Bukkit编程之动态向yml文件中添加属性

yaml = new Yaml();        
            String goods = args[0];
            String goodsNum = args[1];
            
            YamlConfiguration yc = new YamlConfiguration();
            try {
                yc.load(new File(System.getProperty("user.dir")+"/plugins/PbMainPlugin/configDef.yml"));
            } catch (FileNotFoundException e1) {
                
                e1.printStackTrace();
            } catch (IOException e1) {
                
                e1.printStackTrace();
            } catch (InvalidConfigurationException e1) {
                
                e1.printStackTrace();
            }
            
            Set set = yc.getConfigurationSection("drop").getKeys(false);
            
            lastDropNum = set.size();  //查看yml文件中是否有内容，没有内容返回0，否则返回内容长度
            
            player.sendMessage("大小是："+set.size()+"");
            player.sendMessage("内容是："+set+"");
            YamlConfiguration yamlConfiguration = new YamlConfiguration();
            if(lastDropNum==0) { //如果原来yml文件中没有内容

                ConfigurationSection drop = yamlConfiguration.createSection("drop");
                
                Map<String, Object> item = new HashMap();
                item.put("item-Id", Material.valueOf(goods.trim()).getId());
                item.put("item-Name", Material.valueOf(goods.trim()).name());
                drop.createSection("1",item);    
                try {
                    
                    yamlConfiguration.save(System.getProperty("user.dir")+"/plugins/PbMainPlugin/configDef.yml");
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                
            }
            
            if(lastDropNum!=0) { //如果yml中有内容，则向yml文件中追加新的内容
                yamlConfiguration = YamlConfiguration.loadConfiguration(new File(System.getProperty("user.dir")+"/plugins/PbMainPlugin/configDef.yml"));
                ConfigurationSection drop = yamlConfiguration.getConfigurationSection("drop");
                Map<String, Object> item = new HashMap();
                item.put("item-Id", Material.valueOf(goods.trim()).getId());
                item.put("item-Name", Material.valueOf(goods.trim()).name());
                drop.set((lastDropNum+1)+"", item);
                try {
                    yamlConfiguration.save(System.getProperty("user.dir")+"/plugins/PbMainPlugin/configDef.yml");
                } catch (IOException e) {
                    
                    e.printStackTrace();
                }

            }

            //向玩家背包中添加物品
            PlayerInventory inventory = player.getInventory();
            ItemStack itemStack = new ItemStack(Material.valueOf(goods.trim()),Integer.parseInt(goodsNum));
            inventory.addItem(itemStack);
            return true;

yml文件中的结构为：