22

I want to send a file to webservice, but i need send more informations, so i want to send them with a json. But when i put a file inside my jsonObject i get an error saying that it isn't a string. My question is, should i take my File and convert to a string, then put inside my json and on web service take it and convert that string to a file? Or is there another simple way?

Here is my code:

Client:

private void send() throws JSONException{
    ClientConfig config = new DefaultClientConfig();
    Client client = Client.create(config);
    client.addFilter(new LoggingFilter());
    WebResource service = client.resource("http://localhost:8080/proj/rest/file/upload_json");

    JSONObject my_data = new JSONObject();
    File file_upload = new File("C:/hi.txt");
    my_data.put("User", "Beth");
    my_data.put("Date", "22-07-2013");
    my_data.put("File", file_upload);

    ClientResponse client_response = service.accept(MediaType.APPLICATION_JSON).post(ClientResponse.class, my_data);

    System.out.println("Status: "+client_response.getStatus());

    client.destroy();
}

WebService

@POST
@Path("/upload_json")

@Consumes(MediaType.APPLICATION_JSON)
@Produces("text/plain")

public String receive(JSONObject json) throws JSONException {

    //Here I'll save my file and make antoher things..
    return "ok";
}

After all the answers, here is my code - thanks everyone:

WebService

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import org.codehaus.jettison.json.JSONException;
import org.codehaus.jettison.json.JSONObject;
import com.sun.jersey.core.util.Base64;

@Path("/file")
public class ReceiveJSONWebService {

    @POST
    @Path("/upload_json")

    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)

    public JSONObject receiveJSON(JSONObject json) throws JSONException, IOException {
        convertFile(json.getString("file"), json.getString("file_name"));
        //Prints my json object
        return json;
    }

    //Convert a Base64 string and create a file
    private void convertFile(String file_string, String file_name) throws IOException{
        byte[] bytes = Base64.decode(file_string);
        File file = new File("local_path/"+file_name);
        FileOutputStream fop = new FileOutputStream(file);
        fop.write(bytes);
        fop.flush();
        fop.close();
    }
}

Client

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import javax.ws.rs.core.MediaType;
import org.codehaus.jettison.json.JSONException;
import org.codehaus.jettison.json.JSONObject;
import com.sun.jersey.api.client.Client;
import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.WebResource;
import com.sun.jersey.api.client.config.ClientConfig;
import com.sun.jersey.api.client.config.DefaultClientConfig;
import com.sun.jersey.api.client.filter.LoggingFilter;
import com.sun.jersey.core.util.Base64;
import com.sun.jersey.multipart.FormDataMultiPart;
import com.sun.jersey.multipart.file.FileDataBodyPart;
import com.sun.jersey.multipart.impl.MultiPartWriter;

public class MyClient {


    public static void main(String[] args) throws JSONException, IOException 
    {
        MyClient my_client = new MyClient();
        File file_upload = new File("local_file/file_name.pdf");
        my_client.sendFileJSON(file_upload);
    }


    private void sendFileJSON(File file_upload) throws JSONException, IOException{

        ClientConfig config = new DefaultClientConfig();
        Client client = Client.create(config);
        client.addFilter(new LoggingFilter());
        WebResource service = client.resource("my_rest_address_path");
        JSONObject data_file = new JSONObject();
        data_file.put("file_name", file_upload.getName());
        data_file.put("description", "Something about my file....");
        data_file.put("file", convertFileToString(file_upload));

        ClientResponse client_response = service.accept(MediaType.APPLICATION_JSON).post(ClientResponse.class, data_file);

        System.out.println("Status: "+client_response.getStatus());

        client.destroy();

    }


    //Convert my file to a Base64 String
    private String convertFileToString(File file) throws IOException{
        byte[] bytes = Files.readAllBytes(file.toPath());   
        return new String(Base64.encode(bytes));
    }

}
3
  • What type is dados? Commented Sep 3, 2013 at 19:33
  • I'm sorry... i forgot to rename, but dados = my_data Commented Sep 4, 2013 at 11:27
  • Was it meant to be Base64.getDecoder().decode(file_string) perhaps?
    – Niccolò
    Commented May 19, 2016 at 15:32

