Weird java.lang.ExceptionInInitializerError JSoup

In my newest Project I use JSoup to retrieve a Webpage, get all Elements with the class ".heads" and then save specific parts of it to a file. When I run it, I get this error:

java.lang.ExceptionInInitializerError
    at org.jsoup.nodes.Entities$EscapeMode.<clinit>(Entities.java:19) ~[?:?]
    at org.jsoup.nodes.Document$OutputSettings.<init>(Document.java:373) ~[?:?]
    at org.jsoup.nodes.Document.<init>(Document.java:18) ~[?:?]
    at org.jsoup.parser.TreeBuilder.initialiseParse(TreeBuilder.java:29) ~[?:?]
    at org.jsoup.parser.TreeBuilder.parse(TreeBuilder.java:42) ~[?:?]
    at org.jsoup.parser.HtmlTreeBuilder.parse(HtmlTreeBuilder.java:53) ~[?:?]
    at org.jsoup.parser.Parser.parseInput(Parser.java:30) ~[?:?]
    at org.jsoup.helper.DataUtil.parseByteData(DataUtil.java:94) ~[?:?]
    at org.jsoup.helper.HttpConnection$Response.parse(HttpConnection.java:603) ~[?:?]
    at org.jsoup.helper.HttpConnection.get(HttpConnection.java:195) ~[?:?]
    at de.zbs.advancedheads.main.AdvancedHeads.downloadDatabase(AdvancedHeads.java:48) ~[?:?]
    at de.zbs.advancedheads.main.AdvancedHeads.onEnable(AdvancedHeads.java:33) ~[?:?]
    at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:321) ~[spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:340) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:405) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugin(CraftServer.java:357) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.enablePlugins(CraftServer.java:317) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.reload(CraftServer.java:741) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.Bukkit.reload(Bukkit.java:535) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:25) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:141) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchCommand(CraftServer.java:641) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.dispatchServerCommand(CraftServer.java:627) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at net.minecraft.server.v1_8_R3.DedicatedServer.aO(DedicatedServer.java:412) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:375) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:653) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:556) [spigot-1.8.8-R0.1-SNAPSHOT-latest.jar:git-Spigot-fdc1440-53fac9f]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_73]
Caused by: java.lang.NullPointerException
    at java.util.Properties$LineReader.readLine(Unknown Source) ~[?:1.8.0_73]
    at java.util.Properties.load0(Unknown Source) ~[?:1.8.0_73]
    at java.util.Properties.load(Unknown Source) ~[?:1.8.0_73]
    at org.jsoup.nodes.Entities.loadEntities(Entities.java:236) ~[?:?]
    at org.jsoup.nodes.Entities.<clinit>(Entities.java:220) ~[?:?]
    ... 28 more

My Code is the following:

private boolean downloadDatabase() {
    new File(path).mkdirs();
    try {
        Document doc = Jsoup.connect("http://heads.freshcoal.com/maincollection.php").get();
        Elements head = doc.select(".heads");
        System.out.println(head);
        for (Element e : head) {
            Attributes att = e.attributes();
            System.out.println(att);
            String command = att.get("data-clipboard-text");
            System.out.println(command);
            String remover = command.replace("/give @p skull 1 3 {display:{Name:\"", "");
            String name = remover.substring(0, 5);
            Bukkit.broadcastMessage(name);
            String texture = remover.substring(30, 50);
            Bukkit.broadcastMessage(texture);
        }
        return true;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
}

Yes, I already checked wether the jsoup library is installed, I didn't know how to make it a library so I just took the sources of it and put it into my project.

Thanks for any help in advance!