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"));
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() == 1) {
root = topNodes.get(0);
} else {
root.setId("-1");
root.setParentId("");
root.setParent(false);
root.setChildren(true);
root.setChecked(true);
root.setChildren(topNodes);
root.setText("*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":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"
}