我保持Node对象在一个TreeSet:TreeSet包含/删除不工作?
public TreeSet<Node> viewNodes = new TreeSet<Node>();
节点看起来是这样的:
public class Node implements Comparable<Node>{
private long nodeID;
...
public long getID() {
return nodeID;
}
@Override
public int compareTo(Node n) {
System.out.println("comparing: " +this + " with " + n + " -- " + new Long(nodeID).compareTo(n.getID()));
return new Long(nodeID).compareTo(n.getID());
}
@Override
public boolean equals(Object o){
if(o instanceof Node){
System.out.println((compareTo((Node)o) == 0));
return compareTo((Node)o) == 0;
}
return false;
}
@Override
public int hashCode(){
return new Long(nodeID).hashCode();
}
}
然而,当我尝试删除节点,他们没有得到去除,TreeSet的认为他们不在集合中!
删除代码:
System.out.println("removing " + node);
System.out.println("viewNodes: " + viewNodes);
System.out.println("contains node?: " + viewNodes.contains(node));
viewNodes.remove(node);
System.out.println("now viewNodes looks like: " +viewNodes);
输出:
removing 5
viewNodes: [5, 4, 3, 2, 1]
comparing: 5 with 2 -- 1
comparing: 5 with 1 -- 1
contains node?: false
comparing: 5 with 2 -- 1
comparing: 5 with 1 -- 1
now viewNodes looks like: [5, 4, 3, 2, 1]
这是为什么?我已经实现了Comparable,应该不是吗?
请显示一个小程序来演示问题。这个对我有用。 – 2015-04-04 22:18:20
检查删除操作的结果。另请参阅包含()在预期删除后说的内容。你确认_node_被插入到容器中了吗?注意到你的输出说节点不包含这可能解释你看到的结果。 – bvj 2015-04-04 22:23:07
将ID插入TreeSet后,我改变了它的值!它现在有用,谢谢你安迪!作为回答发布了 – Casey 2015-04-04 22:28:01