与GridJs服务器端配合工作

与GridJs服务器端配合工作

0. 在配置中设置正确的文件夹路径

Config.setFileCacheDirectory 用于工作簿缓存文件（必需）。 Config.setPictureCacheDirectory 用于工作簿中的图像文件缓存（可选，默认值为文件缓存目录中的 _piccache）。

有关存储详细信息，请查看此 指南

1. 实现 GridCacheForStream

对于本地文件存储，这里有一个示例：

public class LocalFileCache extends GridCacheForStream {

	@Override
	public void saveStream(InputStream s, String uid) {
		// make sure the directory is exist
		String filepath = Paths.get(Config.getFileCacheDirectory(), "streamcache", uid.replace('/', '.')).toString();
		try (FileOutputStream fos = new FileOutputStream(filepath.toString())) {
			s.reset(); // Equivalent to s.Position = 0 in C#
			byte[] buffer = new byte[1024];
			int length;
			while ((length = s.read(buffer)) > 0) {
				fos.write(buffer, 0, length);
			}
			fos.flush();
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

	@Override
	public InputStream loadStream(String uid) {
		String filepath = Paths.get(Config.getFileCacheDirectory(), "streamcache", uid.replace('/', '.')).toString();
		try {
			return new FileInputStream(filepath);
		} catch (FileNotFoundException e) {
			e.printStackTrace();
			return null;
		}
	}

	@Override
	public boolean isExisted(String uid) {
		String filepath = Paths.get(Config.getFileCacheDirectory(), "streamcache", uid.replace('/', '.')).toString();
		return Files.exists(Paths.get(filepath));
	}

	@Override
	public String getFileUrl(String uid) {
		return "/GridJs2/GetFileUseCacheStream?id=" + uid;
	}

}

2. 从电子表格文件向响应流写入 json。

            GridJsWorkbook wbj = new GridJsWorkbook();
            try (GZIPOutputStream gzipOutputStream = new GZIPOutputStream(response.getOutputStream())) {
                wbj.importExcelFile(filePath.toString());
                wbj.jsonToStream(gzipOutputStream, filename);
            } catch (IOException e) {
				e.printStackTrace();
            } catch (Exception e) {
				e.printStackTrace();
            }

3. 从电子表格文件中获取图像/形状

//Gridjs will automatically zip all the images/shapes into a zip stream  and store it in cache using the cache implemention.

InputStream inputStream = GridJsWorkbook.CacheImp.loadStream(fileid);

4. 在缓存中更新电子表格文件

GridJsWorkbook gwb = new GridJsWorkbook();
//p is the update json,uid is the unique id for the spreadsheet
String ret = gwb.updateCell(p, uid);

5. 将电子表格文件保存在缓存中

GridJsWorkbook wb = new GridJsWorkbook();
//p is the update json,uid is the unique id for the spreadsheet
wb.mergeExcelFileFromJson(uid, p);
wb.saveToCacheWithFileName(uid, filename,password);

有关详细信息，请查看此处的示例： https://github.com/aspose-cells/Aspose.Cells-for-java/tree/master/Examples_GridJs