工作中碰到了树形结构的一些需求

1. 提供节点为null值的存储
2. 提供父节点的引用,且更新子节点时父节点所持有的子节点引用同步更新
3. 提供查询当前节点所处高度,父节点所处高度
4. 即时挂载父节点,更改父节点时,同步更新父节点的父节点引用信息,以及父节点的子节点引用信息
5. 类似双向链表,对父项和子项信息的同步更新进行null值考虑,并对多线程操作时考虑一些节点拥有的属性的并发安全性问题
6. 后续有需要会更新优化,如果有写的欠缺的地方,请读者在评论处指出

package com.ygsoft.gris.enw.csd.special.impl.util;import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.atomic.AtomicInteger;import org.springframework.util.CollectionUtils;public class CommonNode<T> {private T data;private CommonNode<T> parentNode;private AtomicInteger currentNodeHeight;private AtomicInteger parentNodeHeight;private List<CommonNode<T>> childCommonNodes;private <T> CommonNode() {}/*** 无父节点构造方法* * @param data*/public CommonNode(final T data) {if (data != null) {this.setData(data);}this.currentNodeHeight = new AtomicInteger(0);this.parentNodeHeight = new AtomicInteger(-1);}/*** 带父节点构造方法* * @param data* @param parentNode*/public CommonNode(final T data, final CommonNode<T> parentNode) {if (data != null) {this.setData(data);}if (parentNode != null) {this.setParentNode(parentNode);} else {this.currentNodeHeight = new AtomicInteger(0);this.parentNodeHeight = new AtomicInteger(-1);}}public void setData(final T data) {this.data = data;}public T getData() {return data;}public void setParentNode(final CommonNode<T> parentNode) {// 之前连接的如果有父节点,需要把父节点中持有的引用删掉CommonNode<T> beforeAddParentNode = this.getParentNode();if (beforeAddParentNode != null) {List<CommonNode<T>> beforeAddChildCommonNodes = beforeAddParentNode.getChildCommonNodes();if (!CollectionUtils.isEmpty(beforeAddChildCommonNodes)) {beforeAddChildCommonNodes.remove(this);}} else {List<CommonNode<T>> curCommonNodes = parentNode.getChildCommonNodes();if (curCommonNodes == null) {curCommonNodes = new CopyOnWriteArrayList<>();parentNode.setChildCommonNodes(curCommonNodes);}curCommonNodes.add(this);}this.parentNode = parentNode;this.parentNodeHeight = parentNode.getCurrentNodeHeight();this.currentNodeHeight = new AtomicInteger(parentNode.getCurrentNodeHeight().get()+1);}public AtomicInteger getCurrentNodeHeight() {return currentNodeHeight;}private void setCurrentNodeHeight(final AtomicInteger newCurrentNodeHeight) {currentNodeHeight = newCurrentNodeHeight;}public CommonNode<T> getParentNode() {return parentNode;}public AtomicInteger getParentNodeHeight() {return parentNodeHeight;}private void setParentNodeHeight(final AtomicInteger newParentNodeHeight) {parentNodeHeight = newParentNodeHeight;}public List<CommonNode<T>> getChildCommonNodes() {return childCommonNodes;}public void setChildCommonNodes(final List<CommonNode<T>> newChildCommonNodes) {childCommonNodes = newChildCommonNodes;}
}