public SimplifySpanBuild appendSpecialUnitToFirst(BaseSpecialUnit specialUnit){
  if (null == specialUnit)   return this;
  String specialText=specialUnit.getSpecialText();
  if (TextUtils.isEmpty(specialText))   return this;
  int curBeforeFirstPos=mBeforeStringBuilder.length();
  specialUnit.setStartPoss(new int[]{curBeforeFirstPos});
  mBeforeStringBuilder.insert(curBeforeFirstPos,specialText);
  mBeforeSpecialUnit.add(specialUnit);
  return this;
}

public SimplifySpanBuild appendSpecialUnitToFirst ( BaseSpecialUnit specialUnit ) { if ( null == specialUnit ) return this ; String specialText = specialUnit . getSpecialText ( ) ; if ( TextUtils . isEmpty ( specialText ) ) return this ; int curBeforeFirstPos = mBeforeStringBuilder . length ( ) ; specialUnit . setStartPoss ( new int [ ] { curBeforeFirstPos } ) ; mBeforeStringBuilder . insert ( curBeforeFirstPos , specialText ) ; mBeforeSpecialUnit . add ( specialUnit ) ; return this ; }
append specialunit to first ( behind the existing beforecontent )
