for (int i = 0; i < newdt.size(); i++) {
for (int j = newdt.size() - 1; j > i; j--) {
String one = newdt.get(i).getTask_id();
String two = newdt.get(j).getTask_id();
if (two.equals(one)) {
newdt.remove(j);
}
}
}原文：https://www.cnblogs.com/Darkqueen/p/11006301.html