masyarakat Belajar Perpustakaan Alatan Masa lapang
cari
Melayu
Rumah > Java > javaTutorial > teks badan

JAVA 根据数据库表内容生产树结构JSON数据的实例代码

高洛峰
Lepaskan： 2017-01-17 13:39:50
asal
1316 orang telah melayarinya

1、利用场景

　　组织机构树，通常会有组织机构表，其中有code(代码),pcode(上级代码),name(组织名称)等字段

2、构造数据（以下数据并不是组织机构数据，而纯属本人胡编乱造的数据）

List<Tree<Test>> trees = new ArrayList<Tree<Test>>();
tests.add(new Test("0", "", "关于本人"));
tests.add(new Test("1", "0", "技术学习"));
tests.add(new Test("2", "0", "兴趣"));
tests.add(new Test("3", "1", "JAVA"));
tests.add(new Test("4", "1", "oracle"));
tests.add(new Test("5", "1", "spring"));
tests.add(new Test("6", "1", "springmvc"));
tests.add(new Test("7", "1", "fastdfs"));
tests.add(new Test("8", "1", "linux"));
tests.add(new Test("9", "2", "骑行"));
tests.add(new Test("10", "2", "吃喝玩乐"));
tests.add(new Test("11", "2", "学习"));
tests.add(new Test("12", "3", "String"));
tests.add(new Test("13", "4", "sql"));
tests.add(new Test("14", "5", "ioc"));
tests.add(new Test("15", "5", "aop"));
tests.add(new Test("16", "1", "等等"));
tests.add(new Test("17", "2", "等等"));
tests.add(new Test("18", "3", "等等"));
tests.add(new Test("19", "4", "等等"));
tests.add(new Test("20", "5", "等等"));
Salin selepas log masuk

3、源码

Tree.java

package pers.kangxu.datautils.bean.tree;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import com.alibaba.fastjson.JSON;
/**
 * tree TODO <br>
 *
 * @author kangxu2 2017-1-7
 *
 */
public class Tree<T> {
  /**
   * 节点ID
   */
  private String id;
  /**
   * 显示节点文本
   */
  private String text;
  /**
   * 节点状态，open closed
   */
  private String state = "open";
  /**
   * 节点是否被选中 true false
   */
  private boolean checked = false;
  /**
   * 节点属性
   */
  private List<Map<String, Object>> attributes;
  /**
   * 节点的子节点
   */
  private List<Tree<T>> children = new ArrayList<Tree<T>>();
  /**
   * 父ID
   */
  private String parentId;
  /**
   * 是否有父节点
   */
  private boolean isParent = false;
  /**
   * 是否有子节点
   */
  private boolean isChildren = false;
  public String getId() {
    return id;
  }
  public void setId(String id) {
    this.id = id;
  }
  public String getText() {
    return text;
  }
  public void setText(String text) {
    this.text = text;
  }
  public String getState() {
    return state;
  }
  public void setState(String state) {
    this.state = state;
  }
  public boolean isChecked() {
    return checked;
  }
  public void setChecked(boolean checked) {
    this.checked = checked;
  }
  public List<Map<String, Object>> getAttributes() {
    return attributes;
  }
  public void setAttributes(List<Map<String, Object>> attributes) {
    this.attributes = attributes;
  }
  public List<Tree<T>> getChildren() {
    return children;
  }
  public void setChildren(List<Tree<T>> children) {
    this.children = children;
  }
  public boolean isParent() {
    return isParent;
  }
  public void setParent(boolean isParent) {
    this.isParent = isParent;
  }
  public boolean isChildren() {
    return isChildren;
  }
  public void setChildren(boolean isChildren) {
    this.isChildren = isChildren;
  }
  public String getParentId() {
    return parentId;
  }
  public void setParentId(String parentId) {
    this.parentId = parentId;
  }
  public Tree(String id, String text, String state, boolean checked,
      List<Map<String, Object>> attributes, List<Tree<T>> children,
      boolean isParent, boolean isChildren, String parentID) {
    super();
    this.id = id;
    this.text = text;
    this.state = state;
    this.checked = checked;
    this.attributes = attributes;
    this.children = children;
    this.isParent = isParent;
    this.isChildren = isChildren;
    this.parentId = parentID;
  }
  public Tree() {
    super();
  }
  @Override
  public String toString() {
    return JSON.toJSONString(this);
  }
}
Salin selepas log masuk

