diff --git a/0001-Drop-Assertions.callerIs.patch b/0001-Drop-Assertions.callerIs.patch
new file mode 100644
index 0000000..fcaa540
--- /dev/null
+++ b/0001-Drop-Assertions.callerIs.patch
@@ -0,0 +1,36 @@
+From a723b73f85f586e855514cce078de3f153c9e201 Mon Sep 17 00:00:00 2001
+From: "Endi S. Dewata" <edewata@redhat.com>
+Date: Fri, 4 Jun 2021 15:59:34 -0500
+Subject: [PATCH] Drop Assertions.callerIs()
+
+---
+ src/main/java/org/jboss/jdeparser/Assertions.java | 9 ---------
+ 1 file changed, 9 deletions(-)
+
+diff --git a/src/main/java/org/jboss/jdeparser/Assertions.java b/src/main/java/org/jboss/jdeparser/Assertions.java
+index 017c645..a8c0129 100644
+--- a/src/main/java/org/jboss/jdeparser/Assertions.java
++++ b/src/main/java/org/jboss/jdeparser/Assertions.java
+@@ -18,19 +18,10 @@
+ 
+ package org.jboss.jdeparser;
+ 
+-import sun.reflect.Reflection;
+-
+ /**
+  * @author <a href="mailto:david.lloyd@redhat.com">David M. Lloyd</a>
+  */
+ class Assertions {
+-    static boolean callerIs(Class<?> clazz) {
+-        try {
+-            return Reflection.getCallerClass(3) == clazz;
+-        } catch (Throwable ignored) {}
+-        // dunno
+-        return true;
+-    }
+ 
+     @SuppressWarnings("ConstantConditions")
+     static boolean alwaysTrue(boolean expr) {
+-- 
+2.31.1
+
diff --git a/jdeparser.spec b/jdeparser.spec
index f7f1975..b36bcf1 100644
--- a/jdeparser.spec
+++ b/jdeparser.spec
@@ -3,15 +3,16 @@
 
 Name:             jdeparser
 Version:          2.0.3
-Release:          6%{?dist}
+Release:          7%{?dist}
 Summary:          Source generator library for Java
 License:          ASL 2.0
 URL:              https://github.com/jdeparser/jdeparser2
 # old repos https://github.com/jdeparser/jdeparser
 Source0:          %{url}/archive/%{namedversion}/%{name}-%{namedversion}.tar.gz
+Patch1:           0001-Drop-Assertions.callerIs.patch
+
 BuildArch:        noarch
 
-BuildRequires:    java-1.8.0-openjdk-devel
 BuildRequires:    maven-local
 BuildRequires:    mvn(junit:junit)
 BuildRequires:    mvn(org.jboss:jboss-parent:pom:)
@@ -29,11 +30,9 @@ Summary:        Javadoc for %{name}
 This package contains the API documentation for %{name}.
 
 %prep
-%setup -q -n jdeparser2-%{namedversion}
+%autosetup -n jdeparser2-%{namedversion} -p 1
 
 %build
-# Use Java 8 as sun.reflect.Reflection is removed in Java 11.
-export JAVA_HOME=%{_jvmdir}/java-1.8.0
 %mvn_build
 
 %install
@@ -46,6 +45,9 @@ export JAVA_HOME=%{_jvmdir}/java-1.8.0
 %license LICENSE.txt
 
 %changelog
+* Fri Jun 04 2021 Dogtag PKI Team <pki-devel@redhat.com> - 2.0.3-7
+- Drop Assertions.callerIs()
+
 * Tue Jan 26 2021 Fedora Release Engineering <releng@fedoraproject.org> - 2.0.3-6
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_34_Mass_Rebuild