Return a tree structure data

Return a tree structure data

1、 Data structure display

2、 Text

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){
    
        // Prepare the data 
        List<TestNode> testNodeList = new ArrayList<>();
        TestNode node1 = new TestNode(1,0," Parent node 1");
        TestNode node2 = new TestNode(2,1," Child node ");
        TestNode node3 = new TestNode(3,2," Child node 1.2");
        TestNode node4 = new TestNode(4,0," Parent node 2");
        TestNode node5 = new TestNode(5,4," Child node 2.2");

        // Store data in a collection 
        testNodeList.add(node1);
        testNodeList.add(node2);
        testNodeList.add(node3);
        testNodeList.add(node4);
        testNodeList.add(node5);
        List<TestNodeVo> bosUserVos = nodeDataToTree(testNodeList).get(String.valueOf(0)).getChildren();
        System.out.println(" The data is ："+bosUserVos);
    }

    public static Map<String, TestNodeVo> nodeDataToTree(List<TestNode> list) {
    
        String[] matchs = new String[list.size()];
        String id;
        String parentId;
        int i = 0;
        Map<String, TestNodeVo> 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<TestNodeVo>());
            }
            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;

/** *  node （ Used to generate tree relationships ） */
public class TestNode  {
    
    @ApiModelProperty(value = " Serial number ")
    private Integer id;
    @ApiModelProperty(value = " Parent node ")
    private Integer parentId;
    @ApiModelProperty(value = " The name of the node ")
    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=" + id +
                ", parentId=" + parentId +
                ", nodeName='" + nodeName + '\'' +
                '}';


    }
}

package com.llcbk;


import java.util.List;


public class TestNodeVo extends TestNode {
    

    private List<TestNodeVo> children;

    public List<TestNodeVo> getChildren() {
    
        return children;
    }

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

Breakpoint result display