BuildTree.java

package pers.kangxu.datautils.common.tree;
import java.util.ArrayList;
import java.util.List;
import pers.kangxu.datautils.bean.tree.Tree;
/**
 * 构建tree
 * TODO
 * <br>
 * @author kangxu2 2017-1-7
 *
 */
public class BuildTree {
  /**
   *
   * TODO
   * <br>
   * @author kangxu2 2017-1-7
   *
   * @param nodes
   * @return
   */
  public static <T> Tree<T> build(List<Tree<T>> nodes) {
    if(nodes == null){
      return null;
    }
    List<Tree<T>> topNodes = new ArrayList<Tree<T>>();
    for (Tree<T> children : nodes) {
      String pid = children.getParentId();
      if (pid == null || "".equals(pid)) {
        topNodes.add(children);
        continue;
      }
      for (Tree<T> parent : nodes) {
        String id = parent.getId();
        if (id != null && id.equals(pid)) {
          parent.getChildren().add(children);
          children.setParent(true);
          parent.setChildren(true);
          continue;
        }
      }
    }
    Tree<T> root = new Tree<T>();
    if (topNodes.size() == 0) {
      root = topNodes.get(0);
    } else {
      root.setId("-1");
      root.setParentId("");
      root.setParent(false);
      root.setChildren(true);
      root.setChecked(true);
      root.setChildren(topNodes);
      root.setText("顶级节点");
    }
    return root;
  }
}
Salin selepas log masuk

BuildTreeTester.java

package pers.kangxu.datautils.test;
import java.util.ArrayList;
import java.util.List;
import pers.kangxu.datautils.bean.tree.Tree;
import pers.kangxu.datautils.common.tree.BuildTree;
public class BuildTreeTester {
  public static void main(String[] args) {
    List<Tree<Test>> trees = new ArrayList<Tree<Test>>();
    List<Test> tests = new ArrayList<Test>();
    tests.add(new Test("0", "", "关于本人"));
    tests.add(new Test("1", "0", "技术学习"));
    tests.add(new Test("2", "0", "兴趣"));
    tests.add(new Test("3", "1", "JAVA"));
    tests.add(new Test("4", "1", "oracle"));
    tests.add(new Test("5", "1", "spring"));
    tests.add(new Test("6", "1", "springmvc"));
    tests.add(new Test("7", "1", "fastdfs"));
    tests.add(new Test("8", "1", "linux"));
    tests.add(new Test("9", "2", "骑行"));
    tests.add(new Test("10", "2", "吃喝玩乐"));
    tests.add(new Test("11", "2", "学习"));
    tests.add(new Test("12", "3", "String"));
    tests.add(new Test("13", "4", "sql"));
    tests.add(new Test("14", "5", "ioc"));
    tests.add(new Test("15", "5", "aop"));
    tests.add(new Test("16", "1", "等等"));
    tests.add(new Test("17", "2", "等等"));
    tests.add(new Test("18", "3", "等等"));
    tests.add(new Test("19", "4", "等等"));
    tests.add(new Test("20", "5", "等等"));
    for (Test test : tests) {
      Tree<Test> tree = new Tree<Test>();
      tree.setId(test.getId());
      tree.setParentId(test.getPid());
      tree.setText(test.getText());
      trees.add(tree);
    }
    Tree<Test> t = BuildTree.build(trees);
    System.out.println(t);
  }
}
class Test {
  private String id;
  private String pid;
  private String text;
  public String getId() {
    return id;
  }
  public void setId(String id) {
    this.id = id;
  }
  public String getPid() {
    return pid;
  }
  public void setPid(String pid) {
    this.pid = pid;
  }
  public String getText() {
    return text;
  }
  public void setText(String text) {
    this.text = text;
  }
  public Test(String id, String pid, String text) {
    super();
    this.id = id;
    this.pid = pid;
    this.text = text;
  }
  public Test() {
    super();
  }
  @Override
  public String toString() {
    return "Test [id=" + id + ", pid=" + pid + ", text=" + text + "]";
  }
}
Salin selepas log masuk

