mongodb的使用和分桶 mongodb

1、建立连接mongodb

private MongoClient mongoClient;

/**通过传来的用户名称和密码为空来判断是否需要进行认证连接 * @param ip * @param port * @param database * @return */ public MongoClient mongoConnection(String ip, int port, String database, String userName, String password) { try { if (StringUtil.isNotEmpty(ip) && StringUtil.isNotEmpty(database)) { MongoClient mongoClient = null; if (StringUtil.isNotEmpty(userName) && StringUtil.isNotEmpty(password)) {//开启验证 List adds = new ArrayList<>(); ServerAddress serverAddress = new ServerAddress(ip, port); adds.add(serverAddress); List credentials = new ArrayList<>(); MongoCredential mongoCredential = MongoCredential.createScramSha1Credential(userName, database, password.toCharArray()); credentials.add(mongoCredential); mongoClient = new MongoClient(adds, credentials); } else {//不开启验证 mongoClient = new MongoClient(ip, port); } return mongoClient; } else { return null; } } catch (Exception e) { return null; }}

【mongodb的使用和分桶】2、分桶上传文件到mongodb

try { GridFSBucket bucket = null; MongoDatabase db = mongoClient.getDatabase(数据库名称); //这里是根据年度分桶的 if(fiscal != null){ String name = "test_" + fiscal; //创建对应的文件桶 bucket = GridFSBuckets.create(db,name); }else{ bucket = GridFSBuckets.create(db); } ByteArrayInputStream input = new ByteArrayInputStream(bytes); ObjectId fileId = bucket.uploadFromStream(附件名称, input); //上传成功返回的标识fileId return fileId.toString(); } catch (Exception e) { throw new RuntimeException(e); }

不分桶上传mongodb文件

try { MongoDatabase db = mongoClient.getDatabase(数据库名称); GridFSBucket bucket = GridFSBuckets.create(db); ByteArrayInputStream inputStream = new ByteArrayInputStream(bytes); Object filed = bucket.uploadFromStream(附件名称, inputStream); //返回的标识位objectId（fileId） return filed.toString(); } catch (Exception e) { throw new RuntimeException(e); }

3、分桶读取mongodb上的文件（GridFSDownloadStream本身返回的是InputStream流）

GridFSDownloadStream gfStream = null; try { MongoDatabase db = mongoClient.getDatabase(数据库名称); //根据年度分桶，如果年度为空去默认的桶里读取文件 if(fiscal != null){ String name = "test_" + fiscal; GridFSBucket bucket = GridFSBuckets.create(db,name); GridFSFindIterable fsFiles = bucket.find(Filters.eq("_id",new ObjectId(fileId))); if(fsFiles.iterator().hasNext()){ //传来的标识位objectId（fileId） gfStream = bucket.openDownloadStream(new ObjectId(fileId)); }else { GridFSBucket buckets = GridFSBuckets.create(db); gfStream = buckets.openDownloadStream(new ObjectId(fileId)); } }else { GridFSBucket bucket1 = GridFSBuckets.create(db); gfStream = bucket1.openDownloadStream(new ObjectId(fileId)); } ByteArrayOutputStream out = new ByteArrayOutputStream(); //转换流 downloadToStream(gfStream, out); //返回byte数组 return out.toByteArray(); } catch (Exception ex) { return new byte[0]; } finally { if (gfStream != null) { try { gfStream.close(); } catch (Exception e) { } } } //转换流 private void downloadToStream(final GridFSDownloadStream downloadStream, final OutputStream destination) { byte[] buffer = new byte[downloadStream.getGridFSFile().getChunkSize()]; int len; MongoGridFSException savedThrowable = null; try { while ((len = downloadStream.read(buffer)) != -1) { destination.write(buffer, 0, len); } } catch (IOException e) { savedThrowable = new MongoGridFSException("IOException when reading from the OutputStream", e); } catch (Exception e) { savedThrowable = new MongoGridFSException( "Unexpected Exception when reading GridFS and writing to the Stream", e); } finally { if (savedThrowable != null) { throw savedThrowable; } } }

不分桶读取文件

GridFSDownloadStream gfStream = null; try { MongoDatabase db=mongoClient.getDatabase(数据库名称); GridFSBucket bucket = GridFSBuckets.create(db); //传来的标识位objectId gfStream = bucket.openDownloadStream(new ObjectId(objectId)); ByteArrayOutputStream out = new ByteArrayOutputStream(); downloadToStream(gfStream, out); if (out.size() == 0) { return null; } return out.toByteArray(); } catch (Exception ex) { return null; } finally { if (gfStream != null) { try { gfStream.close(); } catch (Exception e) { LOG.error("关闭FS下载流报错:", e); } } }

4、分桶删除文件

try { MongoDatabase db = mongoClient.getDatabase(数据库名称); if(fiscal != null){ String name = "test_" + fiscal; GridFSBucket bucket = GridFSBuckets.create(db,name); GridFSFindIterable fsFiles = bucket.find(Filters.eq("_id",new ObjectId(fileId))); //传来的标识位objectId（fileId） if(fsFiles.iterator().hasNext()){ bucket.delete(new ObjectId(fileId)); }else { GridFSBucket buckets = GridFSBuckets.create(db); buckets.delete(new ObjectId(fileId)); } }else { GridFSBucket bucket1 = GridFSBuckets.create(db); bucket1.delete(new ObjectId(fileId)); } } catch (Exception ex) { log.error("delete file error:", ex); }

不分桶删除文件

try { MongoDatabase db = mongoClient.getDatabase(数据库名称); GridFSBucket bucket = GridFSBuckets.create(db); //根据传来的标识位objectId bucket.delete(new ObjectId(objectId)); } catch (Exception e) { e.printStackTrace() return objectId; }