diff --git a/python/raydp/spark/ray_cluster.py b/python/raydp/spark/ray_cluster.py
index 10816d25..54aec3b9 100644
--- a/python/raydp/spark/ray_cluster.py
+++ b/python/raydp/spark/ray_cluster.py
@@ -17,20 +17,74 @@
 
 import glob
 import os
+import re
+import subprocess
 import sys
 import platform
 import pyspark
-from typing import Any, Dict
+from typing import Any, Dict, Optional
 
 import ray
 from pyspark.sql.session import SparkSession
 
 from raydp.services import Cluster
-from .ray_cluster_master import RAYDP_SPARK_MASTER_SUFFIX, SPARK_RAY_LOG4J_FACTORY_CLASS_KEY
-from .ray_cluster_master import SPARK_LOG4J_CONFIG_FILE_NAME, RAY_LOG4J_CONFIG_FILE_NAME
-from .ray_cluster_master import RayDPSparkMaster, SPARK_JAVAAGENT, SPARK_PREFER_CLASSPATH
+from .ray_cluster_master import (RAYDP_SPARK_MASTER_SUFFIX, SPARK_RAY_LOG4J_FACTORY_CLASS_KEY,
+                                 SPARK_LOG4J_CONFIG_FILE_NAME, RAY_LOG4J_CONFIG_FILE_NAME,
+                                 RayDPSparkMaster, SPARK_JAVAAGENT, SPARK_PREFER_CLASSPATH,
+                                 RAYDP_APPMASTER_EXTRA_JAVA_OPTIONS)
 from raydp import versions
 
+_JDK17_ADD_OPENS = " ".join([
+    "-XX:+IgnoreUnrecognizedVMOptions",
+    "--add-opens=java.base/java.lang=ALL-UNNAMED",
+    "--add-opens=java.base/java.lang.invoke=ALL-UNNAMED",
+    "--add-opens=java.base/java.io=ALL-UNNAMED",
+    "--add-opens=java.base/java.net=ALL-UNNAMED",
+    "--add-opens=java.base/java.nio=ALL-UNNAMED",
+    "--add-opens=java.base/java.math=ALL-UNNAMED",
+    "--add-opens=java.base/java.text=ALL-UNNAMED",
+    "--add-opens=java.base/java.util=ALL-UNNAMED",
+    "--add-opens=java.base/java.util.concurrent=ALL-UNNAMED",
+    "--add-opens=java.base/java.util.concurrent.atomic=ALL-UNNAMED",
+    "--add-opens=java.base/sun.nio.ch=ALL-UNNAMED",
+    "--add-opens=java.base/sun.nio.cs=ALL-UNNAMED",
+    "--add-opens=java.base/sun.security.action=ALL-UNNAMED",
+    "--add-opens=java.base/sun.util.calendar=ALL-UNNAMED",
+])
+
+_cached_java_version: Optional[int] = None
+
+
+def _get_java_major_version() -> Optional[int]:
+    """Return the major version of the default ``java`` command, or None if
+    it cannot be determined."""
+    global _cached_java_version
+    if _cached_java_version is not None:
+        return _cached_java_version
+    try:
+        out = subprocess.check_output(
+            ["java", "-version"], stderr=subprocess.STDOUT, timeout=10
+        ).decode("utf-8", errors="replace")
+        match = re.search(r'"(\d+)[\._]', out)
+        if match:
+            major = int(match.group(1))
+            # Java 1.x style (e.g. "1.8.0_xxx") means major = 8
+            if major == 1:
+                m2 = re.search(r'"1\.(\d+)', out)
+                if m2:
+                    major = int(m2.group(1))
+            _cached_java_version = major
+            return major
+    except Exception:
+        pass
+    return None
+
+
+def _needs_add_opens() -> bool:
+    """Return True if the JVM is version 17+ and needs ``--add-opens`` flags."""
+    ver = _get_java_major_version()
+    return ver is not None and ver >= 17
+
 
 class SparkCluster(Cluster):
     def __init__(self,
@@ -176,13 +230,23 @@ def _prepare_spark_configs(self):
                       "If used with autoscaling, calculate it from max_workers.",
                       file=sys.stderr)
 
+        # On JDK 17+, inject --add-opens flags for driver and app master when
+        # the user has not explicitly provided them.
+        add_opens = _JDK17_ADD_OPENS if _needs_add_opens() else ""
+
+        if add_opens and "spark.driver.extraJavaOptions" not in self._configs:
+            self._configs["spark.driver.extraJavaOptions"] = add_opens
+
+        if add_opens and RAYDP_APPMASTER_EXTRA_JAVA_OPTIONS not in self._configs:
+            self._configs[RAYDP_APPMASTER_EXTRA_JAVA_OPTIONS] = add_opens
+
         # set spark.driver.extraJavaOptions for driver (spark-submit)
         java_opts = ["-javaagent:" + self._configs[SPARK_JAVAAGENT],
                      "-D" + SPARK_RAY_LOG4J_FACTORY_CLASS_KEY + "=" + versions.SPARK_LOG4J_VERSION,
                      "-D" + versions.SPARK_LOG4J_CONFIG_FILE_NAME_KEY + "=" +
                      self._configs[SPARK_LOG4J_CONFIG_FILE_NAME]
                      ]
-        # Append to existing driver options if they exist (e.g., JDK 17+ flags)
+        # Append to existing driver options (user-provided or auto-injected above)
         existing_driver_opts = self._configs.get("spark.driver.extraJavaOptions", "")
         if existing_driver_opts:
             all_opts = existing_driver_opts + " " + " ".join(java_opts)