大集合转为小集合

public static <T> List<List<T>> split(List<T> srcList, int groupSize) {
int mod = srcList.size() % groupSize;
int pou = srcList.size() / groupSize;
int len = (mod == 0 ? pou : pou + 1);
int n = 0;
int start;

List<T> list = null;
List<List<T>> rlist = new ArrayList<List<T>>();

for (int i = 0; i < len; i++) {
if(i == pou) {
n = mod;
} else {
n = groupSize;
}
list = new ArrayList<T>(n);
start = i * groupSize;
for (int k = 0; k < n; k++) {
list.add(srcList.get(start + k));
}
rlist.add(list);
}
return rlist;
}