1 files changed, 55 insertions, 0 deletions
diff --git a/src/main/java/at/gv/egiz/moazs/util/JAXBClassNotFoundFix.java b/src/main/java/at/gv/egiz/moazs/util/JAXBClassNotFoundFix.java
new file mode 100644
index 0000000..9e72286
--- /dev/null
+++ b/src/main/java/at/gv/egiz/moazs/util/JAXBClassNotFoundFix.java
@@ -0,0 +1,55 @@
+package at.gv.egiz.moazs.util;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Component;
+
+import java.util.function.Supplier;
+
+import static at.gv.egiz.moazs.MoaZSException.moaZSException;
+
+@Component
+public class JAXBClassNotFoundFix {
+
+    private static final Logger log = LoggerFactory.getLogger(JAXBClassNotFoundFix.class);
+
+    /**
+     * Solves JAXB's "ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory" in Java >= 9
+     * by running func in a dedicated thread which has its context classloader replaced with a classloader that finds
+     * the ContextFactory.
+     *
+     * See https://sjhannah.com/blog/2018/11/21/jaxb-hell-on-jdk-9/
+     * Note: "runInTheadWithClassClassLoader" is not a typo.
+     * @param func function that is called in a dedicated thread.
+     * @param <A> return value of func.
+     * @return
+     */
+    public static <A> A runInTheadWithClassClassLoader(Supplier<A> func) {
+
+        final Object[] result = new Object[1];
+        final Exception[] error = new Exception[1];
+
+        Thread t = new Thread(() -> {
+            try {
+                result[0] = func.get();
+            } catch (Exception ex) {
+                error[0] = ex;
+            }
+        });
+
+        t.setContextClassLoader(JAXBClassNotFoundFix.class.getClassLoader());
+        t.start();
+
+        try {
+            t.join();
+        } catch (InterruptedException ex) {
+            log.error("Interrupted. ", ex);
+        }
+
+        if (error[0] != null) {
+            throw moaZSException("Could not run function.", error[0]);
+        }
+
+        return (A)result[0];
+    }
+}