Move backgrounds outside of jar file

.idea/jarRepositories.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RemoteRepositoriesConfiguration">
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Maven Central repository" />
+      <option name="url" value="https://repo1.maven.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="jboss.community" />
+      <option name="name" value="JBoss Community repository" />
+      <option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="MavenRepo" />
+      <option name="name" value="MavenRepo" />
+      <option name="url" value="https://repo.maven.apache.org/maven2/" />
+    </remote-repository>
+  </component>
+</project>

src/main/java/tech/nevets/signaturecardgen/Location.java

@@ -6,9 +6,9 @@ import com.google.gson.JsonElement;
 
 import javax.imageio.ImageIO;
 import java.awt.image.BufferedImage;
+import java.io.File;
 import java.io.FileReader;
 import java.io.IOException;
-import java.net.URL;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -50,11 +50,10 @@ public class Location {
     }
 
     public void loadBackground() {
-        URL backgroundURL = this.getClass().getResource("/backgrounds/" + id + ".png");
-        if (backgroundURL == null) backgroundURL = this.getClass().getResource("/backgrounds/default.png");
+        File backgroundFile = new File("./backgrounds/" + id + ".png");
+        if (!backgroundFile.exists()) backgroundFile = new File("./backgrounds/default.png");
         try {
-            assert backgroundURL != null;
-            background = ImageIO.read(backgroundURL);
+            background = ImageIO.read(backgroundFile);
         } catch (IOException e) {
             e.printStackTrace();
         }