@Autowiredprivate TreeBuilder treeBuilder; /*** 獲取樹狀結構數據*/@RequestMapping("menu/queryMenuTree")@ResponseBodypublic Object queryMenuTree(int id){//查詢Node數據List<Node> list=menuService.queryMenuTree();//根據角色查詢關聯到的菜單List<RoleMenu> roleMenus=menuService.queryMenuByRoleId(id);//渲染已經選中內容for(RoleMenu rm:roleMenus){//獲取當前對象的idint menuId=rm.getMenuId();for(Node node:list){if(node.getId()==menuId){node.setChecked(true);}}}//組裝樹結構String result =treeBuilder.buildTree(list);return result;} @Component("treeBuilder") public class TreeBuilder {List<Node> nodes = new ArrayList<>();public String buildTree(List<Node> nodes) {TreeBuilder treeBuilder = new TreeBuilder(nodes);return treeBuilder.buildJSONTree();}public TreeBuilder() {}public TreeBuilder(List<Node> nodes) {super();this.nodes = nodes;}// 構建JSON樹形結構public String buildJSONTree() {List<Node> nodeTree = buildTree();String jsonStr = JSON.toJSONString(nodeTree);return jsonStr;}// 構建樹形結構public List<Node> buildTree() {List<Node> treeNodes = new ArrayList<>();List<Node> rootNodes = getRootNodes();for (Node rootNode : rootNodes) {buildChildNodes(rootNode);treeNodes.add(rootNode);}return treeNodes;}// 遞歸子節點public void buildChildNodes(Node node) {List<Node> children = getChildNodes(node);if (!children.isEmpty()) {for (Node child : children) {buildChildNodes(child);}node.setChildren(children);}}// 獲取父節點下所有的子節點public List<Node> getChildNodes(Node pnode) {List<Node> childNodes = new ArrayList<>();for (Node n : nodes) {if (pnode.getId().equals(n.getParentId())) {childNodes.add(n);}}return childNodes;}// 判斷是否為根節點public boolean rootNode(Node node) {boolean isRootNode = true;for (Node n : nodes) {if (node.getParentId().equals(n.getId())) {isRootNode = false;break;}}return isRootNode;}// 獲取集合中所有的根節點public List<Node> getRootNodes() {List<Node> rootNodes = new ArrayList<>();for (Node n : nodes) {System.out.println(n);if (rootNode(n)) {rootNodes.add(n);}}return rootNodes;}} @Data public class Node {private Integer id;private Integer parentId;private String title;private List<Node> children;private Boolean checked;//是否選中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 getTitle() {return title;}public void setTitle(String title) {this.title = title;}public List<Node> getChildren() {return children;}public void setChildren(List<Node> children) {this.children = children;}public Boolean getChecked() {return checked;}public void setChecked(Boolean checked) {this.checked = checked;} }

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