fix: avoid NullPointerException in BigQuery.create() when the duplicated job cannot be re-fetched

The duplicate-job-id handler dereferences the getJob(...) re-fetch
unconditionally, but getJob returns null when the job cannot be seen -
most commonly a job outside the US multi-region looked up through a
JobId that carries no location. Guard it and fall through to the
original Already Exists exception, as the random-id branch below
already does.

Fixes #14025

Author: laughingman7743

java-bigquery/google-cloud-bigquery/src/main/java/com/google/cloud/bigquery/BigQueryImpl.java

@@ -608,18 +608,20 @@ public com.google.api.services.bigquery.model.Job call() throws IOException {
             // If the Job ALREADY EXISTS, retrieve it.
             Job job = this.getJob(jobInfo.getJobId(), JobOption.fields(JobField.STATISTICS));
 
-            long jobCreationTime = job.getStatistics().getCreationTime();
-            long jobMinStaleTime = System.currentTimeMillis();
-            long jobMaxStaleTime =
-                java.time.Instant.ofEpochMilli(jobMinStaleTime)
-                    .minus(1, java.time.temporal.ChronoUnit.DAYS)
-                    .toEpochMilli();
-
-            // Only return the job if it has been created in the past 24 hours.
-            // This is assuming any job older than 24 hours is a valid duplicate JobID
-            // and not a false positive like b/290419183
-            if (jobCreationTime >= jobMaxStaleTime && jobCreationTime <= jobMinStaleTime) {
-              return job;
+            if (job != null) {
+              long jobCreationTime = job.getStatistics().getCreationTime();
+              long jobMinStaleTime = System.currentTimeMillis();
+              long jobMaxStaleTime =
+                  java.time.Instant.ofEpochMilli(jobMinStaleTime)
+                      .minus(1, java.time.temporal.ChronoUnit.DAYS)
+                      .toEpochMilli();
+
+              // Only return the job if it has been created in the past 24 hours.
+              // This is assuming any job older than 24 hours is a valid duplicate JobID
+              // and not a false positive like b/290419183
+              if (jobCreationTime >= jobMaxStaleTime && jobCreationTime <= jobMinStaleTime) {
+                return job;
+              }
             }
           }
         }

java-bigquery/google-cloud-bigquery/src/test/java/com/google/cloud/bigquery/BigQueryImplTest.java

@@ -2144,6 +2144,37 @@ void testCreateJobTryGetNotRandom() throws IOException {
             any(String.class), eq(id), eq((String) null), eq(withStatisticOption));
   }
 
+  @Test
+  void testCreateJobTryGetNotRandomJobNotFound() throws IOException {
+    Map<BigQueryRpc.Option, ?> withStatisticOption = optionMap(JobOption.fields(STATISTICS));
+    final String id = "testCreateJobTryGet-id";
+    String query = "SELECT * in FOO";
+
+    when(bigqueryRpcMock.createSkipExceptionTranslation(
+            jobCapture.capture(), eq(EMPTY_RPC_OPTIONS)))
+        .thenThrow(
+            new BigQueryException(
+                409,
+                "already exists, for some reason",
+                new RuntimeException("Already Exists: Job")));
+    when(bigqueryRpcMock.getJobSkipExceptionTranslation(
+            any(String.class), eq(id), eq((String) null), eq(withStatisticOption)))
+        .thenThrow(new BigQueryException(404, "Job not found"));
+
+    bigquery = options.getService();
+    BigQueryException exception =
+        Assertions.assertThrows(
+            BigQueryException.class,
+            () ->
+                ((BigQueryImpl) bigquery)
+                    .create(JobInfo.of(JobId.of(id), QueryJobConfiguration.of(query))));
+    assertEquals(409, exception.getCode());
+    assertEquals("already exists, for some reason", exception.getMessage());
+    verify(bigqueryRpcMock)
+        .getJobSkipExceptionTranslation(
+            any(String.class), eq(id), eq((String) null), eq(withStatisticOption));
+  }
+
   @Test
   void testCreateJobWithProjectId() throws IOException {
     JobInfo jobInfo =