Return file in Spring MVC REST

2019-03-27 06:59发布

问题:

I have the REST Service Code Below code which returns a File ,now the problem is in the response body on the PostMan Client I get a raw response ,how can I can convert it so that it displays the contents of the file to the client ,Goal is to return a file to the user .File Name is "File1.jpeg"

Code:

@RequestMapping(value = URIConstansts.GET_FILE, produces = { "application/json" }, method = RequestMethod.GET)
public @ResponseBody ResponseEntity getFile(@RequestParam(value="fileName", required=false) String fileName,HttpServletRequest request) throws IOException{

    ResponseEntity respEntity = null;

    byte[] reportBytes = null;
    File result=new File("/home/arpit/Documents/PCAP/dummyPath/"+fileName);

    if(result.exists()){
        InputStream inputStream = new FileInputStream("/home/arpit/Documents/PCAP/dummyPath/"+fileName); 


        byte[]out=org.apache.commons.io.IOUtils.toByteArray(inputStream);

        HttpHeaders responseHeaders = new HttpHeaders();
        responseHeaders.add("content-disposition", "attachment; filename=" + fileName);

        respEntity = new ResponseEntity(out, responseHeaders,HttpStatus.OK);


    }else{

        respEntity = new ResponseEntity ("File Not Found", HttpStatus.OK);
    }


    return respEntity;

}

回答1:

The code below solved my problem:

@RequestMapping(value = URIConstansts.GET_FILE, produces = { "application/json" }, method = RequestMethod.GET)
public @ResponseBody ResponseEntity getFile(@RequestParam(value="fileName", required=false) String fileName,HttpServletRequest request) throws IOException{

    ResponseEntity respEntity = null;

    byte[] reportBytes = null;
    File result=new File("/home/arpit/Documents/PCAP/dummyPath/"+fileName);

    if(result.exists()){
        InputStream inputStream = new FileInputStream("/home/arpit/Documents/PCAP/dummyPath/"+fileName);
        String type=result.toURL().openConnection().guessContentTypeFromName(fileName);

        byte[]out=org.apache.commons.io.IOUtils.toByteArray(inputStream);

        HttpHeaders responseHeaders = new HttpHeaders();
        responseHeaders.add("content-disposition", "attachment; filename=" + fileName);
        responseHeaders.add("Content-Type",type);

        respEntity = new ResponseEntity(out, responseHeaders,HttpStatus.OK);
    }else{
        respEntity = new ResponseEntity ("File Not Found", HttpStatus.OK);
    }
    return respEntity;
}


回答2:

You need to use different content type instead of produces = { application/json" }

Content-types

http://silk.nih.gov/public/zzyzzap.@www.silk.types.html

If it still dont work then try to get HttpServletResponse and write your file data to Stream with response.setContentType();

Note :: Recently I have use response.getOutputStream to write a Excel file. Due to some reasons setting produces wasnt working for me.

Also you can use Firebug in firefox to see Response headers.