6 Answers 6

8

You should convert the file data to Base64 encoding and then transfer it, e.g. like this:

byte[] bytes = Files.readAllBytes(file_upload.toPath());
dados.put("File", DatatypeConverter.printBase64Binary(bytes));
3
  • 2
    Nope. Looks strange, that's right, but it does what it should: convert a byte array to Base64. Use parseBase64Binary(String) to convert a Base64 String to a byte array. Commented Sep 3, 2013 at 19:58
  • Thanks, good to know that we need use Base64!! I tried making that without using Base64, but I had problems with pdf files. Commented Sep 4, 2013 at 13:01
  • 3
    @MoritzPetersen, is that a good pratice? I think it is not a good idea send a file as string embedded at json
    – well
    Commented Oct 22, 2015 at 20:32
3
@POST
@Path("/uploadWeb")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response uploadWeb(  @FormDataMultiPart("image")     InputStream uploadedInputStream,
                @FormDataParam("image")     FormDataContentDisposition fileDetail ) {

    int read = 0;
    byte[] bytes = new byte[1024];
    while ((read = uploadedInputStream.read(bytes)) != -1)
        System.out.write(bytes, 0, read);
    return Response.status(HttpStatus.SC_OK).entity(c).build();
 }

and of the client side (see this post):

HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(url);
FileBody fileContent= new FileBody(new File(fileName));
StringBody comment = new StringBody("Filename: " + fileName);
MultipartEntity reqEntity = new MultipartEntity();
reqEntity.addPart("file", fileContent);
httppost.setEntity(reqEntity);
HttpResponse response = httpclient.execute(httppost);
HttpEntity resEntity = response.getEntity();
6
  • How is that converting any JSON? Commented Sep 3, 2013 at 20:12
  • 1
    That's the way to upload file data, read the question, he wants to send the data but choose the wrong way to do it. Commented Sep 3, 2013 at 20:46
  • Why is that the wrong way? I thought that send all information that I want inside a json should be easier... Commented Sep 4, 2013 at 12:50
  • 2
    the reasons: 1. There is more payload for sending encoded file then up stream it. 2. It is more REST way of doing it. 3. The REST API will be valid for javascript as well 4. Save RAM while not been required to load the uploaded data into memory. I have implemented this numerous times successfully, and I can not see a reason for creating a big pay-loaded JSON. Commented Sep 5, 2013 at 10:53
  • I understood. Thanks for helping! I made a new implementation using it... but I had some problems using that annotation @FormDataParam ("image"), so I changed the parammeter to FormDataMultiPart and it worked. Commented Sep 16, 2013 at 13:34
2

I know its an old post but I just thought I'd add a little to avoid the dependancy on external librarys.

//Convert my file to a Base64 String
public static final String convertFileToString(File file) throws IOException{
   byte[] bytes = Files.readAllBytes(file.toPath());   
   return new String(Base64.getEncoder().encode(bytes));
}

//Convert a Base64 string and create a file
public static final void convertFile(String file_string, String file_name) throws IOException{
   byte[] bytes = Base64.getDecoder().decode(file_string);
   File file = new File("local_path/"+file_name);
   FileOutputStream fop = new FileOutputStream(file);
   fop.write(bytes);
   fop.flush();
   fop.close();
}
0

I don't know what dados is referring to, possibly a Map<String, String>, but I think you want to be using the JSONObject you just created

JSONObject my_data = new JSONObject();
File file_upload = new File("C:/hi.txt");
my_data.put("User", "Beth");
my_data.put("Date", "22-07-2013");
my_data.put("File", file_upload);

However this is useless and might not be doing what you think. A File object doesn't hold a file, it holds the path to the file, ie. C:/hi.txt. If that's what you put in your JSON, it'll produce

{"File" : "C:/hi.txt"}

It won't contain the file content.

So you might as well just put the file path directly

JSONObject my_data = new JSONObject();
my_data.put("User", "Beth");
my_data.put("Date", "22-07-2013");
my_data.put("File", "C:/hi.txt");

If you're trying to do a file upload with JSON, one way is to read the bytes from the file with Java 7's NIO

byte[] bytes = Files.readAllBytes(file_upload .toPath());

Base64 encode those bytes and write them as a String in the JSONObject. Using Apache Commons Codec

Base64.encodeBase64(bytes);
my_data.put("File", new String(bytes));
2
  • No need to use Commons Codec; DatatypeConverter is part of the standard (JAXB). Commented Sep 3, 2013 at 19:47
  • Thanks! I used com.sun.jersey.core.util.Base64 that has Base64.encode(bytes) and Base64.decode(bytes). Commented Sep 4, 2013 at 12:53
0

Kindly change the machine address from localhost to ip address you want your client to connect with to call below mentioned service.

