优化 tree 泛型

This commit is contained in:
如梦技术 2018-12-27 11:29:51 +08:00
parent d40e743be9
commit a9dcbaacec
2 changed files with 52 additions and 47 deletions

View File

@ -23,40 +23,45 @@ import java.util.List;
*
* @author zhuangqian
*/
public class ForestNodeManager {
public class ForestNodeManager<T extends INode> {
private List<INode> list;// 森林的所有节点
/**
* 森林的所有节点
*/
private List<T> list;
public ForestNodeManager(List<INode> items) {
list = items;
}
public ForestNodeManager(List<T> items) {
list = items;
}
/**
* 根据节点ID获取一个节点
*
* @param id 节点ID
* @return 对应的节点对象
*/
public INode getTreeNodeAT(int id) {
for (INode forestNode : list) {
if (forestNode.getId() == id)
return forestNode;
}
return null;
}
/**
* 根据节点ID获取一个节点
*
* @param id 节点ID
* @return 对应的节点对象
*/
public INode getTreeNodeAT(int id) {
for (INode forestNode : list) {
if (forestNode.getId() == id) {
return forestNode;
}
}
return null;
}
/**
* 获取树的根节点(一个森林对应多颗树)
*
* @return 树的根节点集合
*/
public List<INode> getRoot() {
List<INode> roots = new ArrayList<>();
for (INode forestNode : list) {
if (forestNode.getParentId() == 0)
roots.add(forestNode);
}
return roots;
}
/**
* 获取树的根节点(一个森林对应多颗树)
*
* @return 树的根节点集合
*/
public List<T> getRoot() {
List<T> roots = new ArrayList<>();
for (T forestNode : list) {
if (forestNode.getParentId() == 0) {
roots.add(forestNode);
}
}
return roots;
}
}

View File

@ -24,22 +24,22 @@ import java.util.List;
*/
public class ForestNodeMerger {
/**
* 将节点数组归并为一个森林多棵树填充节点的children域
* 时间复杂度为O(n^2)
*
* @param items 节点域
* @return 多棵树的根节点集合
*/
public static List<INode> merge(List<INode> items) {
ForestNodeManager forestNodeManager = new ForestNodeManager(items);
for (INode forestNode : items) {
if (forestNode.getParentId() != 0) {
INode node = forestNodeManager.getTreeNodeAT(forestNode.getParentId());
/**
* 将节点数组归并为一个森林多棵树填充节点的children域
* 时间复杂度为O(n^2)
*
* @param items 节点域
* @return 多棵树的根节点集合
*/
public static <T extends INode> List<T> merge(List<T> items) {
ForestNodeManager<T> forestNodeManager = new ForestNodeManager<>(items);
for (T forestNode : items) {
if (forestNode.getParentId() != 0) {
INode node = forestNodeManager.getTreeNodeAT(forestNode.getParentId());
node.getChildren().add(forestNode);
}
}
return forestNodeManager.getRoot();
}
}
}
return forestNodeManager.getRoot();
}
}