TileEntity Class

public class TileEntityCPU extends TileEntity{


    //string list (replace references of this with yours)
    public List<String> stringList = new ArrayList<String>(9);


    public TileEntityCPU() {
        super();
        this.stringList.add(0, "1");
        this.stringList.add(1, "2");
        this.stringList.add(2, "3");
        this.stringList.add(3, "4");
        this.stringList.add(4, "5");
        this.stringList.add(5, "6");
        this.stringList.add(6, "7");
        this.stringList.add(7, "8");
        this.stringList.add(8, "9");
        System.out.println(this.stringList);
    }

    public String getLine(int line) {
        return this.stringList.get(line);
    }

    public void setLine(String code, int line) {
        this.stringList.set(line, code);
    }


    public void writeToNBT(NBTTagCompound comp)
    {
     super.writeToNBT(comp);
     NBTTagList tagList = new NBTTagList();
     for(int i = 0; i < stringList.size(); i++)
     {
      String s = stringList.get(i);
      if(s != null)
      {
       NBTTagCompound tag = new NBTTagCompound();
       tag.setString("Code" + i, s);
       tagList.appendTag(tag);
      }
     }
     comp.setTag("CodeList", tagList);
    }

    public void readFromNBT(NBTTagCompound comp)
    {
     super.readFromNBT(comp);
     NBTTagList tagList = comp.getTagList("CodeList", Constants.NBT.TAG_COMPOUND);
     for(int i = 0; i < tagList.tagCount(); i++)
     {
      NBTTagCompound tag = tagList.getCompoundTagAt(i);
      String s = tag.getString("Code" + i);
      stringList.add(i, s);
     }
    }

    public Container createContainer() {
        return new ContainerCPU();
    }

    @Override
    public void onDataPacket(NetworkManager net, S35PacketUpdateTileEntity pkt)
    {
        this.readFromNBT(pkt.getNbtCompound());
        this.markDirty();
    }

    public void update(World world) {
        worldObj.markBlockForUpdate(this.pos);
    }

}