Updates software version to 1.4.0

Fixes a potential NullPointerException
Adds a check to make sure the backup location has enough available space
Adds a message when calculating backup size to make it clear that the software is not frozen

README.md

@@ -1,6 +1,13 @@
 # Minecraft-Server-Launcher
-I originally created this software in 2013 using AutoIt. Since I am now learning Java, I have recreated it in Java.
+I originally created this software in 2013 using AutoIt. After learning Java, I recreated it in Java.
 The original version can be found at: https://archive.knarcraft.net/Scripts/BungeeMinecraftServerLauncher/
-Its goal is to do everything the original does, just better. The original is 1595 lines of code repetition and dirty code. I had no prior programming experience when I first started working on the original, which is why it became such a mess.
+This version's goal is to do everything the original does, just better. The original is 1595 lines of code repetition 
+and dirty code. I had no prior programming experience when I first started working on the original, which is why it 
+became such a mess.
 
-The code is now in a fully working state. It is still missing an auto update feature, but it can be used, and is fully functional.
+The software is in a fully working stage with a functional updater. The software is still in beta because there are still
+a lot of things I want to change and small annoyances. The software is fully portable. Make sure to put it in its own
+folder as it will create lots of files.
+
+The updater will move the new version to minecraft-server-launcher.jar, so you should rename the downloaded
+file to this if it's named something else to avoid confusion.

src/main/java/net/knarcraft/minecraftserverlauncher/Main.java

@@ -2,7 +2,7 @@ package net.knarcraft.minecraftserverlauncher;
 
 import net.knarcraft.minecraftserverlauncher.profile.Collection;
 import net.knarcraft.minecraftserverlauncher.profile.ServerLauncherController;
-import net.knarcraft.minecraftserverlauncher.server.Server;
+import net.knarcraft.minecraftserverlauncher.server.ServerHandler;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerConsoles;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerLauncherGUI;
 import net.knarcraft.minecraftserverlauncher.utility.CommonFunctions;
@@ -21,7 +21,7 @@ import java.util.concurrent.TimeUnit;
  * A software for managing Minecraft servers.
  *
  * @author Kristian Knarvik <kristian.knarvik@knett.no>
- * @version 1.0.0
+ * @version b1.3.4
  * @since 1.0.0
  */
 
@@ -34,8 +34,14 @@ public class Main {
     private static ServerLauncherGUI gui;
 
     public static void main(String[] args) throws IOException {
+        String logFile = Main.getApplicationWorkDirectory() + File.separator + "latestrun.log";
+        CommonFunctions.writeFile(logFile, "[Info]: Starting Minecraft Server Launcher v." +
+                Updater.getCurrentVersion()[1]);
+        try {
             Updater.checkForUpdate(updateURL, updateChannel);
-        CommonFunctions.writeFile(Main.getApplicationWorkDirectory() + File.separator + "latestrun.log", "");
+        } catch (IOException e) {
+            CommonFunctions.appendFile(logFile, "[Warning]: Unable to complete update procedure: " + e.getMessage());
+        }
         EventQueue.invokeLater(() -> {
             try {
                 ServerConsoles.instantiate();
@@ -82,7 +88,7 @@ public class Main {
         boolean runningNew = serversRunning();
         if (serversAreRunning && !runningNew) {
             //Servers stopped running
-            Server.serversStopped();
+            ServerHandler.serversStopped();
             gui.updateGUIElementsWhenServersStartOrStop(false);
             gui.setStatus("Servers are stopped");
         } else if (!serversAreRunning && runningNew) {

src/main/java/net/knarcraft/minecraftserverlauncher/profile/Profile.java

@@ -2,6 +2,7 @@ package net.knarcraft.minecraftserverlauncher.profile;
 
 import net.knarcraft.minecraftserverlauncher.Main;
 import net.knarcraft.minecraftserverlauncher.server.Server;
+import net.knarcraft.minecraftserverlauncher.server.ServerHandler;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerConsoles;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerLauncherGUI;
 import net.knarcraft.minecraftserverlauncher.utility.CommonFunctions;
@@ -10,6 +11,7 @@ import javax.naming.ConfigurationException;
 import javax.swing.*;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.List;
 
 /**
  * Keeps track of a set of servers and some user settings
@@ -21,7 +23,7 @@ import java.util.ArrayList;
 public class Profile {
 
     private static final ServerLauncherGUI serverLauncherGui = Main.getController().getGUI();
-    private final ArrayList<Collection> collections;
+    private final List<Collection> collections;
     private final String name;
     private boolean runInBackground;
     private int delayStartup;
@@ -105,7 +107,7 @@ public class Profile {
      *
      * @return <p>All collections stored by this profile</p>
      */
-    public ArrayList<Collection> getCollections() {
+    public List<Collection> getCollections() {
         return this.collections;
     }
 
@@ -239,10 +241,10 @@ public class Profile {
             if (data[1].contains("!")) {
                 String[] servers = data[1].split("!", -1);
                 for (String server : servers) {
-                    profile.collections.add(new Collection(Server.fromString(server)));
+                    profile.collections.add(new Collection(ServerHandler.fromString(server)));
                 }
             } else {
-                profile.collections.add(new Collection(Server.fromString(data[1])));
+                profile.collections.add(new Collection(ServerHandler.fromString(data[1])));
             }
         } else {
             profile = parseProfile(profileString.split(";", -1));

src/main/java/net/knarcraft/minecraftserverlauncher/profile/ServerLauncherController.java

@@ -2,6 +2,7 @@ package net.knarcraft.minecraftserverlauncher.profile;
 
 import net.knarcraft.minecraftserverlauncher.Main;
 import net.knarcraft.minecraftserverlauncher.server.Server;
+import net.knarcraft.minecraftserverlauncher.server.ServerHandler;
 import net.knarcraft.minecraftserverlauncher.server.ServerTypeHandler;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerLauncherGUI;
 import net.knarcraft.minecraftserverlauncher.userinterface.ServerTab;
@@ -392,7 +393,7 @@ public class ServerLauncherController {
             });
         }
         if (this.currentProfile.getRunInBackground()) {
-            Executors.newSingleThreadExecutor().execute(Server::startServers);
+            Executors.newSingleThreadExecutor().execute(ServerHandler::startServers);
             this.serverLauncherGUI.hideToTray();
         }
     }

src/main/java/net/knarcraft/minecraftserverlauncher/server/Server.java

@@ -1,9 +1,9 @@
 package net.knarcraft.minecraftserverlauncher.server;
 
 import net.knarcraft.minecraftserverlauncher.Main;
-import net.knarcraft.minecraftserverlauncher.profile.Collection;
 import net.knarcraft.minecraftserverlauncher.profile.ServerLauncherController;
 import net.knarcraft.minecraftserverlauncher.server.servertypes.ServerType;
+import net.knarcraft.minecraftserverlauncher.userinterface.ServerLauncherGUI;
 import net.knarcraft.minecraftserverlauncher.utility.CommonFunctions;
 
 import javax.naming.ConfigurationException;
@@ -31,14 +31,9 @@ import java.util.regex.Pattern;
  * @since 1.0.0
  */
 public class Server {
-    /**
-     * Available ram sizes. For ServerLauncherGUI combo
-     */
-    private static final String[] ramList = {"512M", "1G", "2G", "3G", "4G", "5G", "6G", "7G", "8G", "9G", "10G",
-            "11G", "12G", "13G", "14G", "15G", "16G"};
+
     private static final String jarDirectory = Main.getApplicationWorkDirectory() + File.separator + "files" +
             File.separator + "Jars" + File.separator;
-
     private final String name;
     private final ArrayList<String> playerList;
     private String path;
@@ -51,7 +46,7 @@ public class Server {
     private BufferedReader reader;
     private boolean started;
     private ScheduledExecutorService consoleOutputExecutor;
-    private static boolean stoppingServers = false;
+    private final ServerLauncherGUI gui = Main.getController().getGUI();
 