**CLIENT TO CALL REST WEBSERVICE**


    package in.india.client.downloadfiledemo;

    import java.io.BufferedInputStream;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.FileOutputStream;
    import java.io.IOException;

    import javax.ws.rs.core.MediaType;
    import javax.ws.rs.core.Response.Status;

    import com.sun.jersey.api.client.Client;
    import com.sun.jersey.api.client.ClientHandlerException;
    import com.sun.jersey.api.client.ClientResponse;
    import com.sun.jersey.api.client.UniformInterfaceException;
    import com.sun.jersey.api.client.WebResource;
    import com.sun.jersey.multipart.BodyPart;
    import com.sun.jersey.multipart.MultiPart;

    public class DownloadFileClient {

        private static final String BASE_URI = "http://localhost:8080/DownloadFileDemo/services/downloadfile";

        public DownloadFileClient() {

            try {
                Client client = Client.create();
                WebResource objWebResource = client.resource(BASE_URI);
                ClientResponse response = objWebResource.path("/")
                        .type(MediaType.TEXT_HTML).get(ClientResponse.class);

                System.out.println("response : " + response);
                if (response.getStatus() == Status.OK.getStatusCode()
                        && response.hasEntity()) {
                    MultiPart objMultiPart = response.getEntity(MultiPart.class);
                    java.util.List<BodyPart> listBodyPart = objMultiPart
                            .getBodyParts();
                    BodyPart filenameBodyPart = listBodyPart.get(0);
                    BodyPart fileLengthBodyPart = listBodyPart.get(1);
                    BodyPart fileBodyPart = listBodyPart.get(2);

                    String filename = filenameBodyPart.getEntityAs(String.class);
                    String fileLength = fileLengthBodyPart
                            .getEntityAs(String.class);
                    File streamedFile = fileBodyPart.getEntityAs(File.class);

                    BufferedInputStream objBufferedInputStream = new BufferedInputStream(
                            new FileInputStream(streamedFile));

                    byte[] bytes = new byte[objBufferedInputStream.available()];

                    objBufferedInputStream.read(bytes);

                    String outFileName = "D:/"
                            + filename;
                    System.out.println("File name is : " + filename
                            + " and length is : " + fileLength);
                    FileOutputStream objFileOutputStream = new FileOutputStream(
                            outFileName);
                    objFileOutputStream.write(bytes);
                    objFileOutputStream.close();
                    objBufferedInputStream.close();
                    File receivedFile = new File(outFileName);
                    System.out.print("Is the file size is same? :\t");
                    System.out.println(Long.parseLong(fileLength) == receivedFile
                            .length());
                }
            } catch (UniformInterfaceException e) {
                e.printStackTrace();
            } catch (ClientHandlerException e) {
                e.printStackTrace();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

        }

        public static void main(String... args) {
            new DownloadFileClient();
        }

    }


**SERVICE TO RESPONSE CLIENT** 

package in.india.service.downloadfiledemo;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import com.sun.jersey.multipart.MultiPart;

@Path("downloadfile")
@Produces("multipart/mixed")
public class DownloadFileResource {

    @GET
    public Response getFile() {

        java.io.File objFile = new java.io.File(
                "D:/DanGilbert_2004-480p-en.mp4");
        MultiPart objMultiPart = new MultiPart();
        objMultiPart.type(new MediaType("multipart", "mixed"));
        objMultiPart
                .bodyPart(objFile.getName(), new MediaType("text", "plain"));
        objMultiPart.bodyPart("" + objFile.length(), new MediaType("text",
                "plain"));
        objMultiPart.bodyPart(objFile, new MediaType("multipart", "mixed"));

        return Response.ok(objMultiPart).build();

    }

}

**JAR NEEDED** 

jersey-bundle-1.14.jar
jersey-multipart-1.14.jar
mimepull.jar

**WEB.XML**


<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    id="WebApp_ID" version="2.5">
    <display-name>DownloadFileDemo</display-name>
    <servlet>
        <display-name>JAX-RS REST Servlet</display-name>
        <servlet-name>JAX-RS REST Servlet</servlet-name>
        <servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
        <init-param>
             <param-name>com.sun.jersey.config.property.packages</param-name> 
             <param-value>in.india.service.downloadfiledemo</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>JAX-RS REST Servlet</servlet-name>
        <url-pattern>/services/*</url-pattern>
    </servlet-mapping>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>
0
-1

You need to convert your file to a byte array and then send it within the json.

see the following:send file to webservice

2
  • I thought this solution complicated... Is this solution better than the others? I converted my file to bytes and then to string Base64 and put it in my json, so my web service takes that string and decode Base64 to bytes and then I create my file. Commented Sep 4, 2013 at 12:58
  • Just an example of what you have already discovered you need to do to pass your file.
    – Dan Rowe
    Commented Sep 4, 2013 at 13:13

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