Plugin getting corrupted after download from Dropbox to plugins folder!!

I keep getting this error after downloading the plugin after updating from my Dropbox it uses a command to download the plugin into the plugin folder. I'm not completely sure whats wrong it worked before when I used 1.8.

Code:

[19:13:25 ERROR]: Could not load 'plugins\ObsidianCore.jar' in folder 'plugins'
org.bukkit.plugin.InvalidDescriptionException: Invalid plugin.yml
        at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:162) ~[spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:133) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.craftbukkit.v1_9_R1.CraftServer.loadPlugins(CraftServer.java:296) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.craftbukkit.v1_9_R1.CraftServer.reload(CraftServer.java:743) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.Bukkit.reload(Bukkit.java:539) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:25) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at org.bukkit.craftbukkit.v1_9_R1.CraftServer.dispatchCommand(CraftServer.java:645) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.PlayerConnection.handleCommand(PlayerConnection.java:1350) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.PlayerConnection.a(PlayerConnection.java:1185) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.PacketPlayInChat.a(PacketPlayInChat.java:45) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.PacketPlayInChat.a(PacketPlayInChat.java:1) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.PlayerConnectionUtils$1.run(SourceFile:13) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [?:1.8.0_25]
        at java.util.concurrent.FutureTask.run(Unknown Source) [?:1.8.0_25]
        at net.minecraft.server.v1_9_R1.SystemUtils.a(SourceFile:45) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.MinecraftServer.D(MinecraftServer.java:721) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.DedicatedServer.D(DedicatedServer.java:400) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.MinecraftServer.C(MinecraftServer.java:660) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at net.minecraft.server.v1_9_R1.MinecraftServer.run(MinecraftServer.java:559) [spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_25]
Caused by: java.util.zip.ZipException: zip file is empty
        at java.util.zip.ZipFile.open(Native Method) ~[?:1.8.0_25]
        at java.util.zip.ZipFile.<init>(Unknown Source) ~[?:1.8.0_25]
        at java.util.zip.ZipFile.<init>(Unknown Source) ~[?:1.8.0_25]
        at java.util.jar.JarFile.<init>(Unknown Source) ~[?:1.8.0_25]
        at java.util.jar.JarFile.<init>(Unknown Source) ~[?:1.8.0_25]
        at org.bukkit.plugin.java.JavaPluginLoader.getPluginDescription(JavaPluginLoader.java:150) ~[spigot-1.9.2.jar:git-Spigot-944aa20-420b983]
        ... 20 more

Download Code:

Code:

public static void dlFile(String DLURL, String FileName) throws IOException {

        URL url = new URL(DLURL);
        InputStream is = null;
        OutputStream os = null;
        try {
            os = new FileOutputStream(new File(FileName));
            is = url.openStream();
        } catch (IOException exp) {
            exp.printStackTrace();
        } finally {
            try {
                is.close();
            } catch (Exception exp) {
            }
            try {
                os.close();
            } catch (Exception exp) {
                exp.printStackTrace();
            }
        }
    }

Command Code:

Code:

if (args[0].equalsIgnoreCase("update")) {
                sender.sendMessage("§2§l** §aUpdating ObsidianCore...");

                Bukkit.getScheduler().scheduleSyncDelayedTask(Core.getInstance(), new Runnable() {

                            public void run() {
                                sender.sendMessage("§2§l* §aObsidianCore has successfully updated, please reload the plugin");
                            }
                        }, 60L);
                try {
                    FileDownload.dlFile("https://dl.dropbox.com/s/c9849g3ksex0z1p/ObsidianCore.jar", "plugins/ObsidianCore.jar");
                } catch (IOException e) {
                    sender.sendMessage("§4§l** §ObsidianCore was unable to be updated");
                    Bukkit.getScheduler().cancelTasks(Core.getInstance());
                }
            }

 

Lol. There is nothing wrong with the code. The error is from an invalid plugin.yml

 

@cwhit0814
Your plugin must contain a plugin.yml. Make sure you include the plugin.yml with all the necessarily lines (which can be found here.)

 

@Zombie_Striker @CeramicTitan It gets corrupted from dropbox because I have a plugin yml file in it thats not invalid when I test it before I use the file download.

 

@cwhit0814 It's a problem with your plugin (or how you are exporting the jar?). If it's a problem with Dropbox (which I doubt it is) then it doesn't belong in this section of the forums.

 

@cwhit0814 Your method for updating is a bit different from mine. Does that download code actually work? All I see is you opening an input stream. Normally I would have thought that you would open the input stream, read/write the bytes, and use a callback to tell when it's done.

 

@567legodude @cwhit0814
Not exactly to the problem, but I think one of the cleanest ways to deal with resources (implementing AutoClosable) is the try-with-resource statement introduced in Java 7. The current try finally try catch is just so much boilerplate code.

 

No.

Think carefully about this error cause. This is the zip decoder saying that it found an empty file. Your code never actually downloads the file, it just opens some stuff.

You need to actually do something with these if you want to download the file, it doesn't just magically do it. Also, you should be doing this asynchronously to the main thread, there's no reason to hang the server while this downloads.

 

I'm not sure if you can legally download anything to the user's computer.

 

@mcdorli

I'm not sure that there's anything illegal about it, per se.

 

Quoted from the bukkitdev rules.

 

That would just prevent the plugin from being approved on BukkitDev. But I think they would catch the permissions bypass for a single player before they would find the download location. Either way though, it looks like a private plugin since the welcome message is for a single server name.

 

@mcdorli That's for plugins on BukkitDev. You have to download BukkitDev plugins from specifically them. But your own personal plugins not on BD, you can do whatever you want.

 

@mythbusterma

I get that but what I don't understand is why it worked on 1.8 and not 1.9

 

@cwhit0814
This has nothing to do with thew server version. This has to do with how you are exporting the plugin.

 

@cwhit0814

The only problem is that that code has never, will never, nor does work. It just flat out does nothing. So I'm not sure why anyone is confused about this.


@Zombie_Striker

It has to do with his code doing nothing lol.

 

At least it stops the main thread for a few seconds.

 

@cwhit0814
There is a Files.copy method since Java 7 that takes an input stream. You might look into that. But I would highly recommend following the tips given above and learning some more Java / Debugging. I mean, if you would have spelled out loudly what the code does the flaw would be quite obvious.