     /**
      * Initializes a new server with default values
@@ -65,7 +60,7 @@ public class Server {
         this.playerList = new ArrayList<>();
         this.type = null;
         this.serverVersion = "";
-        this.maxRam = ramList[0];
+        this.maxRam = ServerHandler.getRamList()[0];
         this.process = null;
         this.writer = null;
         this.reader = null;
@@ -91,15 +86,6 @@ public class Server {
         this.playerList = new ArrayList<>();
     }
 
-    /**
-     * Gets the list of available RAM choices allowed
-     *
-     * @return <p>All available RAM choices</p>
-     */
-    public static String[] getRamList() {
-        return ramList;
-    }
-
     /**
      * Gets the buffered reader used to read from this server
      *
@@ -109,101 +95,6 @@ public class Server {
         return this.reader;
     }
 
-    /**
-     * Marks the servers as finished stopping when a stop is confirmed
-     */
-    public static void serversStopped() {
-        if (stoppingServers) {
-            stoppingServers = false;
-        }
-    }
-
-    /**
-     * Tries to stop all enabled servers
-     *
-     * @throws IOException <p>If a writer's process is already closed but not null</p>
-     */
-    public static void stop() throws IOException, InterruptedException {
-        if (stoppingServers) {
-            killServers();
-            return;
-        }
-
-        stoppingServers = true;
-        for (Collection collection : Main.getController().getCurrentProfile().getCollections()) {
-            Server server = collection.getServer();
-            if (server.writer != null) {
-                if (server.type.isProxy()) {
-                    server.writer.write("end\n");
-                } else {
-                    server.writer.write("stop\n");
-                }
-                server.writer.flush();
-                server.writer = null;
-                server.started = false;
-            }
-        }
-    }
-
-    /**
-     * Kills all server processes
-     *
-     * @throws InterruptedException <p>If interrupted waiting for any of the servers to stop</p>
-     */
-    private static void killServers() throws InterruptedException {
-        for (Collection collection : Main.getController().getCurrentProfile().getCollections()) {
-            Server server = collection.getServer();
-            killServer(server);
-        }
-    }
-
-    /**
-     * Kills the given server after waiting 30 seconds for it to terminate normally
-     *
-     * @param server <p>The server to kill</p>
-     * @throws InterruptedException <p>If interrupted waiting for the server to stop</p>
-     */
-    private static void killServer(Server server) throws InterruptedException {
-        if (server.process != null) {
-            if (!server.process.waitFor(30, TimeUnit.SECONDS)) {
-                server.process.destroyForcibly();
-                server.process.waitFor();
-            }
-        }
-    }
-
-    /**
-     * Runs all enabled servers with their settings
-     */
-    public static void startServers() {
-        ServerLauncherController controller = Main.getController();
-        controller.getGUI().setStatus("Starting servers");
-        int serverNum = 0;
-        for (Collection collection : controller.getCurrentProfile().getCollections()) {
-            if (!collection.getServer().runServer(serverNum++ == 0)) {
-                controller.getGUI().showError("An error occurred. Start aborted. Please check the BuildTools log.");
-                try {
-                    Server.stop();
-                } catch (IOException | InterruptedException e) {
-                    e.printStackTrace();
-                }
-                controller.getGUI().updateGUIElementsWhenServersStartOrStop(false);
-                return;
-            }
-        }
-    }
-
-    /**
-     * Gets a server object from a server save string
-     *
-     * @param saveString <p>The string containing necessary data regarding the server</p>
-     * @return <p>A server in the same state it was saved in</p>
-     */
-    public static Server fromString(String saveString) throws ConfigurationException {
-        String[] data = saveString.split(";");
-        return new Server(data[0], data[1], Boolean.parseBoolean(data[2]), data[3], data[4], data[5]);
-    }
-
     /**
      * Gets the name of the server
      *
@@ -269,6 +160,42 @@ public class Server {
         }
     }
 
+    /**
+     * Gets whether this server is a proxy server
+     *
+     * <p>A proxy server is a server running BungeeCord, Waterfall or Travertine.</p>
+     *
+     * @return <p>True if this server is a proxy server</p>
+     */
+    public boolean isProxy() {
+        return this.type.isProxy();
+    }
+
+    /**
+     * Marks this server as stopped
+     */
+    public void setStopped() {
+        this.started = false;
+    }
+
+    /**
+     * Gets the writer used to write to this server
+     *
+     * @return <p>The writer used.</p>
+     */
+    public BufferedWriter getWriter() {
+        return this.writer;
+    }
+
+    /**
+     * Sets the writer used to write to this server
+     *
+     * @param writer <p>The new writer to use.</p>
+     */
+    public void setWriter(BufferedWriter writer) {
+        this.writer = writer;
+    }
+
     /**
      * Gets the path for this server's files
      *
@@ -374,7 +301,7 @@ public class Server {
      */
     private void addPlayer(String name) {
         this.playerList.add(name);
-        Main.getController().getGUI().getServerControlTab().addPlayer(name);
+        gui.getServerControlTab().addPlayer(name);
     }
 
     /**
@@ -384,7 +311,7 @@ public class Server {
      */
     private void removePlayer(String name) {
         playerList.removeIf(player -> player.equals(name));
-        Main.getController().getGUI().getServerControlTab().removePlayer(name);
+        gui.getServerControlTab().removePlayer(name);
     }
 
