question: public SequencesWriter ( SequenceDataSource source , File outputDir , long sizeLimit , Collection < String > namesToExclude , PrereadType type , boolean compressed , Integer trimQualityThreshold ) { mDataSource = source ; mOutputDir = outputDir ; mPrereadType = type ; mSdfId = new SdfId ( ) ; if ( mDataSource == null ) { throw new NullPointerException ( "Provided data source was null." ) ; } FileUtils . ensureOutputDirectory ( mOutputDir ) ; mSizeLimit = sizeLimit ; mNamesToExclude = namesToExclude == null ? new ArrayList < > ( ) : namesToExclude ; mCompressed = compressed ; if ( trimQualityThreshold != null ) { if ( System . getProperty ( "quality-window-size" ) != null ) { final int windowSize = Integer . parseInt ( System . getProperty ( "quality-window-size" ) ) ; mReadTrimmer = new DefaultReadTrimmer ( windowSize , trimQualityThreshold ) ; Diagnostic . userLog ( "Performing trimming with quality threshold " + trimQualityThreshold + " window size " + windowSize ) ; } else { mReadTrimmer = new BestSumReadTrimmer ( trimQualityThreshold ) ; Diagnostic . userLog ( "Performing trimming with BestSum, threshold " + trimQualityThreshold ) ; } } else { mReadTrimmer = new NullReadTrimmer ( ) ; } }
target:  Creates a writer for processing sequences from provided data source.