Created the SpigotInstaller.java

src/main/java/de/gnmyt/mcdash/api/installer/SpigotInstaller.java

@@ -0,0 +1,46 @@
+package de.gnmyt.mcdash.api.installer;
+
+import de.gnmyt.mcdash.api.Logger;
+import de.gnmyt.mcdash.api.ServerVersionManager;
+
+import java.io.File;
+import java.util.ArrayList;
+
+public class SpigotInstaller implements VersionInstaller {
+
+    private static final Logger LOG = new Logger(SpigotInstaller.class);
+
+    private final ArrayList<String> SPIGOT_URLS = new ArrayList<>();
+
+    public SpigotInstaller() {
+        SPIGOT_URLS.add("https://download.getbukkit.org/spigot/spigot-%s.jar");
+        SPIGOT_URLS.add("https://cdn.getbukkit.org/spigot/spigot-%s.jar");
+        SPIGOT_URLS.add("https://cdn.getbukkit.org/spigot/spigot-%s-R0.1-SNAPSHOT-latest.jar");
+    }
+
+    @Override
+    public boolean installVersion(String software, String version) {
+        try {
+            File file = new File(ServerVersionManager.getVersionFolder(), software + "-" + version + ".jar");
+
+            if (file.exists()) {
+                LOG.info("The version " + version + " of the software " + software + " is already installed");
+                return true;
+            }
+
+            for (String url : SPIGOT_URLS) {
+                String downloadUrl = String.format(url, version);
+
+                if (downloadFile(downloadUrl, file)) {
+                    LOG.info("The version " + version + " of the software " + software + " has been installed");
+                    return true;
+                }
+            }
+
+            return false;
+        } catch (Exception e) {
+            LOG.error("An error occurred while installing the spigot version", e);
+            return false;
+        }
+    }
+}