     /**
@@ -399,10 +326,12 @@ public class Server {
     /**
      * Runs a Minecraft server
      *
+     * @param skipDelay <p>Whether to skip the startup delay for this server</p>
      * @return <p>True if nothing went wrong</p>
      */
-    private boolean runServer(boolean isFirstServer) {
-        if (stoppingServers) {
+    public boolean runServer(boolean skipDelay) {
+        if (ServerHandler.stoppingServers()) {
+            gui.logMessage("Stopping servers. Cannot start yet.");
             return false;
         }
         //Ignore a disabled server
@@ -411,21 +340,23 @@ public class Server {
             return true;
         }
         //Tries to do necessary pre-start work
-        if (!initializeJarDownload() || (!isFirstServer && !delayStartup())) {
+        if (!initializeJarDownload() || (!skipDelay && !delayStartup())) {
+            gui.logError("Failed to perform startup tasks.");
             this.started = false;
             return false;
         }
-        if (stoppingServers) {
+        if (ServerHandler.stoppingServers()) {
+            gui.logMessage("Stopping servers. Cannot start yet.");
             return false;
         }
         //Starts the server if possible
         try {
             startServerProcess();
-            Main.getController().getGUI().setStatus("Servers are running");
+            gui.setStatus("Servers are running");
             this.started = true;
             return true;
         } catch (IOException e) {
-            Main.getController().getGUI().setStatus("Could not start server");
+            gui.setStatus("Could not start server");
             this.started = false;
             return false;
         }
@@ -438,14 +369,17 @@ public class Server {
      */
     private String getJavaCommand() {
         ServerLauncherController controller = ServerLauncherController.getInstance();
+
         if (serverVersion.toLowerCase().contains("latest")) {
             return controller.getJavaCommand();
-        } else if (serverVersion.contains(".") && serverVersion.split("\\.").length >= 2 &&
-                Integer.parseInt(serverVersion.split("\\.")[1]) >= 17) {
+        } else if (serverVersion.contains(".") && serverVersion.split("\\.").length >= 2) {
+            try {
+                if (Integer.parseInt(serverVersion.split("\\.")[1]) >= 17) {
                     return controller.getJavaCommand();
-        } else {
-            return controller.getOldJavaCommand();
                 }
+            } catch (NumberFormatException ignored) {}
+        }
+        return controller.getOldJavaCommand();
     }
 
     /**
@@ -529,11 +463,11 @@ public class Server {
     private String getPlayer(String text, boolean joined) {
         String playerName;
 
-        String loginPattern1 = " ([A-Z0-9a-z]+)\\[/[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+:[0-9]+] logged in";
-        String loginPattern2 = "UUID of player ([A-Z0-9a-z]+) is";
+        String loginPattern1 = " ([A-Z0-9a-z_]+)\\[/[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+:[0-9]+] logged in";
+        String loginPattern2 = "UUID of player ([A-Z0-9a-z_]+) is";
 
-        String logoutPattern1 = "INFO]: ([A-Z0-9a-z]+) lost connection";
-        String logoutPattern2 = " ([A-Z0-9a-z]+) left the game";
+        String logoutPattern1 = "INFO]: ([A-Z0-9a-z_]+) lost connection";
+        String logoutPattern2 = " ([A-Z0-9a-z_]+) left the game";
 
         if (joined) {
             playerName = getFirstRegexCaptureGroup(loginPattern1, text);
@@ -573,7 +507,7 @@ public class Server {
      */
     private boolean delayStartup() {
         try {
-            Main.getController().getGUI().setStatus("Delaying startup");
+            gui.setStatus("Delaying startup");
             TimeUnit.SECONDS.sleep(Main.getController().getCurrentProfile().getDelayStartup());
             return true;
         } catch (InterruptedException e) {
@@ -589,19 +523,16 @@ public class Server {
      * @return <p>True if nothing went wrong</p>
      */
     private boolean initializeJarDownload() {
-        ServerLauncherController controller = Main.getController();
-        if (!controller.getDownloadAllJars()) {
         try {
-                controller.getGUI().setStatus("Downloading jar...");
+            gui.setStatus("Downloading jar...");
             this.downloadJar();
-                controller.getGUI().setStatus("File downloaded");
+            gui.setStatus("File downloaded");
         } catch (IOException e) {
-                controller.getGUI().setStatus("Error: Jar file not found");
-                e.printStackTrace();
+            gui.setStatus("Error: Jar file could not be found, downloaded or built.");
+            gui.logError("Unable to get required .jar file: " + e.getMessage());
             this.started = false;
             return false;
         }
-        }
         return true;
     }
 

src/main/java/net/knarcraft/minecraftserverlauncher/server/ServerHandler.java

@@ -0,0 +1,151 @@
+package net.knarcraft.minecraftserverlauncher.server;
+
+import net.knarcraft.minecraftserverlauncher.Main;
+import net.knarcraft.minecraftserverlauncher.profile.Collection;
+import net.knarcraft.minecraftserverlauncher.profile.ServerLauncherController;
+import net.knarcraft.minecraftserverlauncher.userinterface.ServerLauncherGUI;
+
+import javax.naming.ConfigurationException;
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.util.concurrent.TimeUnit;
+
+public class ServerHandler {
+
+    /**
+     * Available ram sizes. For ServerLauncherGUI combo
+     */
+    private static final String[] ramList = {"512M", "1G", "2G", "3G", "4G", "5G", "6G", "7G", "8G", "9G", "10G",
+            "11G", "12G", "13G", "14G", "15G", "16G"};
+
+    private static boolean stoppingServers = false;
+    private static final ServerLauncherGUI gui = Main.getController().getGUI();
+
+    /**
+     * Gets the list of available RAM choices allowed
+     *
+     * @return <p>All available RAM choices</p>
+     */
+    public static String[] getRamList() {
+        return ramList;
+    }
+
+    /**
+     * Gets whether the servers are currently in the process of stopping
+     *
+     * @return <p>True if the servers are in the process of stopping.</p>
+     */
+    public static boolean stoppingServers() {
+        return stoppingServers;
+    }
+
+    /**
+     * Marks the servers as finished stopping when a stop is confirmed
+     */
+    public static void serversStopped() {
+        if (stoppingServers) {
+            stoppingServers = false;
+        }
+    }
+
+    /**
+     * Tries to stop all enabled servers
+     *
+     * @throws IOException <p>If a writer's process is already closed but not null</p>
+     */
+    public static void stop() throws IOException, InterruptedException {
+        if (stoppingServers) {
+            killServers();
+            return;
+        }
+
+        stoppingServers = true;
+        int serversRunning = 0;
+
+        for (Collection collection : Main.getController().getCurrentProfile().getCollections()) {
+            Server server = collection.getServer();
+            BufferedWriter writer = server.getWriter();
+            if (writer != null) {
+                serversRunning++;
+                if (server.isProxy()) {
+                    writer.write("end\n");
+                } else {
+                    writer.write("stop\n");
+                }
+                writer.flush();
+                server.setWriter(null);
+                server.setStopped();
+            }
+        }
+
+        if (serversRunning == 0) {
+            stoppingServers = false;
+        }
+    }
+
+    /**
+     * Kills all server processes
+     *
+     * @throws InterruptedException <p>If interrupted waiting for any of the servers to stop</p>
+     */
+    private static void killServers() throws InterruptedException {
+        for (Collection collection : Main.getController().getCurrentProfile().getCollections()) {
+            Server server = collection.getServer();
+            killServer(server);
+        }
+    }
+
+    /**
+     * Kills the given server after waiting 30 seconds for it to terminate normally
+     *
+     * @param server <p>The server to kill</p>
+     * @throws InterruptedException <p>If interrupted waiting for the server to stop</p>
+     */
+    private static void killServer(Server server) throws InterruptedException {
+        Process serverProcess = server.getProcess();
+        if (serverProcess != null) {
+            if (!serverProcess.waitFor(30, TimeUnit.SECONDS)) {
+                serverProcess.destroyForcibly();
+                serverProcess.waitFor();
+            }
+        }
+    }
+
+    /**
+     * Runs all enabled servers with their settings
+     */
+    public static void startServers() {
+        ServerLauncherController controller = Main.getController();
+        gui.setStatus("Starting servers");
+        Server previouslyStartedServer = null;
+
+        for (Collection collection : controller.getCurrentProfile().getCollections()) {
+            Server server = collection.getServer();
+            if (!server.runServer(previouslyStartedServer == null || previouslyStartedServer.isProxy())) {
+                gui.showError("An error occurred. Start aborted. Please check relevant log files.");
+                try {
+                    stop();
+                } catch (IOException | InterruptedException e) {
+                    e.printStackTrace();
+                }
+                gui.updateGUIElementsWhenServersStartOrStop(false);
+                return;
+            }
+            if (server.isEnabled()) {
+                previouslyStartedServer = server;
+            }
+        }
+    }
+
+    /**
+     * Gets a server object from a server save string
+     *
+     * @param saveString <p>The string containing necessary data regarding the server</p>
+     * @return <p>A server in the same state it was saved in</p>
+     */
+    public static Server fromString(String saveString) throws ConfigurationException {
+        String[] data = saveString.split(";");
+        return new Server(data[0], data[1], Boolean.parseBoolean(data[2]), data[3], data[4], data[5]);
+    }
+
+}

