返回一个树形结构数据

package com.llcbk;


import org.springframework.beans.BeanUtils;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;


public class NodeTest {
    public static void main(String[]args){
        //准备数据
        List testNodeList = new ArrayList<>();
        TestNode node1 = new TestNode(1,0,"父节点1");
        TestNode node2 = new TestNode(2,1,"子节点");
        TestNode node3 = new TestNode(3,2,"子节点1.2");
        TestNode node4 = new TestNode(4,0,"父节点2");
        TestNode node5 = new TestNode(5,4,"子节点2.2");

        //将数据存储到集合中
        testNodeList.add(node1);
        testNodeList.add(node2);
        testNodeList.add(node3);
        testNodeList.add(node4);
        testNodeList.add(node5);
        List bosUserVos = nodeDataToTree(testNodeList).get(String.valueOf(0)).getChildren();
        System.out.println("数据为："+bosUserVos);
    }

    public static Map nodeDataToTree(List list) {
        String[] matchs = new String[list.size()];
        String id;
        String parentId;
        int i = 0;
        Map map = new HashMap<>();
        map.put(String.valueOf(0), new TestNodeVo());
        map.get(String.valueOf(0)).setChildren(new ArrayList<>());
        for (TestNode p : list) {
            TestNodeVo vo = new TestNodeVo();
            BeanUtils.copyProperties(p, vo);
            map.put(String.valueOf(vo.getId()), vo);
            if (vo.getChildren() == null) {
                vo.setChildren(new ArrayList());
            }
            if (vo.getParentId() == null || "".equals(vo.getParentId())) {
                vo.setParentId(0);
            }
            matchs[i++] = vo.getId() + ":" + vo.getParentId();
        }
        for (String match : matchs) {
            id = match.split(":")[0];
            parentId = match.split(":")[1];
            if (null != map.get(parentId)) {
                if (null == map.get(parentId).getChildren()) {
                    map.get(parentId).setChildren(new ArrayList<>());
                }
                map.get(parentId).getChildren().add(map.get(id));
            }
        }
        return map;
    }
}

package com.llcbk;

import io.swagger.annotations.ApiModelProperty;


public class TestNode  {
    @ApiModelProperty(value = "序号")
    private Integer id;
    @ApiModelProperty(value = "父节点")
    private Integer parentId;
    @ApiModelProperty(value = "节点名称")
    private String nodeName;

    public TestNode() {
    }

    public TestNode(Integer id, Integer parentId, String nodeName) {
        this.id = id;
        this.parentId = parentId;
        this.nodeName = nodeName;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public Integer getParentId() {
        return parentId;
    }

    public void setParentId(Integer parentId) {
        this.parentId = parentId;
    }

    public String getNodeName() {
        return nodeName;
    }

    public void setNodeName(String nodeName) {
        this.nodeName = nodeName;
    }




    @Override
    public String toString() {
        return "TestNode{" +
                " + id +
                ", parentId=" + parentId +
                ", nodeName='" + nodeName + ''' +
                '}';


    }
}

package com.llcbk;


import java.util.List;


public class TestNodeVo extends TestNode {

    private List children;

    public List getChildren() {
        return children;
    }

    public void setChildren(List children) {
        this.children = children;
    }
}

断点结果展示