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）
我要评论
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"));
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);
}
}
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;
}
}
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 + "]";
}
}
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"
}
以上就是小编为大家带来的java根据数据库表内容生产树结构json数据的方法全部内容了，希望大家多多支持移动技术网~
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