question: @ Override public boolean markNextSequence ( ) throws IOException { if ( mSeqSize < mLimit && mPointerSize + mPointerEntrySize <= mLimit ) { mPointers . writeByte ( ( int ) mChecksumSeq . getValue ( ) ) ; mChecksumSeq . reset ( ) ; if ( mChecksumQual != null ) { mPointers . writeByte ( ( int ) mChecksumQual . getValue ( ) ) ; mChecksumQual . reset ( ) ; } mPointers . writeInt ( ( int ) mSeqSize ) ; mPointerSize += mPointerEntrySize ; return true ; } return false ; }
target:  Declares the beginning of a sequence.