java.time.LocalDateTime.minusDays(long daysToSubtract)

package com.codingdict;

import java.time.LocalDateTime;
import java.time.Period;

public class LocalDateTimeDemo {
   public static void main(String[] args) {

      LocalDateTime date = LocalDateTime.parse("2017-02-03T12:30:30");
      System.out.println(date.minus(Period.ofDays(2)));  
   }
}