).getY())<1.5) {
if (Math.abs(entities.get(k).getLocation().getZ()-sight.get(i).getZ())<1.3) {
return entities.get(k);
}
}
}
}
}
return null;
}
Even though it works, i don't think it's an optimal answer, as there should be an event that can check whether or not a player rightclicked or at least leftclicked another player. The getNearestEntitySight method finds the closest entity in the player's sight. I combined it with my code which runs when a player rightclicks, using the PlayerInteractEvent.

Try this:
#EventHandler
public void onPlayerInteractEntity(final PlayerInteractAtEntityEvent e) {
final Player p = e.getPlayer();
if (e.getRightClicked() instanceof Player) {
final Player clicked = (Player) e.getRightClicked();
// DO STUFF
}
}

BlueJ - easy painting program | if-funktion (sum.kern)

I'm having a problem with the if-funktion.
It should be:
If (mouse is pressed) the pencil should follow the cursor and paint the way
else do nothing.
That is my code. Can not find the error
import sum.kern.*;
public class ZeichnePrgm
{
// Objects
Bildschirm derBildschirm;
Stift derStift;
Maus dieMaus;
// Konstruktor
public ZeichnePrgm()
{
derBildschirm = new Bildschirm();
derStift = new Stift();
dieMaus = new Maus();
}
// Dienste
public void fuehreAus()
{
do
{
if(dieMaus.istGedrueckt()) // mouse.isPressed
{
derStift.bewegeBis(dieMaus.hPosition(),dieMaus.vPosition()); //pen.moveTo
derStift.runter(); // pen.down
}
else
derStift.hoch(); //pen.up
}while(dieMaus.doppelKlick()); //pen.doubleClick
/* while(!dieMaus.doppelKlick())
*
* meinStift.runter(); // pen.down
* meinStift.bewegeBis(dieMaus.hPosition(),dieMaus.vPosition()); //pen.moveTo
*/
}
}

How to convert a block into its class -Canarymod

I have been programming a plugin to move someone up when they right click a sign with certain text on on it but to find the text I need to convert the Block class to the sign class and use the getTextOnLine(); function here is my Java code
public class CowShooter extends EZPlugin implements PluginListener {
#Override
public boolean enable() {
Canary.hooks().registerListener(this, this);
return super.enable(); // Call parent class's version too.
}
#HookHandler
public void SignChangeHook(BlockRightClickHook event) {
Player player = event.getPlayer();
Block block = event.getBlockClicked();
if (block.getType() == BlockType.SignPost || block.getType() == BlockType.WallSign) {
Bad code
Sign sign = event.getBlockClicked();
if (sign.getTextOnLine(1) == "TP") {
Location loc = player.getLocation();
int playerX = (int) loc.getX();
int playerY = (int) loc.getY();
int playerZ = (int) loc.getZ();
loc.setY(playerY+10);
player.teleportTo(loc);
}
}
}
}
Here is the folder that the source code is in Source code for canarymod

Get the co-ordinates of the block and set them in the sign class
Location loc = player.getLocation();
loc.setX(event.getBlockClicked().getX());
loc.setZ(event.getBlockClicked().getZ());
loc.setY(event.getBlockClicked().getY());
World world = loc.getWorld();
Sign sign = (Sign)world.getTileEntity(world.getBlockAt(loc));