[HUDI-1845] Exception Throws When Sync Non-Partitioned Table To Hive With MultiPartKeysValueExtractor (#2876)

hudi-sync/hudi-hive-sync/src/main/java/org/apache/hudi/hive/MultiPartKeysValueExtractor.java

@@ -18,6 +18,7 @@
 
 package org.apache.hudi.hive;
 
+import java.util.Collections;
 import org.apache.hudi.common.util.ValidationUtils;
 
 import java.util.Arrays;
@@ -31,6 +32,11 @@ public class MultiPartKeysValueExtractor implements PartitionValueExtractor {
 
   @Override
   public List<String> extractPartitionValuesInPath(String partitionPath) {
+    // If the partitionPath is empty string( which means none-partition table), the partition values
+    // should be empty list.
+    if (partitionPath.isEmpty()) {
+      return Collections.emptyList();
+    }
     String[] splits = partitionPath.split("/");
     return Arrays.stream(splits).map(s -> {
       if (s.contains("=")) {

hudi-sync/hudi-hive-sync/src/test/java/org/apache/hudi/hive/TestMultiPartKeysValueExtractor.java

@@ -0,0 +1,41 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.hudi.hive;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class TestMultiPartKeysValueExtractor {
+
+  @Test
+  public void testMultiPartExtractor() {
+    MultiPartKeysValueExtractor valueExtractor = new MultiPartKeysValueExtractor();
+    // Test extract empty partitionPath
+    assertEquals(new ArrayList<>(), valueExtractor.extractPartitionValuesInPath(""));
+    List<String> expected = new ArrayList<>();
+    expected.add("2021-04-25");
+    expected.add("04");
+    // Test extract multi-partition path
+    assertEquals(expected, valueExtractor.extractPartitionValuesInPath("2021-04-25/04"));
+    // Test extract hive style partition path
+    assertEquals(expected, valueExtractor.extractPartitionValuesInPath("ds=2021-04-25/hh=04"));
+  }
+}