mongodb文件上传下载删除查询
在mongo-java-driver3.x以上的版本中逐渐弃用了Mongo和getDB等一系列方法，所以原来的GridFS的用法也发生了一些改变
改进前：
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.MongoClient;
import com.mongodb.gridfs.GridFS;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;
public class GridTest {
private static final Logger log = LoggerFactory.getLogger(GridTest.class);
public static void main(String[] args) throws FileNotFoundException{
// 连接到 mongodb 服务
@SuppressWarnings("resource")
MongoClient mongoClient = new MongoClient( "localhost" , 27017 );
@SuppressWarnings("deprecation")
DB db = mongoClient.getDB("test");
log.info("成功连接数据库");
String collectionName="mongoCollectionTest";
GridFS gridFS = new GridFS(db,collectionName);
/*
* 2、上传文件
*/
//创建测试文件，mongo 默认存在该文件
File file=new File("E:-----------.pdf");
FileInputStream fileInputStream=new FileInputStream(file);
//创建gridFS文件数据流
GridFSInputFile createFile=gridFS.createFile(fileInputStream);
//设置文件属性
createFile.put("filename", "123.pdf");
createFile.put("contentType", "application/pdf");
createFile.save();
/*
* 3、根据id查询上传文件
*/
GridFSDBFile findOne= gridFS.findOne(new BasicDBObject("_id",createFile.getId()));
System.out.print(findOne);
}
}
改进后：
import com.mongodb.MongoClient;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.gridfs.GridFSBucket;
import com.mongodb.client.gridfs.GridFSBuckets;
import com.mongodb.client.gridfs.model.GridFSUploadOptions;
import org.bson.Document;
import org.bson.types.ObjectId;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.*;
import java.util.UUID;
public class MongoDBTest {
private static Logger log = LoggerFactory.getLogger(MongoDbUtil.class);
private static final class MongoInstance {
public final static MongoClient client;
static {
client = new MongoClient("localhost", 27017);
}
}public static MongoDatabase getDatabase(String databaseName) {
return MongoInstance.client.getDatabase(databaseName);
}/**
* 上传文件
* @param file
* @param databaseName
* @return
*/
public static String uploadFileToGridFS(File file,String databaseName) {
InputStream in = null;
String returnId = null;
String pathName = file.getPath();
String[] pathNameArray = pathName.split("\\\\");
String[] name = pathNameArray[pathNameArray.length-1].split("\\.");
String filename = name[0];
String type = name[name.length-1];
try {
in = new FileInputStream(file);
GridFSBucket bucket = GridFSBuckets.create(getDatabase(databaseName));
GridFSUploadOptions options = new GridFSUploadOptions();
//设置除filename以为的其他信息
Document metadata = https://www.it610.com/article/new Document();
metadata.append("contentType", type);
options.metadata(metadata);
ObjectId fileId = bucket.uploadFromStream(filename+type, in,options);
returnId = fileId.toHexString();
log.info("文件上传成功");
} catch (IOException e) {
log.info("upload fail:" + e);
} finally {
try {
in.close();
} catch (IOException e) {
log.info("close inputstream fail:" + e);
}
}
return returnId;
}/**
* 通过objectid和file下载文件
* @param objectId
* @param file
* @param databaseName
*/
public static void downloadFile(String objectId, File file,String databaseName) {
OutputStream os = null;
try {
os = new FileOutputStream(file);
GridFSBucket bucket = GridFSBuckets.create(getDatabase(databaseName));
bucket.downloadToStream(new ObjectId(objectId), os);
log.info("文件下载成功");
} catch (IOException e) {
log.info("download fail:" + e);
} finally {
if (os != null) {
try {
os.close();
} catch (IOException e) {
log.info("close outputstream fail:" + e);
}
}
}
}/**
* 通过objectid删除文件
* @param objectId
* @param databaseName
*/
public static void deleteByObjectId(String objectId,String databaseName) {
GridFSBucket bucket = GridFSBuckets.create(getDatabase(databaseName));
bucket.delete(new ObjectId(objectId));
log.info("文件删除成功");
}/**
* 查询文件
* @param databaseName
*/
public static List find(String databaseName){
GridFSBucket bucket = GridFSBuckets.create(getDatabase(databaseName));
GridFSFindIterable iterable = bucket.find();
MongoCursor mongoCursor= iterable.iterator();
List results = new ArrayList();
while(mongoCursor.hasNext()){
results.add(mongoCursor.next());
}
return results;
}/**
* 查询文件
* @param databaseName
*/
public static List findBy(String databaseName,Bson filter){
GridFSBucket bucket = GridFSBuckets.create(getDatabase(databaseName));
GridFSFindIterable iterable = bucket.find(filter);
MongoCursor mongoCursor= iterable.iterator();
List results = new ArrayList();
while(mongoCursor.hasNext()){
results.add(mongoCursor.next());
}
return results;
}
}
import java.io.File;
import org.junit.Test;
public class MongoGridFSTest
{
/**
* 先上传
*/
@Test
public void upload() {
File file = new File("C:/Users/Administrator/Desktop/Java持久化之myBatis3.pdf");
String databaseName = "test";
String objectId = MongoDbFSUtil.uploadFileToGridFS(file,databaseName);
System.out.println(objectId);
System.out.println("文件上传成功");
}/**
* 测试下载
*/
@Test
public void download() {
//System.out.println(objectId);
File file = new File("D:/1.pdf");
String databaseName = "test";
MongoDbFSUtil.downloadFile("594b8298932ed623249dea18", file,databaseName);
System.out.println("文件下载成功");
}/**
* 最后将上传的信息删除
*/
@Test
public void delete() {
String databaseName = "test";
MongoDbFSUtil.deleteByObjectId("594b3b53932ed60b043ac4c8",databaseName);
}
@Test
public void find(){
List results= MongoDbFSUtil.find("test");
for(GridFSFile file: results){
System.out.println(file.toString());
}
}@Test
public void findBy(){
Document filter = new Document();
filter.append("filename", "深入理解Java虚拟机：JVM高级特性与最佳实践.pdf");
List results= MongoDbFSUtil.findBy("test",filter);
for(GridFSFile file: results){
System.out.println(file.getId());
}
}
【mongodb文件上传下载删除查询】}
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