diff --git a/integration_test_suite/integration_tests/src/test/java/io/prometheus/jmx/test/http/authentication/AuthenticatorClassTest.java b/integration_test_suite/integration_tests/src/test/java/io/prometheus/jmx/test/http/authentication/AuthenticatorClassTest.java
index bf0dac1e..87c1b47f 100644
--- a/integration_test_suite/integration_tests/src/test/java/io/prometheus/jmx/test/http/authentication/AuthenticatorClassTest.java
+++ b/integration_test_suite/integration_tests/src/test/java/io/prometheus/jmx/test/http/authentication/AuthenticatorClassTest.java
@@ -20,7 +20,6 @@
 import io.prometheus.jmx.test.common.ExporterTestEnvironment;
 import io.prometheus.jmx.test.support.JmxExporterMode;
 import java.util.stream.Stream;
-
 import org.verifyica.api.ArgumentContext;
 import org.verifyica.api.Verifyica;
 
diff --git a/integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/CustomAuthenticator.java b/integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/CustomAuthenticator.java
index 22a5d5f8..37d1b7c3 100644
--- a/integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/CustomAuthenticator.java
+++ b/integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/CustomAuthenticator.java
@@ -18,39 +18,95 @@
 import com.sun.net.httpserver.Headers;
 import com.sun.net.httpserver.HttpExchange;
 import com.sun.net.httpserver.HttpPrincipal;
-import com.sun.security.auth.UserPrincipal;
+import java.io.Serializable;
 import java.nio.charset.StandardCharsets;
+import java.security.Principal;
 import java.util.Base64;
+import java.util.Objects;
 import javax.security.auth.Subject;
 
+/** Example custom authenticator */
 public class CustomAuthenticator extends Authenticator {
 
+    private static final String AUTHORIZATION = "Authorization";
+    private static final String BASIC = "Basic";
+
+    private static final String USERNAME = "Prometheus";
+    private static final String PASSWORD = "secret";
+
     @Override
-    public Result authenticate(HttpExchange exch) {
+    public Result authenticate(HttpExchange httpExchange) {
         // nothing too custom, so the test works, just to demonstrate that it is plug-able
-        Headers rmap = exch.getRequestHeaders();
-        String auth = rmap.getFirst("Authorization");
-        if (auth == null) {
+        Headers headers = httpExchange.getRequestHeaders();
+
+        String authorization = headers.getFirst(AUTHORIZATION);
+        if (authorization == null) {
             return new Authenticator.Retry(401);
         }
-        int sp = auth.indexOf(' ');
-        if (sp == -1 || !auth.substring(0, sp).equals("Basic")) {
+
+        int space = authorization.indexOf(' ');
+        if (space == -1 || !authorization.substring(0, space).equals(BASIC)) {
             return new Authenticator.Failure(401);
         }
-        byte[] b = Base64.getDecoder().decode(auth.substring(sp + 1));
-        String userpass = new String(b, StandardCharsets.UTF_8);
-        int colon = userpass.indexOf(':');
-        String uname = userpass.substring(0, colon);
-        String pass = userpass.substring(colon + 1);
 
-        if ("Prometheus".equals(uname) && "secret".equals(pass)) {
+        byte[] usernamePasswordBytes =
+                Base64.getDecoder().decode(authorization.substring(space + 1));
+        String usernamePassword = new String(usernamePasswordBytes, StandardCharsets.UTF_8);
+        int colon = usernamePassword.indexOf(':');
+        String username = usernamePassword.substring(0, colon);
+        String password = usernamePassword.substring(colon + 1);
+
+        if (USERNAME.equals(username) && PASSWORD.equals(password)) {
             Subject subject = new Subject();
-            subject.getPrincipals().add(new UserPrincipal(uname));
+            subject.getPrincipals().add(new UserPrincipal(username));
             // to communicate an authenticated subject for subsequent handler calls via Subject.doAs
-            exch.setAttribute("io.prometheus.jmx.CustomAuthenticatorSubjectAttribute", subject);
-            return new Authenticator.Success(new HttpPrincipal(uname, "/"));
+            httpExchange.setAttribute(
+                    "io.prometheus.jmx.CustomAuthenticatorSubjectAttribute", subject);
+            return new Authenticator.Success(new HttpPrincipal(username, "/"));
         } else {
             return new Authenticator.Failure(401);
         }
     }
+
+    /**
+     * Class to implement Principal
+     *
+     * <p>Required for ibmjava:8 since it doesn't provide com.sun.security.auth.UserPrincipal
+     */
+    public static class UserPrincipal implements Principal, Serializable {
+
+        private final String name;
+
+        /**
+         * Constructor
+         *
+         * @param name name
+         */
+        public UserPrincipal(String name) {
+            this.name = Objects.requireNonNull(name, "Name cannot be null");
+        }
+
+        @Override
+        public String getName() {
+            return name;
+        }
+
+        @Override
+        public String toString() {
+            return "UserPrincipal{" + "name='" + name + '\'' + '}';
+        }
+
+        @Override
+        public boolean equals(Object object) {
+            if (this == object) return true;
+            if (object == null || getClass() != object.getClass()) return false;
+            UserPrincipal that = (UserPrincipal) object;
+            return Objects.equals(name, that.name);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hashCode(name);
+        }
+    }
 }