使用spring-data-mongod把文件存入mongodb gridfs，
并实现增删查。
首先新建一个springboot项目
文件结构如下
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在application.properties配置mongodb的database
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核心代码
GridfsService代码
package com.awlsx.gridfsdemo;
import com.mongodb.BasicDBObject;
import com.mongodb.gridfs.GridFS;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;
import org.bson.types.ObjectId;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import java.io.InputStream;
import java.util.Date;
@Service
public class GridfsService {
@Autowired
private MongoDbFactory mongodbfactory;
/**
* 插入文件
* @param file
* @return
*/
public GridFSInputFile save(MultipartFile file){
GridFS gridFS = new GridFS(mongodbfactory.getDb());
try{
InputStream in = file.getInputStream();
String name = file.getOriginalFilename();
GridFSInputFile gridFSInputFile = gridFS.createFile(in);
gridFSInputFile.setFilename(name);
gridFSInputFile.setContentType(file.getContentType());
gridFSInputFile.save();
return gridFSInputFile;
}
catch (Exception e){}
return null;
}
/**
* 据id返回文件
*/
public GridFSDBFile getById(ObjectId id){
GridFS gridFS = new GridFS(mongodbfactory.getDb());
return gridFS.findOne(new BasicDBObject("_id", id));
}
/**
* 删除
* @param id
*/
public void remove(String id) {
GridFS gridFS = new GridFS(mongodbfactory.getDb());
gridFS.remove(new ObjectId(id));
}
}
Controller文件代码
package com.awlsx.gridfsdemo;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.mongodb.gridfs.GridFSDBFile;
import com.mongodb.gridfs.GridFSInputFile;
import org.bson.types.ObjectId;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletResponse;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;
@RestController
public class Controller {
@Autowired
private GridfsService gridfsService;
@RequestMapping(value = "/file/upload")
public Object uploadData(@RequestParam(value = "file")MultipartFile file) {
GridFSInputFile inputFile = gridfsService.save(file);
if (inputFile == null) {
return "upload fail";
}
String id = inputFile.getId().toString();
String md5 = inputFile.getMD5();
String name = inputFile.getFilename();
long length = inputFile.getLength();
Map<String,Object> dt = new HashMap<String,Object>();
dt.put("id",id);
dt.put("md5",md5);
dt.put("name",name);
dt.put("length",length);
return dt;
}
/**
* 删除
* @param id
* @return
*/
@RequestMapping(value = "/file/delete", method = RequestMethod.POST)
public Object deleteFile(@RequestParam(value = "id") String id) {
// 删除文件
gridfsService.remove(id);
return "delete ok";
}
/**
* 下载文件
* @param id
* @param response
*/
@RequestMapping(value = "/file/{id}", method = RequestMethod.GET)
public void getFile(@PathVariable String id, HttpServletResponse response) {
GridFSDBFile file = gridfsService.getById(new ObjectId(id));
if (file == null) {
responseFail("404 not found",response);
return;
}
OutputStream os = null;
try {
os = response.getOutputStream();
response.addHeader("Content-Disposition", "attachment;filename=" + file.getFilename());
response.addHeader("Content-Length", "" + file.getLength());
response.setContentType("application/octet-stream");
file.writeTo(os);
os.flush();
os.close();
} catch (Exception e) {
try{
if (os != null) {
os.close();
}
}catch (Exception e2){}
e.printStackTrace();
}
}
@RequestMapping(value = "/file/view/{id}", method = RequestMethod.GET)
public void viewFile(@PathVariable String id, HttpServletResponse response) {
GridFSDBFile file = gridfsService.getById(new ObjectId(id));
if (file == null) {
responseFail("404 not found",response);
return;
}
OutputStream os = null;
try {
os = response.getOutputStream();
response.addHeader("Content-Disposition", "attachment;filename=" + file.getFilename());
response.addHeader("Content-Length", "" + file.getLength());
response.setContentType(file.getContentType());
file.writeTo(os);
os.flush();
os.close();
} catch (Exception e) {
try{
if (os != null) {
os.close();
}
}catch (Exception e2){}
e.printStackTrace();
}
}
private void responseFail(String msg,HttpServletResponse response) {
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json; charset=utf-8");
PrintWriter out = null;
ObjectMapper mapper = new ObjectMapper();
try{
String res = mapper.writeValueAsString(msg);
out = response.getWriter();
out.append(res);
} catch (Exception e){
try {
if (out != null) {
out.close();
}
}catch (Exception e2) {}
}
}
}
运行程序
先上传文件
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预览文件
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下载文件
把链接贴到浏览器地址栏，发现文件已经下载下来了。
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删除文件，成功
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查看数据库，发现数据库中多了两个collection
db.png
查看数据库中fs.files，文件已经成功被删除
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