Java8 之List＜List＜Map＞＞合并為List＜Map＞

怼烎@ 2023-10-10 13:43 40阅读 0赞

废话不多说，直接上源码：

Map<String, Object> parame = new HashMap<String, Object>();
    		List<Map> originals = null;
    		if(BusinessConstant.ARCH.equalsIgnoreCase(type)){
    			parame.put("archSid", sid);
    			List<UcasFileInfo> list = ucasFileInfoService.selectAll(parame);
    			if(CollectionUtils.isNotEmpty(list)){
    				 List<List<Map>> colls = list.stream().filter(item->{
    					return StringUtils.isNotEmpty(item.getPdfSourcePath());
    				}).map(item->{
    					return this.getPdfSourcePath(item.getPdfSourcePath(), item.getSid(), item.getFileTitle());
    				}).collect(Collectors.toList());
    				 originals = colls.stream().collect(ArrayList::new, ArrayList::addAll, ArrayList::addAll);
    			}
    		}

/**
    	 * 获取指定文件的所有原文文件信息
    	 * @param key
    	 * @return
    	 */
    	public List<Map> getPdfSourcePath(String pdfSourcePath, String sid, String fileName){
    		List<Map> container = new ArrayList<Map>();
    		// 存储标识符
    		String key = FilePathConvertUtil.mathPathKeyByFilePath(pdfSourcePath);
    		String fileDirectory = sysEfileStoreService.findPathByKey(key);
    		String fileDirectoryPath = StringUtils.replaceFirst(pdfSourcePath, key, fileDirectory);
    		
    		List<File> list =  Arrays.asList(new File(fileDirectoryPath).listFiles());
    		//List<File> list = (List<File>) FileUtils.listFiles(new File(fileDirectoryPath), new String[]{}, false);
    		if(CollectionUtils.isNotEmpty(list)){
    			list.stream().forEach(item->{
    				Map<String, String> map = new HashMap<String, String>();
    				map.put("fileName", item.getName());
    				// 文件路径自己拼接
    				map.put("filePath", fileDirectoryPath.concat(File.separator).concat(item.getName()));
    				map.put("fileType", FilenameUtils.getExtension(item.getName()));
    				map.put("fileTitle", fileName);
    				map.put("fileSid", sid);
    				map.put("fileDirectory", fileDirectory);
    				container.add(map);
    			});
    		}
    		
    		return container;
    	}

核心功能代码:

> originals = colls.stream().collect(ArrayList::new, ArrayList::addAll, ArrayList::addAll);