java机构

java后端递归树，机构树，遍历树

publicstaticvoidgetChildrenList(Listlist,JSONObjectpJo){

ListretList=newArrayList();

for(JSONObjectjo:list){

if(ing("pid").equals(ing("id"))){

(jo);

("children",getChildrenList(list,jo));

}

}

//returnretList;

("children",retList);

}

第⼀种，⽅法循环⼀次，⽐较耗费内存，不建议使⽤

publicstaticvoidmain(String[]args){

//拼装数据

Listlist=newArrayList();

(bject("{id:'1',name:'n1',pid:'-1'}"));

(bject("{id:'2',name:'n1',pid:'-1'}"));

(bject("{id:'3',name:'n1',pid:'-1'}"));

(bject("{id:'1-1',name:'n1-1',pid:'1'}"));

(bject("{id:'2-1',name:'n2-1',pid:'2'}"));

(bject("{id:'3-1',name:'n3-1',pid:'3'}"));

(bject("{id:'1-2',name:'n1-2',pid:'1'}"));

(bject("{id:'2-2',name:'n2-2',pid:'2'}"));

(bject("{id:'3-2',name:'n3-2',pid:'3'}"));

(bject("{id:'1-3',name:'n1-3',pid:'1'}"));

(bject("{id:'2-3',name:'n2-3',pid:'2'}"));

(bject("{id:'3-3',name:'n3-3',pid:'3'}"));

(bject("{id:'1-1-1',name:'n1-1-1',pid:'1-1'}"));

(bject("{id:'1-1-2',name:'n1-1-2',pid:'1-1'}"));

(bject("{id:'1-1-3',name:'n1-1-3',pid:'1-1'}"));

//递归根节点

JSONObjecttJo=bject("{id:'-1',name:'根节点'}");

//("children",getChildrenList(list,tJo));

n(String());

//⼀次循环⽅法，⽐较好内存不建议使⽤

Map>map1=newHashMap>();

for(JSONObjectjo:list){

Stringpid=ing("pid");

Stringid=ing("id");

if(!nsKey(pid)){//不存在

(pid,newArrayList());

}

(pid).add(jo);

if(!nsKey(id)){

(id,newArrayList());

}

("children",(id));

}

JSONObjecttJo2=bject("{id:'-1',name:'根节点'}");

("children",("-1"));

n(String());

}

第⼆种⽅法，两次循环，建议使⽤，节省内存

publicstaticvoidmain(String[]args){

//拼装数据

Listlist=newArrayList();

(bject("{id:'1',name:'n1',pid:'-1'}"));

(bject("{id:'2',name:'n1',pid:'-1'}"));

(bject("{id:'3',name:'n1',pid:'-1'}"));

(bject("{id:'1-1',name:'n1-1',pid:'1'}"));

(bject("{id:'2-1',name:'n2-1',pid:'2'}"));

(bject("{id:'3-1',name:'n3-1',pid:'3'}"));

(bject("{id:'1-2',name:'n1-2',pid:'1'}"));

(bject("{id:'2-2',name:'n2-2',pid:'2'}"));

(bject("{id:'3-2',name:'n3-2',pid:'3'}"));

(bject("{id:'1-3',name:'n1-3',pid:'1'}"));

(bject("{id:'2-3',name:'n2-3',pid:'2'}"));

(bject("{id:'3-3',name:'n3-3',pid:'3'}"));

(bject("{id:'1-1-1',name:'n1-1-1',pid:'1-1'}"));

(bject("{id:'1-1-2',name:'n1-1-2',pid:'1-1'}"));

(bject("{id:'1-1-3',name:'n1-1-3',pid:'1-1'}"));

//递归

JSONObjecttJo=bject("{id:'-1',name:'根节点'}");

//("children",getChildrenList(list,tJo));

n(String());

//两次循环⽅法，建议使⽤

Map>map=newHashMap>();

for(JSONObjectjo:list){

Stringpid=ing("pid");

if(!nsKey(pid)){//不存在

(pid,newArrayList());

}

(pid).add(jo);

}

for(JSONObjectjo:list){

Stringid=ing("id");

if(nsKey(id)){

("children",(id));

}

}

JSONObjecttJo1=bject("{id:'-1',name:'根节点'}");

("children",("-1"));

n(String());

}