src/main/java/net/knarcraft/minecraftserverlauncher/server/ServerTypeHandler.java

@@ -134,7 +134,7 @@ public class ServerTypeHandler {
                 break;
             case "Paper":
                 newType = new Paper("Paper", false, serverVersions, serverTypeInfo[2],
-                        serverTypeInfo[3]);
+                        serverTypeInfo[3], serverTypeInfo[4], serverTypeInfo[5]);
                 break;
             case "Bungee":
                 newType = new BungeeCord("Bungee", true, serverVersions, serverTypeInfo[2],

src/main/java/net/knarcraft/minecraftserverlauncher/server/ServerVersionContainer.java

@@ -22,6 +22,7 @@ public class ServerVersionContainer {
     private String bungeeVersion;
     private Map<String, String> waterfallVersions;
     private Map<String, String> travertineVersions;
+    private Map<String, String> paperVersions;
     private Map<String, String> spongeVanillaVersions;
     private Map<String, String> spongeForgeVersions;
     private String downloadedBuildToolsVersion;
@@ -32,6 +33,7 @@ public class ServerVersionContainer {
     private ServerVersionContainer() {
         this.waterfallVersions = new HashMap<>();
         this.travertineVersions = new HashMap<>();
+        this.paperVersions = new HashMap<>();
         this.spongeVanillaVersions = new HashMap<>();
         this.spongeForgeVersions = new HashMap<>();
         loadState();
@@ -58,6 +60,7 @@ public class ServerVersionContainer {
         this.bungeeVersion = null;
         this.waterfallVersions = new HashMap<>();
         this.travertineVersions = new HashMap<>();
+        this.paperVersions = new HashMap<>();
         this.spongeVanillaVersions = new HashMap<>();
         this.spongeForgeVersions = new HashMap<>();
         this.downloadedBuildToolsVersion = null;
@@ -70,6 +73,7 @@ public class ServerVersionContainer {
                 "bungeeVersion;" + bungeeVersion + "\n" +
                 "waterfallVersions;" + mapToString(waterfallVersions) + "\n" +
                 "travertineVersions;" + mapToString(travertineVersions) + "\n" +
+                "paperVersions;" + mapToString(paperVersions) + "\n" +
                 "spongeVanillaVersions;" + mapToString(spongeVanillaVersions) + "\n" +
                 "spongeForgeVersions;" + mapToString(spongeForgeVersions) + "\n" +
                 "downloadedBuildToolsVersion;" + downloadedBuildToolsVersion;
@@ -163,6 +167,9 @@ public class ServerVersionContainer {
             case "travertineVersions":
                 parseVersionsToMap(travertineVersions, variableValue);
                 break;
+            case "paperVersions":
+                parseVersionsToMap(paperVersions, variableValue);
+                break;
             case "spongeVanillaVersions":
                 parseVersionsToMap(spongeVanillaVersions, variableValue);
                 break;
@@ -291,6 +298,27 @@ public class ServerVersionContainer {
         saveState();
     }
 
+    /**
+     * Gets a specific paper version
+     *
+     * @param versionKey <p>The version to check the current version of</p>
+     * @return <p>The current paper version</p>
+     */
+    public String getPaperVersion(String versionKey) {
+        return this.paperVersions.get(versionKey);
+    }
+
+    /**
+     * Sets the current version for a given paper version
+     *
+     * @param mapKey <p>The version key to set version for</p>
+     * @param newValue <p>The new current version</p>
+     */
+    public void setPaperVersion(String mapKey, String newValue) {
+        this.paperVersions.put(mapKey, newValue);
+        saveState();
+    }
+
     /**
      * Gets a specific sponge vanilla version
      *

src/main/java/net/knarcraft/minecraftserverlauncher/server/servertypes/Paper.java

@@ -3,19 +3,25 @@ package net.knarcraft.minecraftserverlauncher.server.servertypes;
 /**
  * This class represents the Paper Minecraft server type
  */
-public class Paper extends Spigot {
+public class Paper extends Waterfall {
 
     /**
      * Instantiates a new Paper server type
      *
      * @param typeName    <p>The name of the server type</p>
      * @param isProxy     <p>Whether this server type is a proxy server</p>
-     * @param versions        <p>A list of one or more server versions for the type</p>
-     * @param downloadURL     <p>The URL used for downloading .jar files</p>
-     * @param downloadURLPart <p>A string used after the download url as an additional part of the URL</p>
+     * @param versions    <p>The available versions for the server type</p>
+     * @param versionURL  <p>The URL used to finding the newest version</p>
+     * @param srcStart    <p>The string after which the version id starts</p>
+     * @param srcEnd      <p>The string marking the end of the version id</p>
+     * @param downloadURL <p>The URL used for downloading the latest version</p>
      */
-    public Paper(String typeName, boolean isProxy, String[] versions, String downloadURL, String downloadURLPart) {
-        super(typeName, isProxy, versions, downloadURL, downloadURLPart);
+    public Paper(String typeName, boolean isProxy, String[] versions, String versionURL, String srcStart,
+                 String srcEnd, String downloadURL) {
+        super(typeName, isProxy, versions, versionURL, srcStart, srcEnd, downloadURL);
+
+        this.oldVersionFunction = serverVersionContainer::getPaperVersion;
+        this.versionUpdateFunction = serverVersionContainer::setPaperVersion;
     }
 
