Paper/src/main/java/net/minecraft/server/Packet.java

package net.minecraft.server;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public abstract class Packet {

    public static IntHashMap j = new IntHashMap();
    private static Map a = new HashMap();
    private static Set b = new HashSet();
    private static Set c = new HashSet();
    public final long timestamp = System.currentTimeMillis();
    public boolean lowPriority = false;

    public Packet() {}

    static void a(int i, boolean flag, boolean flag1, Class oclass) {
        if (j.b(i)) {
            throw new IllegalArgumentException("Duplicate packet id:" + i);
        } else if (a.containsKey(oclass)) {
            throw new IllegalArgumentException("Duplicate packet class:" + oclass);
        } else {
            j.a(i, oclass);
            a.put(oclass, Integer.valueOf(i));
            if (flag) {
                b.add(Integer.valueOf(i));
            }

            if (flag1) {
                c.add(Integer.valueOf(i));
            }
        }
    }

    public static Packet a(int i) {
        try {
            Class oclass = (Class) j.get(i);

            return oclass == null ? null : (Packet) oclass.newInstance();
        } catch (Exception exception) {
            exception.printStackTrace();
            System.out.println("Skipping packet with id " + i);
            return null;
        }
    }

    public final int b() {
        return ((Integer) a.get(this.getClass())).intValue();
    }

    // CraftBukkit - throws IOException
    public static Packet a(DataInputStream datainputstream, boolean flag) throws IOException {
        boolean flag1 = false;
        Packet packet = null;

        int i;

        try {
            i = datainputstream.read();
            if (i == -1) {
                return null;
            }

            if (flag && !c.contains(Integer.valueOf(i)) || !flag && !b.contains(Integer.valueOf(i))) {
                throw new IOException("Bad packet id " + i);
            }

            packet = a(i);
            if (packet == null) {
                throw new IOException("Bad packet id " + i);
            }

            packet.a(datainputstream);
        } catch (EOFException eofexception) {
            System.out.println("Reached end of stream");
            return null;
        }

        // CraftBukkit start
        catch (java.net.SocketTimeoutException exception) {
            System.out.println("Read timed out");
            return null;
        } catch (java.net.SocketException exception) {
            System.out.println("Connection reset");
            return null;
        }
        // CraftBukkit end

        PacketCounter.a(i, (long) packet.a());
        return packet;
    }

    // CraftBukkit - throws IOException
    public static void a(Packet packet, DataOutputStream dataoutputstream) throws IOException {
        dataoutputstream.write(packet.b());
        packet.a(dataoutputstream);
    }

    // CraftBukkit - throws IOException
    public static void a(String s, DataOutputStream dataoutputstream) throws IOException {
        if (s.length() > 32767) {
            throw new IOException("String too big");
        } else {
            dataoutputstream.writeShort(s.length());
            dataoutputstream.writeChars(s);
        }
    }

    // CraftBukkit - throws IOException
    public static String a(DataInputStream datainputstream, int i) throws IOException {
        short short1 = datainputstream.readShort();

        if (short1 > i) {
            throw new IOException("Received string length longer than maximum allowed (" + short1 + " > " + i + ")");
        } else if (short1 < 0) {
            throw new IOException("Received string length is less than zero! Weird string!");
        } else {
            StringBuilder stringbuilder = new StringBuilder();

            for (int j = 0; j < short1; ++j) {
                stringbuilder.append(datainputstream.readChar());
            }

            return stringbuilder.toString();
        }
    }

    public abstract void a(DataInputStream datainputstream) throws IOException; // CraftBukkit

    public abstract void a(DataOutputStream dataoutputstream) throws IOException; // CraftBukkit

    public abstract void handle(NetHandler nethandler);

    public abstract int a();

    protected ItemStack b(DataInputStream datainputstream) throws IOException { // CraftBukkit
        ItemStack itemstack = null;
        short short1 = datainputstream.readShort();

        if (short1 >= 0) {
            byte b0 = datainputstream.readByte();
            short short2 = datainputstream.readShort();

            itemstack = new ItemStack(short1, b0, short2);
            if (Item.byId[short1].g() || Item.byId[short1].i()) {
                itemstack.tag = this.c(datainputstream);
            }
        }

        return itemstack;
    }

    protected void a(ItemStack itemstack, DataOutputStream dataoutputstream) throws IOException { // CraftBukkit
        if (itemstack == null || itemstack.id <= 0) { // CraftBukkit
            dataoutputstream.writeShort(-1);
        } else {
            dataoutputstream.writeShort(itemstack.id);
            dataoutputstream.writeByte(itemstack.count);
            dataoutputstream.writeShort(itemstack.getData());
            if (itemstack.getItem().g() || itemstack.getItem().i()) {
                this.a(itemstack.tag, dataoutputstream);
            }
        }
    }

