BlockedList

BlockedList.java

package li.angu.youtube.tutorial.block;

import org.bukkit.Material;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by finreinhard on 18.01.17.
 */
public class BlockedList {

    private static BlockedList instance;

    private List<Material> blocks;
    private List<String> commands;

    private BlockedList() {
        instance = this;

        this.blocks = new ArrayList<>();
        this.commands = new ArrayList<>();

        fillWithTestData();
    }

    public static BlockedList getInstance() {
        return instance == null ? new BlockedList() : instance;
    }

    public void fillWithTestData() {
        blocks.add(Material.TNT);
        blocks.add(Material.GRASS);
        blocks.add(Material.BEDROCK);

        commands.add("op");
        commands.add("deop");
    }

    public boolean isBlockBlocked(Material material) {
        return blocks.contains(material);
    }

    public boolean isCommandBlocked(String command) {
        // /op Firei

        /*
        Java 6+7

        for(String blockedCommand : this.commands) {
            if(command.toLowerCase().startsWith("/" + blockedCommand)) {
                return true;
            }
        }
        return false;
        */


        // Java 8
        return this.commands.stream().filter(
                blockedCommand -> command.toLowerCase().startsWith("/" + blockedCommand))
                .findFirst().orElse(null) != null;
    }

    public void addBlock(Material material) {
        this.blocks.add(material);
    }

    public void addCommand(String command) {
        this.commands.add(command);
    }

    public void removeBlock(Material material) {
        if (!this.blocks.contains(material)) {
            return;
        }
        this.blocks.remove(material);
    }

    public void removeCommand(String command) {
        if (!this.commands.contains(command)) {
            return;
        }

        this.commands.remove(command);
    }
}

BlockedListListener.java

package li.angu.youtube.tutorial.block;

import net.md_5.bungee.api.ChatColor;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.BlockPlaceEvent;
import org.bukkit.event.player.PlayerCommandPreprocessEvent;

/**
 * Created by finreinhard on 18.01.17.
 */
public class BlockedListListener implements Listener {

    @EventHandler
    public void onBlockPlace(BlockPlaceEvent event) {
        if (BlockedList.getInstance().isBlockBlocked(event.getBlock().getType())) {
            event.setCancelled(true);
            event.getPlayer().sendMessage(ChatColor.RED + "Diesen Block darfst du nicht platzieren!");
        }
    }

    @EventHandler
    public void onPlayerCommandPreprocess(PlayerCommandPreprocessEvent event) {
        if (BlockedList.getInstance().isCommandBlocked(event.getMessage())) {
            event.setCancelled(true);
            event.getPlayer().sendMessage(ChatColor.RED + "Diesen Befehl darfst du nicht ausführen!");
        }
    }
}