 }

src/main/java/net/knarcraft/minecraftserverlauncher/userinterface/BackupGUI.java

@@ -0,0 +1,95 @@
+package net.knarcraft.minecraftserverlauncher.userinterface;
+
+import net.knarcraft.minecraftserverlauncher.utility.BackupUtil;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+/**
+ * The Backup GUI is used to display backup progress
+ */
+public class BackupGUI implements ActionListener {
+    private static JFrame frame;
+    private static JTextArea progressTextArea;
+    private static JProgressBar progressBar;
+    private static JButton cancelButton;
+
+    /**
+     * Instantiates a new GUI
+     */
+    public BackupGUI() {
+        instantiate();
+    }
+
+    /**
+     * Initializes the server consoles frame
+     */
+    public void instantiate() {
+        if (frame != null) {
+            return;
+        }
+        frame = new JFrame("Running backup...");
+        frame.setBounds(100, 100, 500, 140);
+        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
+        progressTextArea = new JTextArea();
+        progressTextArea.setEditable(false);
+        progressBar = new JProgressBar();
+        cancelButton = new JButton("Cancel");
+        JPanel panel = new JPanel();
+        panel.setLayout(new BoxLayout(panel, BoxLayout.PAGE_AXIS));
+        panel.add(progressTextArea);
+        panel.add(Box.createRigidArea(new Dimension(0,5)));
+        panel.add(progressBar);
+
+        JPanel buttonPane = new JPanel();
+        buttonPane.setLayout(new BoxLayout(buttonPane, BoxLayout.LINE_AXIS));
+        buttonPane.setBorder(BorderFactory.createEmptyBorder(0, 10, 10, 10));
+        buttonPane.add(Box.createHorizontalGlue());
+        buttonPane.add(cancelButton);
+        cancelButton.addActionListener(BackupGUI.this);
+
+        panel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
+        Container contentPane = frame.getContentPane();
+        contentPane.add(panel, BorderLayout.CENTER);
+        contentPane.add(buttonPane, BorderLayout.PAGE_END);
+        frame.setVisible(true);
+    }
+
+    /**
+     * Updates information about the backup progress
+     *
+     * @param infoText <p>The text to display</p>
+     * @param progressPercent <p>The new percent of the progress bar</p>
+     */
+    public static void updateProgress(String infoText, int progressPercent) {
+        if (progressTextArea != null) {
+            progressTextArea.setText(infoText);
+        }
+        if (progressBar != null) {
+            progressBar.setValue(progressPercent);
+        }
+    }
+
+    /**
+     * Destroys the backup GUI
+     */
+    public static void destroy() {
+        if (frame != null) {
+            frame.dispose();
+            frame = null;
+            progressBar = null;
+            progressTextArea = null;
+            cancelButton = null;
+        }
+    }
+
+    @Override
+    public void actionPerformed(ActionEvent actionEvent) {
+        if (actionEvent.getSource() == cancelButton) {
+            BackupUtil.abortBackup();
+            destroy();
+        }
+    }
+}

src/main/java/net/knarcraft/minecraftserverlauncher/userinterface/Console.java

@@ -93,7 +93,7 @@ public class Console extends KeyAdapter implements ActionListener, KeyListener {
         StringBuilder newTextBuilder = new StringBuilder();
         for (String line : oldTextList) {
             if (!line.equals("")) {
-                newTextBuilder.append(line);
+                newTextBuilder.append(line).append("\n");
             }
         }
         this.textOutput.setText(newTextBuilder.toString());

src/main/java/net/knarcraft/minecraftserverlauncher/userinterface/ServerLauncherGUI.java

@@ -3,8 +3,8 @@ package net.knarcraft.minecraftserverlauncher.userinterface;
 import net.knarcraft.minecraftserverlauncher.Main;
 import net.knarcraft.minecraftserverlauncher.profile.Collection;
 import net.knarcraft.minecraftserverlauncher.profile.ServerLauncherController;
-import net.knarcraft.minecraftserverlauncher.server.Server;
-import net.knarcraft.minecraftserverlauncher.utility.CommonFunctions;
+import net.knarcraft.minecraftserverlauncher.server.ServerHandler;
+import net.knarcraft.minecraftserverlauncher.utility.BackupUtil;
 
 import javax.imageio.ImageIO;
 import javax.naming.ConfigurationException;
@@ -33,7 +33,7 @@ import static net.knarcraft.minecraftserverlauncher.utility.CommonFunctions.getR
  */
 public class ServerLauncherGUI extends MessageHandler implements ActionListener, GUI {
 
-    private final JLabel lblStatuslabel = new JLabel("Servers are stopped");
+    private final JLabel lblStatusLabel = new JLabel("Servers are stopped");
     private final ServerLauncherController controller;
     private Map<String, String> textStrings;
     private Tray applicationTray;
@@ -101,7 +101,7 @@ public class ServerLauncherGUI extends MessageHandler implements ActionListener,
 
     @Override
     public void setStatus(String text) {
-        this.lblStatuslabel.setText(text);
+        this.lblStatusLabel.setText(text);
         this.logMessage(text);
     }
 
@@ -243,11 +243,11 @@ public class ServerLauncherGUI extends MessageHandler implements ActionListener,
         panelBasic.add(profiles);
         profiles.addActionListener(this);
 
-        sl_panel.putConstraint(SpringLayout.NORTH, lblStatuslabel, 6, SpringLayout.SOUTH, addProfileButton);
-        sl_panel.putConstraint(SpringLayout.SOUTH, lblStatuslabel, -10, SpringLayout.SOUTH, panelBasic);
-        sl_panel.putConstraint(SpringLayout.WEST, lblStatuslabel, 10, SpringLayout.WEST, panelBasic);
-        sl_panel.putConstraint(SpringLayout.EAST, lblStatuslabel, -10, SpringLayout.EAST, panelBasic);
-        panelBasic.add(lblStatuslabel);
+        sl_panel.putConstraint(SpringLayout.NORTH, lblStatusLabel, 6, SpringLayout.SOUTH, addProfileButton);
+        sl_panel.putConstraint(SpringLayout.SOUTH, lblStatusLabel, -10, SpringLayout.SOUTH, panelBasic);
+        sl_panel.putConstraint(SpringLayout.WEST, lblStatusLabel, 10, SpringLayout.WEST, panelBasic);
+        sl_panel.putConstraint(SpringLayout.EAST, lblStatusLabel, -10, SpringLayout.EAST, panelBasic);
+        panelBasic.add(lblStatusLabel);
 
         addServerButton = new JButton("Add server");
         sl_panel.putConstraint(SpringLayout.NORTH, addServerButton, 0, SpringLayout.NORTH, startServerButton);
@@ -314,7 +314,7 @@ public class ServerLauncherGUI extends MessageHandler implements ActionListener,
     @Override
     public void actionPerformed(ActionEvent e) {
         Object actionSource = e.getSource();
-        //Registers actions on the main tab
+        //Register actions on the main tab
         handleMainTabButtons(actionSource);
     }
 
