泽西岛客户端下载并保存文件

Question

我是球衣/ JAX-RS实施的新手。请在下面找到我的泽西岛客户代码以下载文件：

 Client client = Client.create();
 WebResource wr = client.resource("http://localhost:7070/upload-0.0.1-SNAPSHOT/rest/files/download");
 Builder wb=wr.accept("application/json,application/pdf,text/plain,image/jpeg,application/xml,application/vnd.ms-excel");
 ClientResponse clientResponse= wr.get(ClientResponse.class);
 System.out.println(clientResponse.getStatus());
 File res= clientResponse.getEntity(File.class);
 File downloadfile = new File("C://Data/test/downloaded/testnew.pdf");  
 res.renameTo(downloadfile);
 FileWriter fr = new FileWriter(res);
 fr.flush();

我的服务器端代码是：

@Path("/download")
    @GET
    @Produces({"application/pdf","text/plain","image/jpeg","application/xml","application/vnd.ms-excel"})
    public Response getFile()
    {

        File download = new File("C://Data/Test/downloaded/empty.pdf");
        ResponseBuilder response = Response.ok((Object)download);
        response.header("Content-Disposition", "attachment; filename=empty.pdf");
        return response.build();
    }

在我的客户代码中，我收到200
OK的响应，但是我无法将文件保存在硬盘上。在下面的行中，我提到了需要保存文件的路径和位置。不知道这里出了什么问题，将不胜感激。谢谢！！

File downloadfile = new File("C://Data/test/downloaded/testnew.pdf");

Answer 1

我不知道是否让Jersey让您简单地回应一个文件，就像这里一样：

File download = new File("C://Data/Test/downloaded/empty.pdf");
ResponseBuilder response = Response.ok((Object)download);

你 可以 肯定使用StreamingOutput响应从服务器发送的文件，就像这样：

StreamingOutput stream = new StreamingOutput() {
    @Override
    public void write(OutputStream os) throws IOException,
    WebApplicationException {
        Writer writer = new BufferedWriter(new OutputStreamWriter(os));

        //@TODO read the file here and write to the writer

        writer.flush();
    }
};

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

并且您的客户希望读取流并将其放入文件中：

InputStream in = response.getEntityInputStream();
if (in != null) {
    File f = new File("C://Data/test/downloaded/testnew.pdf");

    //@TODO copy the in stream to the file f

    System.out.println("Result size:" + f.length() + " written to " + f.getPath());
}