[I] [Java] Should ListVector.reset() reset the position(index)? [arrow-java]

[via GitHub]

lfygh opened a new issue, #205:
URL: https://github.com/apache/arrow-java/issues/205

   
   ```java
   RootAllocator rootAllocator = new RootAllocator();
           ListVector identity = ListVector.empty("identity", rootAllocator);
           VectorSchemaRoot root = new VectorSchemaRoot(List.of(identity));
           root.allocateNew();
   
           UnionListWriter writer = identity.getWriter();
   
           byte[] bytes1 = "hello1".getBytes(StandardCharsets.UTF_8);
           ArrowBuf buffer = rootAllocator.buffer(bytes1.length);
           buffer.setBytes(0,bytes1);
           writer.startList();
           writer.varChar().writeVarChar(0,bytes1.length,buffer);
           writer.endList();
           root.setRowCount(1);
           System.out.println(root.contentToTSVString());
           
           root.getFieldVectors().forEach(ValueVector::reset);   //reset 
fieldVector
   
           byte[] bytes2 = "hello2".getBytes(StandardCharsets.UTF_8);
           buffer.setBytes(0,bytes2);
           writer.startList();
           writer.varChar().writeVarChar(0,bytes2.length,buffer);
           writer.endList();
   
           root.setRowCount(1);
           System.out.println(root.contentToTSVString());
   ```
   
   the result is
   ```
   identity
   ["hello1"]
   
   identity
   null
   ```
   
   The above results are confusing。 
   
   The correct way is using the `writer.setPosition(index)`,
   
   I don't know if it's a bug or other something.
   
   ### Component(s)
   
   Java


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