@@ -327,13 +327,14 @@ public class ServerLauncherGUI extends MessageHandler implements ActionListener,
     private void handleMainTabButtons(Object actionSource) {
         if (actionSource == startServerButton) {
             controller.saveState();
-            Executors.newSingleThreadExecutor().execute(Server::startServers);
+            Executors.newSingleThreadExecutor().execute(ServerHandler::startServers);
         } else if (actionSource == stopServerButton) {
             stopServers();
         } else if (actionSource == addServerButton) {
             addServer();
         } else if (actionSource == backupButton) {
-            CommonFunctions.backup(this);
+            //Run backup in its own thread to prevent locking up
+            Executors.newSingleThreadExecutor().execute(() -> BackupUtil.backup(this));
         } else if (actionSource == addProfileButton) {
             controller.addProfile(JOptionPane.showInputDialog("Profile name: "));
             updateProfiles();
@@ -404,7 +405,7 @@ public class ServerLauncherGUI extends MessageHandler implements ActionListener,
     public void stopServers() {
         try {
             setStatus("Servers are stopping...");
-            Server.stop();
+            ServerHandler.stop();
         } catch (IOException e1) {
             showError("Could not stop server.");
             e1.printStackTrace();

src/main/java/net/knarcraft/minecraftserverlauncher/userinterface/ServerTab.java

@@ -1,7 +1,7 @@
 package net.knarcraft.minecraftserverlauncher.userinterface;
 
 import net.knarcraft.minecraftserverlauncher.Main;
-import net.knarcraft.minecraftserverlauncher.server.Server;
+import net.knarcraft.minecraftserverlauncher.server.ServerHandler;
 import net.knarcraft.minecraftserverlauncher.server.ServerTypeHandler;
 import net.knarcraft.minecraftserverlauncher.server.servertypes.ServerType;
 
@@ -76,7 +76,7 @@ public class ServerTab implements ActionListener {
         sl_panel_3.putConstraint(SpringLayout.WEST, lblMaxRam, 6, SpringLayout.EAST, serverTypes);
         panel.add(lblMaxRam);
 
-        maxRam = new JComboBox<>(Server.getRamList());
+        maxRam = new JComboBox<>(ServerHandler.getRamList());
         sl_panel_3.putConstraint(SpringLayout.NORTH, maxRam, 0, SpringLayout.NORTH, serverTypes);
         sl_panel_3.putConstraint(SpringLayout.WEST, maxRam, 6, SpringLayout.EAST, lblMaxRam);
         sl_panel_3.putConstraint(SpringLayout.EAST, maxRam, -10, SpringLayout.EAST, panel);

src/main/java/net/knarcraft/minecraftserverlauncher/utility/BackupUtil.java

@@ -0,0 +1,264 @@
+package net.knarcraft.minecraftserverlauncher.utility;
+
+import net.knarcraft.minecraftserverlauncher.Main;
+import net.knarcraft.minecraftserverlauncher.profile.Collection;
+import net.knarcraft.minecraftserverlauncher.server.Server;
+import net.knarcraft.minecraftserverlauncher.userinterface.BackupGUI;
+import net.knarcraft.minecraftserverlauncher.userinterface.GUI;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Stream;
+
+/**
+ * A helper class for performing server backup
+ */
+public class BackupUtil {
+
+    private static boolean backupAborted;
+    private static boolean backupRunning = false;
+
+    /**
+     * Aborts the currently running backup
+     */
+    public static void abortBackup() {
+        backupAborted = true;
+    }
+
+    /**
+     * Recursively copies a folder to another location
+     *
+     * @param source         <p>The folder to copy</p>
+     * @param destination    <p>Target destination</p>
+     * @param backupFileSize <p>The total file size of the backup in progress</p>
+     * @param alreadyCopied  <p>The amount of bytes already copied</p>
+     * @throws IOException <p>If we can't start a file stream</p>
+     */
+    private static long backupFolder(File source, File destination, long backupFileSize,
+                                                  long alreadyCopied) throws IOException {
+        if (backupAborted) {
+            return 0L;
+        }
+        if (!source.isDirectory()) {
+            long copiedFileSize = copyFile(source, destination);
+            BackupGUI.updateProgress("Copying " + source + "\n to " + destination,
+                    (int) ((alreadyCopied + copiedFileSize) * 100 / backupFileSize));
+            return copiedFileSize;
+        } else {
+            if (!destination.exists() && !destination.mkdir()) {
+                return 0L;
+            }
+            String[] files = source.list();
+            long copiedFilesSize = 0;
+            if (files != null) {
+                for (String file : files) {
+                    File srcFile = new File(source, file);
+                    File destinationFile = new File(destination, file);
+                    copiedFilesSize += backupFolder(srcFile, destinationFile, backupFileSize,
+                            alreadyCopied + copiedFilesSize);
+                    BackupGUI.updateProgress("Copying " + source + "\n to " + destination,
+                            (int) ((alreadyCopied + copiedFilesSize) * 100 / backupFileSize));
+                }
+            }
+            return copiedFilesSize;
+        }
+    }
+
+    /**
+     * Copies a file from one location to another
+     *
+     * @param source      <p>The file to copy</p>
+     * @param destination <p>The location of the copied file</p>
+     * @throws IOException <p>If reading or writing fails</p>
+     */
+    private static long copyFile(File source, File destination) throws IOException {
+        InputStream in = new FileInputStream(source);
+        OutputStream out = new FileOutputStream(destination);
+        byte[] buffer = new byte[1024];
+        int length;
+        while ((length = in.read(buffer)) > 0) {
+            out.write(buffer, 0, length);
+        }
+        in.close();
+        out.close();
+        return Files.size(source.toPath());
+    }
+
+    /**
+     * Copies all server directories to a folder specified by the user
+     *
+     * @param gui <p>The GUI to use for informing the user</p>
+     */
+    public static void backup(GUI gui) {
+        backupAborted = false;
+        if (backupRunning) {
+            gui.setStatus("A backup is already running");
+            return;
+        } else {
+            backupRunning = true;
+        }
+
+        //Get the folder to save the backed up files in
+        File path = gui.askForDirectory("Backup folder");
+        if (path == null || !path.isDirectory()) {
+            backupRunning = false;
+            return;
+        }
+
+        gui.setStatus("Backup running...");
+        List<List<File>> serverFolders = getFoldersOfEnabledServers(path);
+
+        gui.setStatus("Calculating backup size...");
+        long backupFileSize = getFolderSize(gui, serverFolders);
+
+        long locationFreeSpace = path.getFreeSpace();
+        if (locationFreeSpace < (backupFileSize + 2048000000)) {
+            gui.setStatus("Not enough available space. " + (backupFileSize / 1000000) + "MB necessary, but only " +
+                    (locationFreeSpace / 1000000) + "MB available");
+            backupRunning = false;
+            backupAborted = true;
+            return;
+        }
+
+        gui.setStatus("Backing up " + (backupFileSize / 1000000) + "MB");
+
+        performBackup(gui, serverFolders, backupFileSize);
+    }
+
+    /**
+     * Performs the actual backup after checks have passed and necessary info is available
+     * @param gui <p>The GUI to use for informing the user</p>
+     * @param serverFolders <p>The folders of the servers to backup</p>
+     * @param backupFileSize <p>The total size of the folders to backup</p>
+     */
+    private static void performBackup(GUI gui, List<List<File>> serverFolders, long backupFileSize) {
+        new BackupGUI();
+        BackupGUI.updateProgress("Backup starting...", 0);
+        long alreadyCopied = 0;
+        for (List<File> serverFolder : serverFolders) {
+            if (backupAborted || !backupRunning) {
+                gui.setStatus("Backup aborted");
+                backupRunning = false;
+                return;
+            }
+            alreadyCopied = backupServerFiles(gui, serverFolder, backupFileSize, alreadyCopied);
+        }
+        backupRunning = false;
+        if (backupAborted) {
+            gui.setStatus("Backup aborted");
+        } else {
+            BackupGUI.destroy();
+            gui.setStatus("Backup finished");
+        }
+    }
+
+    /**
+     * Backs up the files for a single server
+     *
+     * @param gui <p>The GUI to use for informing the user</p>
+     * @param serverFolder <p>The server's input and output folders</p>
+     * @param backupFileSize <p>The total size of the files to backup</p>
+     * @param alreadyCopied <p>The amount of bytes already copied</p>
+     * @return <p>The new amount of bytes copied</p>
+     */
+    private static long backupServerFiles(GUI gui, List<File> serverFolder, long backupFileSize, long alreadyCopied) {
+        File srcFolder = serverFolder.get(0);
+        File destinationFolder = serverFolder.get(1);
+
+        //Create child folders
+        if (!destinationFolder.exists() && !destinationFolder.mkdirs()) {
+            backupRunning = false;
+            gui.logError("Unable to create necessary sub-folder in the backup folder");
+            throw new IllegalArgumentException("Unable to create necessary sub-folder in the backup folder");
+        }
+        //Backup
+        try {
+            alreadyCopied += backupFolder(srcFolder, destinationFolder, backupFileSize, alreadyCopied);
+        } catch (IOException e) {
+            gui.showError("Backup caused an error: " + e.getMessage());
+            gui.logError(Arrays.toString(e.getStackTrace()));
+            BackupGUI.destroy();
+            backupRunning = false;
+        }
+        return alreadyCopied;
+    }
+
+    /**
+     * Gets the size of a list of folders
+     *
+     * @param gui           <p>The GUI to write any errors to</p>
+     * @param serverFolders <p>The folder to find the size of</p>
+     * @return <p>The size of the given folders</p>
+     */
+    private static long getFolderSize(GUI gui, List<List<File>> serverFolders) {
+        long folderSize = 0;
+        for (List<File> serverFolder : serverFolders) {
+            File srcFolder = serverFolder.get(0);
+            try (Stream<Path> walk = Files.walk(srcFolder.toPath())) {
+                folderSize += walk.filter(Files::isRegularFile).mapToLong(BackupUtil::getFileSize).sum();
+            } catch (IOException e) {
+                gui.setStatus(String.format("IO errors %s", e));
+            }
+        }
+        return folderSize;
+    }
+
+    /**
+     * Gets the input and output folders for enabled servers
+     *
+     * <p>The input folders are the folders to copy, while the output folders are the folders to write the backup to.
+     * Each list element contains a list of exactly two File items. The first one is the input folder, and the second
+     * one is the output folder</p>
+     *
+     * @param path <p>The path of the backup folder, as given by the user</p>
+     * @return <p>The folders to copy from/to</p>
+     */
+    private static List<List<File>> getFoldersOfEnabledServers(File path) {
+        List<List<File>> serverFolders = new ArrayList<>();
+
+        //Get folders of servers to back up
+        List<Collection> collections = Main.getController().getCurrentProfile().getCollections();
+        for (Collection collection : collections) {
+            //Ignore disabled and invalid servers
+            if (collection.getServer().getPath().equals("") || !collection.getServer().isEnabled()) {
+                continue;
+            }
+            //Decide sub-folders
+            Server targetServer = collection.getServer();
+            String name = targetServer.getName();
+            File srcFolder = new File(targetServer.getPath());
+            File destinationFolder = new File(path, name);
+
+            List<File> serverFolder = new ArrayList<>();
+            serverFolder.add(srcFolder);
+            serverFolder.add(destinationFolder);
+            serverFolders.add(serverFolder);
+        }
+        return serverFolders;
+    }
+
+    /**
+     * Gets the size of a file given its path
+     *
+     * @param path <p>The path to a file</p>
+     * @return <p>The size of the file in bytes, or 0 if an exception is thrown</p>
+     */
+    private static long getFileSize(Path path) {
+        try {
+            return Files.size(path);
+        } catch (IOException exception) {
+            System.out.printf("Failed to get size of %s%n%s", path, exception);
+            return 0L;
+        }
+    }
+
+}

