### Question:
OMVolumeSetOwnerRequest extends OMVolumeRequest { @Override public OMRequest preExecute(OzoneManager ozoneManager) throws IOException { long modificationTime = Time.now(); SetVolumePropertyRequest modifiedRequest = getOmRequest() .getSetVolumePropertyRequest().toBuilder() .setModificationTime(modificationTime).build(); return getOmRequest().toBuilder() .setSetVolumePropertyRequest(modifiedRequest.toBuilder()) .setUserInfo(getUserInfo()) .build(); } OMVolumeSetOwnerRequest(OMRequest omRequest); @Override OMRequest preExecute(OzoneManager ozoneManager); @Override OMClientResponse validateAndUpdateCache(OzoneManager ozoneManager,
      long transactionLogIndex,
      OzoneManagerDoubleBufferHelper ozoneManagerDoubleBufferHelper);  }### Answer:
@Test public void testPreExecute() throws Exception { String volumeName = UUID.randomUUID().toString(); String newOwner = "user1"; OMRequest originalRequest = TestOMRequestUtils.createSetVolumePropertyRequest(volumeName, newOwner); OMVolumeSetQuotaRequest omVolumeSetQuotaRequest = new OMVolumeSetQuotaRequest(originalRequest); OMRequest modifiedRequest = omVolumeSetQuotaRequest.preExecute( ozoneManager); Assert.assertNotEquals(modifiedRequest, originalRequest); }