[Load] Reject device paths with empty nodes before database auto-creation

iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/analyze/load/TreeSchemaAutoCreatorAndVerifier.java

@@ -359,6 +359,12 @@ private void autoCreateDatabase()
       final PartialPath devicePath = new PartialPath(device);
 
       final String[] devicePrefixNodes = devicePath.getNodes();
+      for (final String node : devicePrefixNodes) {
+        if (node == null || node.isEmpty()) {
+          throw new LoadAnalyzeException(
+              new IllegalPathException(devicePath.getFullPath()).getMessage());
+        }
+      }
       if (devicePrefixNodes.length < databasePrefixNodesLength) {
         throw new LoadAnalyzeException(
             String.format(

iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/plan/analyze/load/LoadTsFileAnalyzerTest.java

@@ -200,6 +200,35 @@ public void testTreeSchemaVerifierShouldThrowMismatchWhenVerifyingDataType() thr
     }
   }
 
+  @Test
+  public void testTreeSchemaVerifierShouldRejectDeviceWithEmptyPathNode() throws Exception {
+    final File tsFile = File.createTempFile("load-tree-illegal-device", ".tsfile");
+
+    try (final LoadTsFileAnalyzer analyzer =
+        new LoadTsFileAnalyzer(
+            LoadTsFileStatement.createUnchecked(tsFile.getAbsolutePath()),
+            false,
+            new MPPQueryContext(new QueryId("load_tree_illegal_device_test")))) {
+      final TreeSchemaAutoCreatorAndVerifier verifier =
+          new TreeSchemaAutoCreatorAndVerifier(analyzer);
+      try {
+        final IDeviceID device = new StringArrayDeviceID(new String[] {"root", ""});
+        getTreeSchemaCache(verifier)
+            .addTimeSeries(device, new MeasurementSchema("s1", TSDataType.INT32));
+
+        final InvocationTargetException exception =
+            Assert.assertThrows(
+                InvocationTargetException.class,
+                () -> getAutoCreateDatabaseMethod().invoke(verifier));
+        Assert.assertTrue(exception.getCause() instanceof LoadAnalyzeException);
+      } finally {
+        verifier.close();
+      }
+    } finally {
+      Assert.assertTrue(tsFile.delete());
+    }
+  }
+
   @Test
   public void testPipeGeneratedLoadMissingSchemaShouldBeTemporaryWhenAutoCreateDisabled()
       throws Exception {
@@ -316,6 +345,13 @@ private Method getVerifyTreeSchemaMethod() throws NoSuchMethodException {
     return method;
   }
 
+  private Method getAutoCreateDatabaseMethod() throws NoSuchMethodException {
+    final Method method =
+        TreeSchemaAutoCreatorAndVerifier.class.getDeclaredMethod("autoCreateDatabase");
+    method.setAccessible(true);
+    return method;
+  }
+
   private org.apache.iotdb.commons.queryengine.plan.relational.metadata.TableSchema
       createTableSchema(final TSDataType fieldType) {
     return new org.apache.iotdb.commons.queryengine.plan.relational.metadata.TableSchema(