自定义tree工具类 TreeUtils.java

自定义tree工具类 TreeUtils.java

简介

• 自定义tree工具类

api

• 将参数list 构造成 tree *getTree(List list);*

源码

• import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  import java.util.stream.Collectors;
   
  /**
   * @说明：tree工具类
   */
  public class TreeUtils {
  	
  	/**
  	 * 方法功能说明：@1.将参数list 构造成 tree
  	 */
      public static List getTree(List list) {
      	Collections.sort(list);
          Map> son = list.stream().filter(node -> !"0".equals(node.getParentId()))
          		.collect(Collectors.groupingBy(node -> node.getParentId()));
          list.forEach(node -> node.setChildList(son.get(node.getNodeId())));
          return list.stream().filter(node -> "0".equals(node.getParentId())).collect(Collectors.toList());
      }
  	
  	/**
  	 * @说明：tree节点
  	 */
  	public class Node implements Comparable {
  		
  		private String nodeId;
  		private String nodeName;
  		private String parentId;
  		private Long sort;
  		
  		public Long getSort() {
  			return sort;
  		}
  		public void setSort(Long sort) {
  			this.sort = sort;
  		}
  		public String getNodeId() {
  			return nodeId;
  		}
  		public void setNodeId(String nodeId) {
  			this.nodeId = nodeId;
  		}
  		public String getNodeName() {
  			return nodeName;
  		}
  		public void setNodeName(String nodeName) {
  			this.nodeName = nodeName;
  		}
  		public String getParentId() {
  			return parentId;
  		}
  		public void setParentId(String parentId) {
  			this.parentId = parentId;
  		}
  		
  		public Node(String nodeId, String nodeName, String parentId, Long sort) {
  			this.nodeId = nodeId;
  			this.nodeName = nodeName;
  			this.parentId = parentId;
  			this.sort = sort;
  		}
  		
  		@Override
  		public boolean equals(Object obj) {
  			if (this == obj) { return true; }
  			if (obj == null) { return false; }
  			if (getClass() != obj.getClass()) { return false; }
  			Node other = (Node) obj;
  			if (nodeId == null) {
  				if (other.nodeId != null) { return false; }
  			} else if (!nodeId.equals(other.nodeId)) {
  				return false;
  			}
  			if (nodeName == null) {
  				if (other.nodeName != null) { return false; }
  			} else if (!nodeName.equals(other.nodeName)) {
  				return false;
  			}
  			if (parentId == null) {
  				if (other.parentId != null) { return false; }
  			} else if (!parentId.equals(other.parentId)) {
  				return false;
  			}
  			if (sort == null) {
  				if (other.sort != null) { return false; }
  			} else if (!sort.equals(other.sort)) {
  				return false;
  			}
  			return true;
  		}
   
  		/**
  		 * 下级节点集合
  		 */
  		private List childList;
   
  		public List getChildList() {
  			return childList;
  		}
  		public void setChildList(List childList) {
  			this.childList = childList;
  		}
  		@Override
  		public int compareTo(Node node) {
  			//正序
  			return this.sort.compareTo(node.sort);
  			//倒序
  //			return node.sort.compareTo(this.sort);
  		}
  	}
  	
  }