public ArrowBuf newArrowBuf(int offset,int length,BufferManager manager){
  allocator.assertOpen();
  final ArrowBuf buf=new ArrowBuf(bufRefCnt,this,underlying,manager,allocator.getAsByteBufAllocator(),offset,length,false);
  if (BaseAllocator.DEBUG) {
    historicalLog.recordEvent("ArrowBuf(BufferLedger, BufferAllocator[%s], UnsafeDirectLittleEndian[identityHashCode == " + "%d](%s)) => ledger hc == %d",allocator.name,System.identityHashCode(buf),buf.toString(),System.identityHashCode(this));
synchronized (buffers) {
      buffers.put(buf,null);
    }
  }
  return buf;
}

public ArrowBuf newArrowBuf ( int offset , int length , BufferManager manager ) { allocator . assertOpen ( ) ; final ArrowBuf buf = new ArrowBuf ( bufRefCnt , this , underlying , manager , allocator . getAsByteBufAllocator ( ) , offset , length , false ) ; if ( BaseAllocator . DEBUG ) { historicalLog . recordEvent ( "ArrowBuf(BufferLedger, BufferAllocator[%s], UnsafeDirectLittleEndian[identityHashCode == " + "%d](%s)) => ledger hc == %d" , allocator . name , System . identityHashCode ( buf ) , buf . toString ( ) , System . identityHashCode ( this ) ) ; synchronized ( buffers ) { buffers . put ( buf , null ) ; } } return buf ; }
create a new arrowbuf associated with this allocationmanager and memory .
