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Téléchargement de fichiers à l'aide de l'API Rest dans Java

Je suis nouveau sur REST API. Je veux télécharger le fichier sélectionné par l'utilisateur vers le chemin fourni par l'utilisateur (chemin distant ou local) en utilisant REST API. Mon fichier html contient 1 zone de texte et 1 sélecteur de fichier. L'utilisateur entrera FilePath (emplacement du dossier de l'ordinateur local ou distant) dans la zone de texte. Veuillez suggérer comment résoudre ce problème.

Voici mon code:

FileUpload.html::

<body>
    <form action="rest/file/upload" method="post" enctype="multipart/form-data">
        <p>
            Select a file : <input type="file" name="file" size="45" />
        </p>
        <p>Target Upload Path : <input type="text" name="path" /></p>
        <input type="submit" value="Upload It" />
   </form>
</body>

ploadFileService.Java

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

    @POST
    @Path("/upload")
    @Consumes(MediaType.MULTIPART_FORM_DATA)
    public Response uploadFile(
            @FormDataParam("file") InputStream uploadedInputStream,
            @FormDataParam("file") FormDataContentDisposition fileDetail,
            @FormParam("path") String path) {

        /*String uploadedFileLocation = "d://uploaded/"                                                                 + fileDetail.getFileName();*/

        /*String uploadedFileLocation = //10.217.14.88/Installables/uploaded/"                                                                  + fileDetail.getFileName();*/
        String uploadedFileLocation = path
                + fileDetail.getFileName();

        // save it
        writeToFile(uploadedInputStream, uploadedFileLocation);

        String output = "File uploaded to : " + uploadedFileLocation;

        return Response.status(200).entity(output).build();

    }

    // save uploaded file to new location
    private void writeToFile(InputStream uploadedInputStream,
            String uploadedFileLocation) {

        try {
            OutputStream out = new FileOutputStream(new File(
                    uploadedFileLocation));
            int read = 0;
            byte[] bytes = new byte[1024];

            out = new FileOutputStream(new File(uploadedFileLocation));
            while ((read = uploadedInputStream.read(bytes)) != -1) {
                out.write(bytes, 0, read);
            }
            out.flush();
            out.close();
        } catch (IOException e) {

            e.printStackTrace();
        }

    }

}

Web.xml

<display-name>JAXRSFileUploadJerseyExample</display-name>
<servlet>
    <servlet-name>jersey-serlvet</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>com.mkyong.rest</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>jersey-serlvet</servlet-name>
    <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

Exception:

HTTP Status 500 - com.Sun.jersey.api.container.ContainerException: Exception obtaining parameters
type Exception report
message com.Sun.jersey.api.container.ContainerException: Exception obtaining parameters
description The server encountered an internal error that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: com.Sun.jersey.api.container.ContainerException: Exception obtaining parameters
        com.Sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.Java:425)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:537)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:699)
        javax.servlet.http.HttpServlet.service(HttpServlet.Java:728)
root cause
com.Sun.jersey.api.container.ContainerException: Exception obtaining parameters
        com.Sun.jersey.server.impl.inject.InjectableValuesProvider.getInjectableValues(InjectableValuesProvider.Java:54)
        com.Sun.jersey.multipart.impl.FormDataMultiPartDispatchProvider$FormDataInjectableValuesProvider.getInjectableValues(FormDataMultiPartDispatchProvider.Java:125)
        com.Sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$EntityParamInInvoker.getParams(AbstractResourceMethodDispatchProvider.Java:153)
        com.Sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.Java:203)
        com.Sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.Java:75)
        com.Sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.Java:288)
        com.Sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.Java:147)
        com.Sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.Java:108)
        com.Sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.Java:147)
        com.Sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.Java:84)
        com.Sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.Java:1469)
        com.Sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.Java:1400)
        com.Sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.Java:1349)
        com.Sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.Java:1339)
        com.Sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.Java:416)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:537)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:699)
        javax.servlet.http.HttpServlet.service(HttpServlet.Java:728)
root cause
Java.lang.IllegalStateException: The @FormParam is utilized when the content type of the request entity is not application/x-www-form-urlencoded
        com.Sun.jersey.server.impl.model.parameter.FormParamInjectableProvider$FormParamInjectable.getValue(FormParamInjectableProvider.Java:81)
        com.Sun.jersey.server.impl.inject.InjectableValuesProvider.getInjectableValues(InjectableValuesProvider.Java:46)
        com.Sun.jersey.multipart.impl.FormDataMultiPartDispatchProvider$FormDataInjectableValuesProvider.getInjectableValues(FormDataMultiPartDispatchProvider.Java:125)
        com.Sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$EntityParamInInvoker.getParams(AbstractResourceMethodDispatchProvider.Java:153)
        com.Sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.Java:203)
        com.Sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.Java:75)
        com.Sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.Java:288)
        com.Sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.Java:147)
        com.Sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.Java:108)
        com.Sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.Java:147)
        com.Sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.Java:84)
        com.Sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.Java:1469)
        com.Sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.Java:1400)
        com.Sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.Java:1349)
        com.Sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.Java:1339)
        com.Sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.Java:416)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:537)
        com.Sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.Java:699)
        javax.servlet.http.HttpServlet.service(HttpServlet.Java:728)
javaweb-servicesrestfile-uploadjersey
9
JLyon

J'ai mis à jour la signature de la méthode dans la classe ci-dessous et son bon fonctionnement. Au lieu de @FormParam, J'ai utilisé @FormDataParam("path") Chemin de chaîne et cela a résolu mon problème. Voici le code mis à jour:

import Java.io.File;
import Java.io.FileOutputStream;
import Java.io.IOException;
import Java.io.InputStream;
import Java.io.OutputStream;

import javax.ws.rs.Consumes;
import javax.ws.rs.FormParam;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import com.Sun.jersey.core.header.FormDataContentDisposition;
import com.Sun.jersey.multipart.FormDataParam;

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

@POST
@Path("/upload")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response uploadFile(
        @FormDataParam("file") InputStream uploadedInputStream,
        @FormDataParam("file") FormDataContentDisposition fileDetail,
        @FormDataParam("path") String path) {


    // Path format //10.217.14.97/Installables/uploaded/
    System.out.println("path::"+path);
    String uploadedFileLocation = path
            + fileDetail.getFileName();

    // save it
    writeToFile(uploadedInputStream, uploadedFileLocation);

    String output = "File uploaded to : " + uploadedFileLocation;

    return Response.status(200).entity(output).build();

}

// save uploaded file to new location
private void writeToFile(InputStream uploadedInputStream,
        String uploadedFileLocation) {

    try {
        OutputStream out = new FileOutputStream(new File(
                uploadedFileLocation));
        int read = 0;
        byte[] bytes = new byte[1024];

        out = new FileOutputStream(new File(uploadedFileLocation));
        while ((read = uploadedInputStream.read(bytes)) != -1) {
            out.write(bytes, 0, read);
        }
        out.flush();
        out.close();
    } catch (IOException e) {

        e.printStackTrace();
    }

   }

   }
8
JLyon

Une autre solution possible

@Consume l'annotation et la définit sur le flux d'octets d'application. Utilisez la méthode PUT http. Ensuite, dans le client, lisez les octets du fichier et téléchargez.

Mon exemple de code pour un service REST pour compresser un fichier est ici - https://stackoverflow.com/a/32253028/15789

J'espère que cela t'aides.

1
RuntimeException