/** Test toStrings */
 @Test
 public void testToString() {
   final String expectedLinear = "TmfTimestampTransformLinearFast [ slope = 314.0, offset = 0.0 ]";
   final String expectedLinearBigDec =
       "TmfTimestampTransformLinearFast [ slope = 314, offset = 0 ]";
   final String expectedOffset = "TmfConstantTransform [ offset = 314 ]";
   final String expectedIdentity = "TmfTimestampTransform [ IDENTITY ]";
   final String expectedOffset100 = "TmfConstantTransform [ offset = 100 ]";
   assertEquals(expectedLinear, TimestampTransformFactory.createLinear(314, 0).toString());
   assertEquals(
       expectedLinearBigDec,
       TimestampTransformFactory.createLinear(
               NonNullUtils.checkNotNull(BigDecimal.valueOf(314)),
               NonNullUtils.checkNotNull(BigDecimal.ZERO))
           .toString());
   assertEquals(expectedOffset, TimestampTransformFactory.createLinear(1, 314).toString());
   assertEquals(expectedOffset, TimestampTransformFactory.createWithOffset(314).toString());
   assertEquals(
       expectedOffset,
       TimestampTransformFactory.createWithOffset(14)
           .composeWith(TimestampTransformFactory.createWithOffset(300))
           .toString());
   assertEquals(
       expectedIdentity,
       TimestampTransformFactory.createWithOffset(314)
           .composeWith(TimestampTransformFactory.createWithOffset(-314))
           .toString());
   assertEquals(expectedIdentity, TimestampTransformFactory.createWithOffset(0).toString());
   assertEquals(expectedIdentity, identity1.toString());
   assertEquals(expectedOffset100, offset1.toString());
   assertEquals(expectedOffset100, offset2.toString());
   assertEquals(expectedOffset100, offset3.toString());
   assertEquals(expectedOffset100, offset4.toString());
 }