core/src/main/java/com/orientechnologies/common/collection/closabledictionary/OClosableLinkedContainer.java
public void clear() {
    lruLock.lock();
    try {
      data.clear();
      openFiles.set(0);

      for (int n = 0; n < NUMBER_OF_READ_BUFFERS; n++) {
        final AtomicReference<OClosableEntry<K, V>>[] buffer = readBuffers[n];
        for (int i = 0; i < READ_BUFFER_SIZE; i++) {
          buffer[i].set(null);
        }

        readBufferReadCount[n] = 0;
        readBufferWriteCount[n].set(0);
        readBufferDrainAtWriteCount[n].set(0);
      }

      stateBuffer.clear();

      while (lruList.poll() != null)
        ;
    } finally {
      lruLock.unlock();
    }
  }
public void clear() {
    lruLock.lock();
    try {
      data.clear();
      openFiles.set(0);

      for (int n = 0; n < NUMBER_OF_READ_BUFFERS; n++) {
        final AtomicReference<OClosableEntry<K, V>>[] buffer = readBuffers[n];
        for (int i = 0; i < READ_BUFFER_SIZE; i++) {
          buffer[i].set(null);
        }

        readBufferReadCount[n] = 0;
        readBufferWriteCount[n].set(0);
        readBufferDrainAtWriteCount[n].set(0);
      }

      stateBuffer.clear();

      while (lruList.poll() != null)
        ;
    } finally {
      lruLock.unlock();
    }
  }
Clears all content.