Fix fabric development environment launch

common/src/main/java/com/dfsek/terra/api/util/JarUtil.java

@@ -6,13 +6,21 @@ import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.Enumeration;
+import java.util.UUID;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.jar.JarEntry;
 import java.util.jar.JarFile;
 
 public class JarUtil {
+
+    private static final AtomicReference<File> terraModJar = new AtomicReference<>(null);
+
     public static void copyResourcesToDirectory(JarFile fromJar, String sourceDir, String destDir) throws IOException {
         for(Enumeration<JarEntry> entries = fromJar.entries(); entries.hasMoreElements(); ) {
             JarEntry entry = entries.nextElement();
@@ -38,7 +46,28 @@ public class JarUtil {
     }
 
     public static JarFile getJarFile() throws URISyntaxException, IOException {
-        return new JarFile(new File(getJarURL().toURI()));
+        final File _jarFile1 = terraModJar.get();
+        if(_jarFile1 != null) return new JarFile(_jarFile1);
+        synchronized(terraModJar) {
+            final File _jarFile2 = terraModJar.get();
+            if(_jarFile2 != null) return new JarFile(_jarFile2);
+
+            // uncached here
+            final URI jarURI = getJarURL().toURI();
+            if(jarURI.getScheme() == null || !jarURI.getScheme().equalsIgnoreCase("file")) {
+                final File tempFile = File.createTempFile("terra-jar-" + UUID.randomUUID(), ".jar");
+                try(final FileOutputStream out = new FileOutputStream(tempFile)) {
+                    Files.copy(Paths.get(jarURI), out);
+                }
+                tempFile.deleteOnExit();
+                terraModJar.set(tempFile);
+                return new JarFile(tempFile);
+            } else {
+                final File jarFile = new File(jarURI);
+                terraModJar.set(jarFile);
+                return new JarFile(jarFile);
+            }
+        }
     }
 
     public static URL getJarURL() {