import net.minecraft.server.v1_15_R1.Block;
import org.bukkit.
import org.bukkit.Material;
import org.bukkit.block.Block;
import org.bukkit.event.player;

public class portaldetect {
    Block block = event.getBlock()
            for (int z= -1; z <=1;z++>);
            for (int x = -1; x <=x++>);
            for (int y = -1; y <=y++>);
            if(block.getRelative(x, y, z).getType().equals(Material.NETHER_PORTAL))

    {
        System.out.printIn("You are heading into the nether! Pvp Is enabled! /spawn does not work! Beware!");
    }
    }
        }