### Question:
Helper { public static double round( double value, int exponent ) { double factor = Math.pow(10, exponent); return Math.round(value * factor) / factor; } private  Helper(); static ArrayList<Integer> tIntListToArrayList( TIntList from ); static Locale getLocale( String param ); static int countBitValue( int maxTurnCosts ); static void loadProperties( Map<String, String> map, Reader tmpReader ); static void saveProperties( Map<String, String> map, Writer tmpWriter ); static List<String> readFile( String file ); static List<String> readFile( Reader simpleReader ); static String isToString( InputStream inputStream ); static int idealIntArraySize( int need ); static int idealByteArraySize( int need ); static boolean removeDir( File file ); static long getTotalMB(); static long getUsedMB(); static String getMemInfo(); static int getSizeOfObjectRef( int factor ); static int getSizeOfLongArray( int length, int factor ); static int getSizeOfObjectArray( int length, int factor ); static void close( Closeable cl ); static boolean isEmpty( String str ); static boolean isFileMapped( ByteBuffer bb ); static int calcIndexSize( BBox graphBounds ); static String pruneFileEnd( String file ); static TIntList createTList( int... list ); static PointList createPointList( double... list ); static PointList createPointList3D( double... list ); static final int degreeToInt( double deg ); static final double intToDegree( int storedInt ); static final int eleToInt( double ele ); static final double intToEle( int integEle ); static void cleanMappedByteBuffer( final ByteBuffer buffer ); static void cleanHack(); static String nf( long no ); static String firstBig( String sayText ); static final double keepIn( double value, double min, double max ); static double round( double value, int exponent ); static final double round6( double value ); static final double round4( double value ); static final double round2( double value ); static final DistanceCalc DIST_EARTH; static final DistanceCalc3D DIST_3D; static final DistancePlaneProjection DIST_PLANE; static Charset UTF_CS; static final long MB; }### Answer:
@Test public void testRound() { assertEquals(100.94, Helper.round(100.94, 2), 1e-7); assertEquals(100.9, Helper.round(100.94, 1), 1e-7); assertEquals(101.0, Helper.round(100.95, 1), 1e-7); }