4、运行结果

JSON数据：

{
  "checked": true,
  "children": [
    {
      "checked": false,
      "children": [
        {
          "checked": false,
          "children": [
            {
              "checked": false,
              "children": [
                {
                  "checked": false,
                  "children": [],
                  "id": "12",
                  "parent": true,
                  "parentId": "3",
                  "state": "open",
                  "text": "String"
                },
                {
                  "checked": false,
                  "children": [],
                  "id": "18",
                  "parent": true,
                  "parentId": "3",
                  "state": "open",
                  "text": "等等"
                }
              ],
              "id": "3",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "JAVA"
            },
            {
              "checked": false,
              "children": [
                {
                  "checked": false,
                  "children": [],
                  "id": "13",
                  "parent": true,
                  "parentId": "4",
                  "state": "open",
                  "text": "sql"
                },
                {
                  "checked": false,
                  "children": [],
                  "id": "19",
                  "parent": true,
                  "parentId": "4",
                  "state": "open",
                  "text": "等等"
                }
              ],
              "id": "4",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "oracle"
            },
            {
              "checked": false,
              "children": [
                {
                  "checked": false,
                  "children": [],
                  "id": "14",
                  "parent": true,
                  "parentId": "5",
                  "state": "open",
                  "text": "ioc"
                },
                {
                  "checked": false,
                  "children": [],
                  "id": "15",
                  "parent": true,
                  "parentId": "5",
                  "state": "open",
                  "text": "aop"
                },
                {
                  "checked": false,
                  "children": [],
                  "id": "20",
                  "parent": true,
                  "parentId": "5",
                  "state": "open",
                  "text": "等等"
                }
              ],
              "id": "5",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "spring"
            },
            {
              "checked": false,
              "children": [],
              "id": "6",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "springmvc"
            },
            {
              "checked": false,
              "children": [],
              "id": "7",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "fastdfs"
            },
            {
              "checked": false,
              "children": [],
              "id": "8",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "linux"
            },
            {
              "checked": false,
              "children": [],
              "id": "16",
              "parent": true,
              "parentId": "1",
              "state": "open",
              "text": "等等"
            }
          ],
          "id": "1",
          "parent": true,
          "parentId": "0",
          "state": "open",
          "text": "技术学习"
        },
        {
          "checked": false,
          "children": [
            {
              "checked": false,
              "children": [],
              "id": "9",
              "parent": true,
              "parentId": "2",
              "state": "open",
              "text": "骑行"
            },
            {
              "checked": false,
              "children": [],
              "id": "10",
              "parent": true,
              "parentId": "2",
              "state": "open",
              "text": "吃喝玩乐"
            },
            {
              "checked": false,
              "children": [],
              "id": "11",
              "parent": true,
              "parentId": "2",
              "state": "open",
              "text": "学习"
            },
            {
              "checked": false,
              "children": [],
              "id": "17",
              "parent": true,
              "parentId": "2",
              "state": "open",
              "text": "等等"
            }
          ],
          "id": "2",
          "parent": true,
          "parentId": "0",
          "state": "open",
          "text": "兴趣"
        }
      ],
      "id": "0",
      "parent": false,
      "parentId": "",
      "state": "open",
      "text": "关于本人"
    }
  ],
  "id": "-1",
  "parent": false,
  "parentId": "",
  "state": "open",
  "text": "顶级节点"
}
Salin selepas log masuk

更多JAVA 根据数据库表内容生产树结构JSON数据的实例代码相关文章请关注PHP中文网！

Label berkaitan：
java 数据库 树形 结构
sumber：php.cn
Artikel sebelumnya：Java递归算法经典实例（经典兔子问题） Artikel seterusnya：Java实现简单树结构
Kenyataan Laman Web ini
Kandungan artikel ini disumbangkan secara sukarela oleh netizen, dan hak cipta adalah milik pengarang asal. Laman web ini tidak memikul tanggungjawab undang-undang yang sepadan. Jika anda menemui sebarang kandungan yang disyaki plagiarisme atau pelanggaran, sila hubungi admin@php.cn
Artikel terbaru oleh pengarang
Isu terkini
**Jenis ralat: Tidak dapat mengulangi objek 'NoneType'** Saya mahu menggunakan terowong ssh untuk mengakses pangkalan data Mysql. Malangnya, seni b...
daripada 2024-04-06 10:26:38
0
1
378
Alih keluar nod daripada pangkalan data masa nyata Firebase berdasarkan nilai bersarang menggunakan kekunci rawak Saya mempunyai pangkalan data langsung dengan struktur berikut: "keys":"ran...
daripada 2024-04-03 18:10:45
0
2
332
Ralat "MODULE NOT FUND", modul tidak ditemui Saya cuba menyelesaikan masalah laluan: ini ialah struktur fail saya: /www/html//database/...
daripada 2024-04-02 17:27:55
0
1
449
Bagaimanakah cara saya mengkonfigurasi Vite untuk mengakses fail di luar folder awam? Saya mempunyai struktur fail ini: aplikasi projek saya bootstrap config pangkalan data nod...
daripada 2024-04-02 12:39:53
0
1
397
Akan memindahkan medan BLOB dalam jadual MySQL ke medan BLOB dalam jadual SQLite Saya mempunyai jadual dalam pangkalan data mysql yang mengandungi satu lajur jenis BLOB. S...
daripada 2024-04-01 11:14:54
0
1
432
Topik-topik yang berkaitan
Lagi>
Cadangan popular
Tutorial Popular
Lagi>
Tutorial berkaitan
Cadangan popular
Kursus terkini
Muat turun terkini
Lagi>
kesan web
Kod sumber laman web
Bahan laman web
Templat hujung hadapan