src/main/java/net/knarcraft/minecraftserverlauncher/utility/CommonFunctions.java

@@ -1,9 +1,6 @@
 package net.knarcraft.minecraftserverlauncher.utility;
 
 import net.knarcraft.minecraftserverlauncher.Main;
-import net.knarcraft.minecraftserverlauncher.profile.Collection;
-import net.knarcraft.minecraftserverlauncher.server.Server;
-import net.knarcraft.minecraftserverlauncher.userinterface.GUI;
 import net.knarcraft.minecraftserverlauncher.userinterface.WebBrowser;
 
 import java.io.BufferedReader;
@@ -16,7 +13,6 @@ import java.io.FileWriter;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.net.URI;
 import java.net.URISyntaxException;
@@ -53,7 +49,7 @@ public final class CommonFunctions {
      * @param folder <p>The folder to create</p>
      * @throws FileNotFoundException <p>If unable to create the folder</p>
      */
-    protected static void createFolder(File folder) throws FileNotFoundException {
+    public static void createFolder(File folder) throws FileNotFoundException {
         if (!folder.exists()) {
             if (!folder.mkdirs()) {
                 throw new FileNotFoundException("Cannot create necessary directory.");
@@ -158,7 +154,7 @@ public final class CommonFunctions {
      * @throws IOException <p>If unable to write to the file</p>
      */
     public static void writeFile(String path, String text) throws IOException {
-        writeFile(path, text, true);
+        writeFile(path, text, !text.equals(""));
     }
 
     /**
@@ -210,55 +206,6 @@ public final class CommonFunctions {
         }
     }
 
-    /**
-     * Recursively copies a folder to another location
-     *
-     * @param source      <p>The folder to copy</p>
-     * @param destination <p>Target destination</p>
-     * @throws IOException <p>If we can't start a file stream</p>
-     */
-    private static void copyFolder(GUI serverLauncherGui, File source, File destination) throws IOException {
-        if (!source.isDirectory()) {
-            copyFile(serverLauncherGui, source, destination);
-        } else {
-            serverLauncherGui.setStatus("Copying directory " + source);
-            if (!destination.exists() && !destination.mkdir()) {
-                return;
-            }
-            String[] files = source.list();
-            if (files != null) {
-                for (String file : files) {
-                    File srcFile = new File(source, file);
-                    File destinationFile = new File(destination, file);
-                    copyFolder(serverLauncherGui, srcFile, destinationFile);
-                }
-            }
-            serverLauncherGui.setStatus("Copied directory " + source);
-        }
-    }
-
-    /**
-     * Copies a file from one location to another
-     *
-     * @param serverLauncherGui <p>The serverLauncherGui to use for alerting the user</p>
-     * @param source            <p>The file to copy</p>
-     * @param destination       <p>The location of the copied file</p>
-     * @throws IOException <p>If reading or writing fails</p>
-     */
-    private static void copyFile(GUI serverLauncherGui, File source, File destination) throws IOException {
-        serverLauncherGui.setStatus("Copying file " + source + "...");
-        InputStream in = new FileInputStream(source);
-        OutputStream out = new FileOutputStream(destination);
-        byte[] buffer = new byte[1024];
-        int length;
-        while ((length = in.read(buffer)) > 0) {
-            out.write(buffer, 0, length);
-        }
-        in.close();
-        out.close();
-        serverLauncherGui.setStatus("Copied file " + source);
-    }
-
     /**
      * Opens an url in the user's default application.
      *
@@ -295,34 +242,7 @@ public final class CommonFunctions {
         return text.toString().trim();
     }
 
