java比较两个集合并删除常用项
我有两个集合,其中包含一些元素作为对象。我想从集合中删除公共元素。如何从集合中删除公共元素
Set<AcceptorInventory> updateList = new HashSet<AcceptorInventory>();
Set<AcceptorInventory> saveList = new HashSet<AcceptorInventory>();
两组都有一些项目,saveList
有重复的项目&;我希望从saveList
中删除重复的项目。我尝试了foreach
循环,但没有成功
样本输出:
save 5
save 20
save 50
save 10
update 5
update 10
update 20
AcceptorInventory哈希代码和equals
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + count;
result = prime * result
+ ((currency == null) ? 0 : currency.hashCode());
result = prime * result + ((date == null) ? 0 : date.hashCode());
result = prime * result + (int) (id ^ (id >>> 32));
result = prime * result + (isCleared ? 1231 : 1237);
result = prime * result
+ ((kioskMachine == null) ? 0 : kioskMachine.hashCode());
result = prime * result + ((time == null) ? 0 : time.hashCode());
long temp;
temp = Double.doubleToLongBits(total);
result = prime * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
AcceptorInventory other = (AcceptorInventory) obj;
if (count != other.count)
return false;
if (currency == null) {
if (other.currency != null)
return false;
} else if (!currency.equals(other.currency))
return false;
if (date == null) {
if (other.date != null)
return false;
} else if (!date.equals(other.date))
return false;
if (id != other.id)
return false;
if (isCleared != other.isCleared)
return false;
if (kioskMachine == null) {
if (other.kioskMachine != null)
return false;
} else if (!kioskMachine.equals(other.kioskMachine))
return false;
if (time == null) {
if (other.time != null)
return false;
} else if (!time.equals(other.time))
return false;
if (Double.doubleToLongBits(total) != Double
.doubleToLongBits(other.total))
return false;
return true;
}
# 1 楼答案
将从
updateList
中删除saveList
的所有元素如果还想从
saveList
中删除updateList
的元素,则必须先创建其中一个集合的副本:请注意,为了使
AcceptorInventory
作为HashSet
的元素正常工作,它必须覆盖equals
和hashCode
方法,任何两个相等的AcceptorInventory
都必须具有相同的hashCode
# 2 楼答案
您可以使用从当前存储列表中删除常用项