#yyds干货盘点#java获取文件树

1.文件树结构

@ApiModel("文件树")
@JsonInclude(value = JsonInclude.Include.NON_NULL)
@Data
public class BaseTreeNodeVO {
    @ApiModelProperty(value = "文件id", required = true)
    protected Long id;

    @ApiModelProperty(value = "父id", required = true)
    protected Long parentId;

    @ApiModelProperty(value = "文件夹标识", required = true)
    protected Boolean isDirectory;

    @ApiModelProperty(value = "文件名", required = true)
    private String name;

    @ApiModelProperty(value = "子节点", required = true)
    protected List<BaseTreeNodeVO> children = new ArrayList<>();

    public void  appendChild(BaseTreeNodeVO organTree){
        this.children.add(organTree);
    }
}

2.获取文件树

public BaseTreeNodeVO getFileTree(String filePath){

        long parentId = 1;  //初始化父节点id
        long id = 1;  //初始化父节点id
        List<FileTree> list = new ArrayList<>();
        try {
            FileUtil.file(id,filePath,parentId,list);

        } catch (FileNotFoundException                                                                                                                                       e) {
            e.printStackTrace();
        }

        BaseTreeNodeVO bt = FileUtil.assembleTree(list);
        bt = FileUtil.sort(bt);
        LOG.info(LogProperty.LOGTYPE_DETAIL, JSON.toJSONString(bt));
        return bt;
    }

3.转换为list

public static List<FileTree> file(Long id,String filePath,long parentId, List<FileTree> treeList) throws FileNotFoundException {
        File file = new File(filePath);

        //1.判断文件
        if(!file.exists()){
            throw new FileNotFoundException("文件不存在");
        }

        //3.获取文件夹路径下面的所有文件递归调用；
        if(file.isDirectory()){
            String path = file.getAbsolutePath();
            String name = file.getName();
            FileTree fileTree = new FileTree(id++,name,path,parentId,true);
            treeList.add(fileTree);
            String[] list = file.list();
            for (int i = 0;i<list.length;i++){
                String s = list[i];
                String newFilePath = path+ File.separator +s;//根据当前文件夹，拼接其下文文件形成新的路径
                file(id++,newFilePath,fileTree.getId(),treeList);
            }
        }
        //2.是文件该怎么执行
        if(file.isFile()){
            LOG.info(LogProperty.LOGTYPE_DETAIL, "is file");
            String name = file.getName();
            String path = file.getAbsolutePath();
            FileTree fileTree = new FileTree(id++,name,path,parentId,false);
            treeList.add(fileTree);
            return treeList;
        }

        return  treeList;
    }

4.转换为tree

public static <T extends BaseTreeNodeVO> T assembleTree(List<T> list) {

        if (list.isEmpty()) {
            return null;
        }

        //取出根节点
        T root = list.get(0);
        //临时存放所有节点
        Map<Long, T> nodeMap = new HashMap<>();
        list.stream().forEach(o -> nodeMap.put(o.getId(), o));
        //找出节点关系
        list.subList(1, list.size()).stream().forEach(m -> nodeMap.get(m.getParentId()).appendChild(m));
        list.stream().sorted(Comparator.comparing(BaseTreeNodeVO::getIsDirectory)).collect(Collectors.toList());
        nodeMap.clear();
        return root;
    }

5.排序

public static BaseTreeNodeVO sort(BaseTreeNodeVO bt) {

        List<BaseTreeNodeVO> list = bt.getChildren();
        while (!list.isEmpty()) {
            List<BaseTreeNodeVO> dir = list.stream().filter(a -> a.getIsDirectory()).collect(Collectors.toList());
            Collections.sort(dir, Comparator.comparing(BaseTreeNodeVO::getName));
            List<BaseTreeNodeVO> file = list.stream().filter(a -> !a.getIsDirectory()).collect(Collectors.toList());
            Collections.sort(file, Comparator.comparing(BaseTreeNodeVO::getName));
            for (BaseTreeNodeVO btChildren : dir) {
                sort(btChildren);
            }
            dir.addAll(file);
            bt.setChildren(dir);
            return bt;
        }
        return bt;
    }
}

6.接口返回示例