[SPARK-44242] Improve Max Heap not set check

### What changes were proposed in this pull request?
Currently if any Xmx string is available in the driver java options even if not related to Max Heap setting the job sumission failed
For Ex. this command failed
`./bin/spark-submit --class org.apache.spark.examples.SparkPi --conf "spark.driver.extraJavaOptions=-Dtest=Xmx"  examples/jars/spark-examples_2.12-3.4.1.jar 100`

### Why are the changes needed?
The command should any failed if the -Xmx argument is set not if it is part of another parameter or string

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
Added a unitary test

Closes #41806 from ashangit/nfraison/SPARK-44242.

Authored-by: Nicolas Fraison <nicolas.fraison@datadoghq.com>
Signed-off-by: Mridul Muralidharan <mridul<at>gmail.com>

Author: ashangit

launcher/src/main/java/org/apache/spark/launcher/SparkSubmitCommandBuilder.java

@@ -311,11 +311,15 @@ private List<String> buildSparkSubmitCommand(Map<String, String> env)
   }
 
   private void checkJavaOptions(String javaOptions) {
-    if (!isEmpty(javaOptions) && javaOptions.contains("Xmx")) {
-      String msg = String.format("Not allowed to specify max heap(Xmx) memory settings through " +
-        "java options (was %s). Use the corresponding --driver-memory or " +
-        "spark.driver.memory configuration instead.", javaOptions);
-      throw new IllegalArgumentException(msg);
+    if (!isEmpty(javaOptions)) {
+      for (String javaOption: CommandBuilderUtils.parseOptionString(javaOptions)) {
+        if (javaOption.startsWith("-Xmx")) {
+            String msg = String.format("Not allowed to specify max heap(Xmx) memory settings " +
+              "through java options (was %s). Use the corresponding --driver-memory or " +
+              "spark.driver.memory configuration instead.", javaOptions);
+            throw new IllegalArgumentException(msg);
+        }
+      }
     }
   }
 

launcher/src/test/java/org/apache/spark/launcher/SparkSubmitCommandBuilderSuite.java

@@ -72,6 +72,36 @@ public void testCliHelpAndNoArg() throws Exception {
       cmd.contains("org.apache.spark.deploy.SparkSubmit"));
   }
 
+  @Test(expected = IllegalArgumentException.class)
+  public void testCheckJavaOptionsThrowException() throws Exception {
+    Map<String, String> env = new HashMap<>();
+    List<String> sparkSubmitArgs = Arrays.asList(
+      parser.MASTER,
+      "local",
+      parser.DRIVER_CLASS_PATH,
+      "/driverCp",
+      parser.DRIVER_JAVA_OPTIONS,
+      "-Xmx64g -Dprop=Other -Dprop1=\"-Xmx -Xmx\" -Dprop2=\"-Xmx '-Xmx\" " +
+        "-Dprop3='-Xmx -Xmx' -Dprop4='-Xmx \"-Xmx'",
+      SparkLauncher.NO_RESOURCE);
+    buildCommand(sparkSubmitArgs, env);
+  }
+
+  @Test
+  public void testCheckJavaOptions() throws Exception {
+    Map<String, String> env = new HashMap<>();
+    List<String> sparkSubmitArgs = Arrays.asList(
+      parser.MASTER,
+      "local",
+      parser.DRIVER_CLASS_PATH,
+      "/driverCp",
+      parser.DRIVER_JAVA_OPTIONS,
+      "-Dprop=-Xmx -Dprop1=\"-Xmx -Xmx\" -Dprop2=\"-Xmx '-Xmx\" " +
+        "-Dprop3='-Xmx -Xmx' -Dprop4='-Xmx \"-Xmx'",
+      SparkLauncher.NO_RESOURCE);
+    buildCommand(sparkSubmitArgs, env);
+  }
+
   @Test
   public void testCliKillAndStatus() throws Exception {
     List<String> params = Arrays.asList("driver-20160531171222-0000");