list集合均分n个集合的两种方法

/**

* 将一个list均分成n个list,主要通过偏移量来实现的

*

* @param

* @return

*/

public static List>createList(List targe, int size) {

List> listArr =new ArrayList>();

    //获取被拆分的数组个数

    int arrSize = targe.size() % size ==0 ? targe.size() / size : targe.size() / size +1;

    for (int i =0; i < arrSize; i++) {

List sub =new ArrayList();

        //把指定索引数据放入到list中

        for (int j = i * size; j <= size * (i +1) -1; j++) {

if (j <= targe.size() -1) {

sub.add(targe.get(j));

            }

}

listArr.add(sub);

    }

return listArr;

}

public static List>averageAssign(List source, int n) {

List> result =new ArrayList>();

    int remaider = source.size() % n;  //(先计算出余数)

    int number = source.size() / n;  //然后是商

    int offset =0;//偏移量

    for (int i =0; i < n; i++) {

List value =null;

        if (remaider >0) {

value = source.subList(i * number + offset, (i +1) * number + offset +1);

            remaider--;

            offset++;

        }else {

value = source.subList(i * number + offset, (i +1) * number + offset);

        }

result.add(value);

    }

return result;

}