code: @Test public void deleteFileTest() throws IOException {
    List<ClientWorkerInfo> workers=mTfs.getWorkersInfo();
    Assert.assertEquals(1,workers.size());
    Assert.assertEquals(WORKER_CAPACITY_BYTES,workers.get(0).getCapacityBytes());
    Assert.assertEquals(0,workers.get(0).getUsedBytes());
    int writeBytes=USER_QUOTA_UNIT_BYTES * 2;
    for (int k=0; k < 5; k++) {
      int fileId=TestUtils.createByteFile(mTfs,"/file" + k,WriteType.MUST_CACHE,writeBytes);
      TachyonFile file=mTfs.getFile(fileId);
      Assert.assertTrue(file.isInMemory());
      Assert.assertTrue(mTfs.exist("/file" + k));
      workers=mTfs.getWorkersInfo();
      Assert.assertEquals(1,workers.size());
      Assert.assertEquals(WORKER_CAPACITY_BYTES,workers.get(0).getCapacityBytes());
      Assert.assertEquals(writeBytes * (k + 1),workers.get(0).getUsedBytes());
    }
    for (int k=0; k < 5; k++) {
      int fileId=mTfs.getFileId("/file" + k);
      mTfs.delete(fileId,true);
      Assert.assertFalse(mTfs.exist("/file" + k));
      CommonUtils.sleepMs(null,SLEEP_MS);
      workers=mTfs.getWorkersInfo();
      Assert.assertEquals(1,workers.size());
      Assert.assertEquals(WORKER_CAPACITY_BYTES,workers.get(0).getCapacityBytes());
      Assert.assertEquals(writeBytes * (4 - k),workers.get(0).getUsedBytes());
    }
  }
  