Question

我目前正与其他几个人一起制作Bukkit插件，并且我正在尝试创建一个日志系统。我一直试图修复我破损的代码2天，但一无所获。它似乎陷入困境的部分是我获取插件的数据文件夹，所以我可以继续写入文件夹中的文件。

堆栈跟踪：

[18:41:07] [Server thread/ERROR]: Error occurred while enabling TownyEco v1.0-SNAPSHOT (Is it up to date?)
java.lang.ExceptionInInitializerError: null
    at com.writedive.townyeco.TownyEco.onEnable(TownyEco.java:67) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:264) ~[spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:337) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:403) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugin(CraftServer.java:381) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at org.bukkit.craftbukkit.v1_12_R1.CraftServer.enablePlugins(CraftServer.java:330) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at net.minecraft.server.v1_12_R1.MinecraftServer.t(MinecraftServer.java:422) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at net.minecraft.server.v1_12_R1.MinecraftServer.l(MinecraftServer.java:383) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at net.minecraft.server.v1_12_R1.MinecraftServer.a(MinecraftServer.java:338) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:272) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:545) [spigot-1.12.2.jar:git-Spigot-4bd94dc-fb414fe]
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161]
Caused by: java.lang.NullPointerException
    at com.writedive.townyeco.messaging.TELogWriter.getRootFolder(TELogWriter.java:12) ~[?:?]
    at com.writedive.townyeco.messaging.TELogWriter.<clinit>(TELogWriter.java:14) ~[?:?]
    ... 12 more

来自的错误：

private static TownyEco plugin;
private static String getRootFolder() {
    return plugin.getDataFolder().getPath();
}
private static String PATH = getRootFolder() + File.separator + "logs";

在主类的内部，从onEnable引用的记录器：

TELogWriter.log("Initialized", TELogWriter.LogType.STARTUP);

我该怎么做才能解决这个问题？

主要班级：TownyEco.java

记录器类：TELogWriter.java

Answer 1

TELogWriter中的

插件永远不会被初始化，因此下面的代码会抛出NPE

private static String getRootFolder() {
    return plugin.getDataFolder().getPath();
}

在TownyEco.java中初始化TELogWriter.plugin然后调用日志

TELogWriter.plugin = plugin;
TELogWriter.log("Initialized", TELogWriter.LogType.STARTUP);

Answer 2

不熟悉您正在使用的API，但

A）如果getDataFolder（）有时仅由于不一致而返回null

private static String getRootFolder() {
    FolerObjectTypeOfTheAPI path;
    if (plugin != null && (path = plugin.getDataFolder()) != null)  {
        return path.getPath();
    }
    return null; // or you can return "";
}

B）如果总是为null，那么“getDataFolder（）”中指定的路径很可能不是文件系统上的正确路径

插件getDataFolder空指针

2 个答案: