插入区间

/**
* Definition of Interval:
* public classs Interval {
*     int start, end;
*     Interval(int start, int end) {
*         this.start = start;
*         this.end = end;
*     }
*/

class Solution {
/**
* Insert newInterval into intervals.
* @param intervals: Sorted interval list.
* @param newInterval: A new interval.
* @return: A new sorted interval list.
*/
public ArrayList<Interval> insert(ArrayList<Interval> intervals, Interval newInterval) {
// write your code here
if(intervals == null || newInterval == null ){
return intervals;
}
if(intervals.size()==0){
intervals.add(newInterval);
return intervals;
}
ListIterator<Interval>  it = intervals.listIterator();
while(it.hasNext()){
Interval temInterval = it.next();
if(newInterval.end < temInterval.start){
it.previous();
it.add(newInterval);
return intervals;
}else{
if(temInterval.end<newInterval.start){
continue;
}else{
newInterval.start = Math.min(temInterval.start,newInterval.start);
newInterval.end  =  Math.max(temInterval.end,newInterval.end);
it.remove();
}
}
}
intervals.add(newInterval);
return intervals;
}
}