    protected NBTTagCompound c(DataInputStream datainputstream) throws IOException { // CraftBukkit
        short short1 = datainputstream.readShort();

        if (short1 < 0) {
            return null;
        } else {
            byte[] abyte = new byte[short1];

            datainputstream.readFully(abyte);
            return NBTCompressedStreamTools.a(abyte);
        }
    }

    protected void a(NBTTagCompound nbttagcompound, DataOutputStream dataoutputstream) throws IOException { // CraftBukkit
        if (nbttagcompound == null) {
            dataoutputstream.writeShort(-1);
        } else {
            byte[] abyte = NBTCompressedStreamTools.a(nbttagcompound);

            dataoutputstream.writeShort((short) abyte.length);
            dataoutputstream.write(abyte);
        }
    }

    static {
        a(0, true, true, Packet0KeepAlive.class);
        a(1, true, true, Packet1Login.class);
        a(2, true, true, Packet2Handshake.class);
        a(3, true, true, Packet3Chat.class);
        a(4, true, false, Packet4UpdateTime.class);
        a(5, true, false, Packet5EntityEquipment.class);
        a(6, true, false, Packet6SpawnPosition.class);
        a(7, false, true, Packet7UseEntity.class);
        a(8, true, false, Packet8UpdateHealth.class);
        a(9, true, true, Packet9Respawn.class);
        a(10, true, true, Packet10Flying.class);
        a(11, true, true, Packet11PlayerPosition.class);
        a(12, true, true, Packet12PlayerLook.class);
        a(13, true, true, Packet13PlayerLookMove.class);
        a(14, false, true, Packet14BlockDig.class);
        a(15, false, true, Packet15Place.class);
        a(16, false, true, Packet16BlockItemSwitch.class);
        a(17, true, false, Packet17EntityLocationAction.class);
        a(18, true, true, Packet18ArmAnimation.class);
        a(19, false, true, Packet19EntityAction.class);
        a(20, true, false, Packet20NamedEntitySpawn.class);
        a(21, true, false, Packet21PickupSpawn.class);
        a(22, true, false, Packet22Collect.class);
        a(23, true, false, Packet23VehicleSpawn.class);
        a(24, true, false, Packet24MobSpawn.class);
        a(25, true, false, Packet25EntityPainting.class);
        a(26, true, false, Packet26AddExpOrb.class);
        a(28, true, false, Packet28EntityVelocity.class);
        a(29, true, false, Packet29DestroyEntity.class);
        a(30, true, false, Packet30Entity.class);
        a(31, true, false, Packet31RelEntityMove.class);
        a(32, true, false, Packet32EntityLook.class);
        a(33, true, false, Packet33RelEntityMoveLook.class);
        a(34, true, false, Packet34EntityTeleport.class);
        a(38, true, false, Packet38EntityStatus.class);
        a(39, true, false, Packet39AttachEntity.class);
        a(40, true, false, Packet40EntityMetadata.class);
        a(41, true, false, Packet41MobEffect.class);
        a(42, true, false, Packet42RemoveMobEffect.class);
        a(43, true, false, Packet43SetExperience.class);
        a(50, true, false, Packet50PreChunk.class);
        a(51, true, false, Packet51MapChunk.class);
        a(52, true, false, Packet52MultiBlockChange.class);
        a(53, true, false, Packet53BlockChange.class);
        a(54, true, false, Packet54PlayNoteBlock.class);
        a(60, true, false, Packet60Explosion.class);
        a(61, true, false, Packet61WorldEvent.class);
        a(70, true, false, Packet70Bed.class);
        a(71, true, false, Packet71Weather.class);
        a(100, true, false, Packet100OpenWindow.class);
        a(101, true, true, Packet101CloseWindow.class);
        a(102, false, true, Packet102WindowClick.class);
        a(103, true, false, Packet103SetSlot.class);
        a(104, true, false, Packet104WindowItems.class);
        a(105, true, false, Packet105CraftProgressBar.class);
        a(106, true, true, Packet106Transaction.class);
        a(107, true, true, Packet107SetCreativeSlot.class);
        a(108, false, true, Packet108ButtonClick.class);
        a(130, true, true, Packet130UpdateSign.class);
        a(131, true, false, Packet131ItemData.class);
        a(200, true, false, Packet200Statistic.class);
        a(201, true, false, Packet201PlayerInfo.class);
        a(250, true, true, Packet250CustomPayload.class);
        a(254, false, true, Packet254GetInfo.class);
        a(255, true, true, Packet255KickDisconnect.class);
    }
}