public void append(RollupEvent rollup) throws IOException {
        ensureOpen();
        outputStream.write(serializer.toBytes(rollup));
        outputStream.write('\n');
        outputStream.flush();
    }
public void append(RollupEvent rollup) throws IOException {
        ensureOpen();
        outputStream.write(serializer.toBytes(rollup));
        outputStream.write('\n');
        outputStream.flush();
    }
public void append ( RollupEvent rollup ) throws IOException { ensureOpen ( ) ; outputStream . write ( serializer . toBytes ( rollup ) ) ; outputStream . write ( ' ' ) ; outputStream . flush ( ) ; }
Serialize a Rollup Event and append it to the file.

@param rollup The rollup to append.
@throws IOException
Serialize a Rollup Event and append it to the file .