alternatively to creating a classloader for the application at runtim…

…e, allow to configure at fxlauncher classloader at boot-time and add the new classpath-entries to this classloader. this should avoid problems where the jdk itself does use Class.forName and might not find application-classes due to using the wrong classloader.

src/main/java/fxlauncher/FxlauncherClassCloader.java

@@ -0,0 +1,68 @@
+package fxlauncher;
+
+import java.io.File;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Created by im on 22.02.17.
+ */
+public class FxlauncherClassCloader extends URLClassLoader
+{
+    public FxlauncherClassCloader(ClassLoader parentClassLoader)
+    {
+        super(buildClasspath(System.getProperty("java.class.path")), parentClassLoader);
+    }
+
+    void addUrls(List<URL> urls)
+    {
+        for (URL url : urls)
+        {
+            this.addURL(url);
+        }
+    }
+
+    private static URL[] buildClasspath(String classPath)
+    {
+        if (classPath == null || classPath.trim().length() < 1)
+        {
+            return new URL[0];
+        }
+
+        List<URL> urls = new ArrayList<>();
+
+        int pos;
+        while ((pos = classPath.indexOf(File.pathSeparatorChar)) > -1)
+        {
+            String part = classPath.substring(0, pos);
+
+            addClasspathPart(urls, part);
+
+            classPath = classPath.substring(pos + 1);
+        }
+
+        addClasspathPart(urls, classPath);
+
+        return urls.toArray(new URL[urls.size()]);
+    }
+
+    private static void addClasspathPart(List<URL> urls, String part)
+    {
+        if (part == null || part.trim().length() < 1)
+        {
+            return;
+        }
+
+        try
+        {
+            urls.add(new File(part).toURI().toURL());
+        }
+        catch (MalformedURLException e)
+        {
+            throw new RuntimeException(e);
+        }
+    }
+}

src/main/java/fxlauncher/Launcher.java

@@ -153,10 +153,24 @@ private void createUpdateWrapper() {
         });
     }
 
-    private URLClassLoader createClassLoader(Path cacheDir) {
+    private ClassLoader createClassLoader(Path cacheDir) {
         List<URL> libs = manifest.files.stream().filter(LibraryFile::loadForCurrentPlatform).map(it -> it.toURL(cacheDir)).collect(Collectors.toList());
 
-        return new URLClassLoader(libs.toArray(new URL[libs.size()]));
+        ClassLoader systemClassLoader = ClassLoader.getSystemClassLoader();
+        if (systemClassLoader instanceof FxlauncherClassCloader)
+        {
+            ((FxlauncherClassCloader) systemClassLoader).addUrls(libs);
+            return systemClassLoader;
+        }
+        else
+        {
+            ClassLoader classLoader = new URLClassLoader(libs.toArray(new URL[libs.size()]));
+            FXMLLoader.setDefaultClassLoader(classLoader);
+            Thread.currentThread().setContextClassLoader(classLoader);
+            Platform.runLater(() -> Thread.currentThread().setContextClassLoader(classLoader));
+
+            return classLoader;
+        }
     }
 
     private void launchAppFromManifest(boolean showWhatsnew) throws Exception {
@@ -247,10 +261,7 @@ private void createApplication() throws Exception {
 
         Path cacheDir = manifest.resolveCacheDir(getParameters() != null ? getParameters().getNamed() : null);
 
-        URLClassLoader classLoader = createClassLoader(cacheDir);
-        FXMLLoader.setDefaultClassLoader(classLoader);
-        Thread.currentThread().setContextClassLoader(classLoader);
-        Platform.runLater(() -> Thread.currentThread().setContextClassLoader(classLoader));
+        ClassLoader classLoader = createClassLoader(cacheDir);
         Class<? extends Application> appclass = (Class<? extends Application>) classLoader.loadClass(manifest.launchClass);
 
         PlatformImpl.runAndWait(() ->