public void setEntryPosition(final long walFileVersionId, final long position) {
    this.walEntryPosition.setEntryPosition(walFileVersionId, position, value);
    this.value = null;
    synchronized (this) {
      this.notifyAll();
    }
  }
Get this handler's value.

@throws WALPipeException when failing to get the value.
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/storageengine/dataregion/wal/utils/WALEntryHandler.java