Java通用树构建方法
今天写了一个通用树构建方法,非常通用和简单,分享出来
基础类
@Data public class Tree<T> { String id; String pId; List<T> children; } 测试类 @Data public class TreeDemo extends Tree<TreeDemo> { String name; } 工具类 public class TreeUtils { public static List buildTree(List<Tree> trees, String pId) { for (Tree tree : trees) { for (Tree tree1 : trees) { if (tree1.getPId().equals(tree.getId())) { if (tree.getChildren() == null) { tree.setChildren(new ArrayList()); } tree.getChildren().add(tree1); } } } return trees.stream().filter(tree -> tree.getPId().equals(pId)).collect(Collectors.toList()); } }
测试方法
public static void main(String[] args) {
List<TreeDemo> treeDemo = TreeUtils.buildTree(Arrays.asList(new TreeDemo(){{
setId("1");
setName("name");
setPId("-1");
}},new TreeDemo(){{
setId("2");
setName("name-1");
setPId("1");
}},new TreeDemo(){{
setId("3");
setName("name-2");
setPId("1");
}}),"-1");
System.out.println(treeDemo);
}