-    /**
-     * Copies all server directories to a folder specified by the user.
-     */
-    public static void backup(GUI gui) {
-        File path = gui.askForDirectory("Backup folder");
-        for (Collection collection : Main.getController().getCurrentProfile().getCollections()) {
-            //Ignore disabled and invalid servers
-            if (collection.getServer().getPath().equals("") || !collection.getServer().isEnabled()) {
-                continue;
-            }
-            //Decide sub-folders
-            Server targetServer = collection.getServer();
-            String name = targetServer.getName();
-            File srcFolder = new File(targetServer.getPath());
-            File destinationFolder = new File(path, name);
-            //Create child folders
-            if (!destinationFolder.exists() && !destinationFolder.mkdirs()) {
-                throw new IllegalArgumentException("Unable to create necessary sub-folder in the backup folder");
-            }
-            //Backup
-            try {
-                CommonFunctions.copyFolder(gui, srcFolder, destinationFolder);
-            } catch (IOException e) {
-                e.printStackTrace();
-            }
-        }
-        gui.setStatus("Backup finished");
-    }
+
 
     /**
      * Validates that a name is not empty and does not contain invalid characters
@@ -331,7 +251,7 @@ public final class CommonFunctions {
      * @return <p>True if the name is valid</p>
      */
     public static boolean nameIsValid(String name) {
-        return !name.equals("") && name.matches("[^!?;,]+");
+        return name != null && !name.equals("") && name.matches("[^!?;,]+");
     }
 
     /**

src/main/java/net/knarcraft/minecraftserverlauncher/utility/Updater.java

@@ -29,13 +29,12 @@ public final class Updater {
     private static final String targetFile = "minecraft-server-launcher.jar";
 
     /**
-     * Checks if a newer version is available
+     * Gets the version channel and version of this software instance
      *
-     * @param updateURL     <p>The URL used for checking for updates</p>
-     * @param updateChannel <p>The release channel to use</p>
-     * @throws IOException <p>If the update data cannot be read</p>
+     * @return <p>An array of Channel, Version</p>
+     * @throws FileNotFoundException <p>If unable to find or read currentversion.csv</p>
      */
-    public static void checkForUpdate(String updateURL, String updateChannel) throws IOException {
+    public static String[] getCurrentVersion() throws FileNotFoundException {
         Scanner file = getResourceAsScanner("currentversion.csv");
         if (!file.hasNextLine()) {
             throw new FileNotFoundException("File currentversion.csv is invalid");
@@ -46,6 +45,20 @@ public final class Updater {
         }
         String oldVer = file.nextLine();
         file.close();
+        return new String[]{oldType, oldVer};
+    }
+
+    /**
+     * Checks if a newer version is available
+     *
+     * @param updateURL     <p>The URL used for checking for updates</p>
+     * @param updateChannel <p>The release channel to use</p>
+     * @throws IOException <p>If the update data cannot be read</p>
+     */
+    public static void checkForUpdate(String updateURL, String updateChannel) throws IOException {
+        String[] oldData = getCurrentVersion();
+        String oldType = oldData[0];
+        String oldVer = oldData[1];
 
         String data = readRemoteFile(updateURL);
         JsonObject jsonObject = new JsonParser().parse(data).getAsJsonObject();

src/main/resources/currentversion.csv

@@ -1,2 +1,2 @@
 beta
-1.3.2
+1.4.0

src/main/resources/servertypes.csv

@@ -1,6 +1,6 @@
 Vanilla;Latest,Snapshot,1.17.1,1.16.5,1.15.2,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2,1.9.4,1.8.9,1.7.10,1.6.4,1.5.2,1.4.7,1.3.2,1.2.5;https://launchermeta.mojang.com/mc/game/version_manifest.json;"release":";";https://s3.amazonaws.com/Minecraft.Download/versions/
 Spigot;Latest,1.17.1,1.16.5,1.15.2,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2,1.9.4,1.9.4,1.8.8,1.7.10,1.6.4-R2.1,1.5.2-R1.1,1.4.7-R1.1;https://static.knarcraft.net/archive/downloads/minecraftserverjars/Spigot/;spigot-
-Paper;1.17.1,1.16.5,1.15.2,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2,1.9.4,1.8.8;https://static.knarcraft.net/archive/downloads/minecraftserverjars/Paper/;Paper-
+Paper;1.17.1,1.16.5,1.15.2,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2,1.9.4,1.8.8;https://papermc.io/api/v1/paper/;"latest":;,;https://papermc.io/api/v1/paper/
 #SpongeVanilla;1.12.2,1.11.2,1.10.2,1.8.9;https://dl-api.spongepowered.org/v1/org.spongepowered/spongevanilla/downloads?type=stable&minecraft=;"version":";",;https://repo.spongepowered.org/maven/org/spongepowered/spongevanilla/;/spongevanilla-
 Craftbukkit;Latest,1.17.1,1.16.5,1.15.2,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2,1.9.4,1.8.8,1.7.10-R0.1,1.6.4-R2.0,1.5.2-R1.0,1.4.6-R0.3,1.3.2-R3.0,1.2.5-R2.0,1.1-R6,1.0.1-R1,b1.8.1,b1.7.3;https://static.knarcraft.net/archive/downloads/minecraftserverjars/Bukkit/;craftbukkit-
 #SpongeForge;1.12.2,1.11.2,1.10.2;https://dl-api.spongepowered.org/v1/org.spongepowered/spongeforge/downloads?type=stable&minecraft=;"version":";",;https://repo.spongepowered.org/maven/org/spongepowered/spongeforge/;/spongeforge-

src/test/java/net/knarcraft/minecraftserverlauncher/server/ServerTest.java

@@ -11,7 +11,7 @@ public class ServerTest {
 
     @Test
     public void fromStringTest() throws ConfigurationException {
-        Server server = Server.fromString("asd;/home/;false;Bukkit;1.10.2;4G;");
+        Server server = ServerHandler.fromString("asd;/home/;false;Bukkit;1.10.2;4G;");
         assertEquals("asd", server.getName());
         assertEquals("/home/", server.getPath());
         assertFalse(server.isEnabled());

src/test/java/net/knarcraft/minecraftserverlauncher/server/ServerVersionContainerTest.java

@@ -38,7 +38,7 @@ public class ServerVersionContainerTest {
         serverVersionContainer.reset();
         System.out.println(serverVersionContainer.toString());
         assertEquals("vanillaVersion;null\nsnapshotVersion;null\nbungeeVersion;null\nwaterfallVersions;\n" +
-                        "travertineVersions;\nspongeVanillaVersions;\nspongeForgeVersions;\ndownloadedBuildToolsVersion;null",
+                        "travertineVersions;\npaperVersions;\nspongeVanillaVersions;\nspongeForgeVersions;\ndownloadedBuildToolsVersion;null",
                 serverVersionContainer.toString());
     }