Question

我尝试为我的网络服务编写一个上传post方法的图像文件。这是我的帖子方法。图像文件可以上传到post方法，但不能转换为Image类型。

@POST
@Path("/upload")
@Consumes(MediaType.MULTIPART_FORM_DATA)
@Produces("text/html")
public Response uploadFile(@FormDataParam("file") File file2) throws IOException {
    InputStream IS = null;

    String output = "";

    try {
        IS = new FileInputStream(file2);
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } finally {

    }


    try {
        if (file2 != null && IS != null) {
            Image img = ImageIO.read(IS);
            if (img != null) {
                output = "image file transmission sucessed";

            } else {
                String out = convertStreamToString(IS);
                output = "file uploaded into post method, however can not transfer it into image type "+
                "\n"+ out;
            }

        } else if (file2 == null) {
            output = "the file uploaded into post method is null";
        }

    } catch (IOException e) {
        e.printStackTrace();

    }

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

}

static String convertStreamToString(java.io.InputStream is) {
    java.util.Scanner s = new java.util.Scanner(is).useDelimiter("\\A");
    return s.hasNext() ? s.next() : "";
}

上传到post方法的＆＃34;文件无法将其传输到图像类型＆＃34; +＆＃34; \ n＆＃34; + out;消息显示。我相信的原因是inputStream包含extral文件信息+图像的内容。当我尝试将inputStream转换回Image时，我需要找到一种方法来摆脱传递的额外信息。

这是我的新版本：

@POST
@Path("/images")
@Consumes(MediaType.MULTIPART_FORM_DATA)
public Response imageUpload(
        @FormDataParam("image") InputStream hereIsImage,
        @FormDataParam("image") FormDataContentDisposition hereIsName) {
    String path = "f://";
    if (hereIsName.getSize() == 0) {
        return Response.status(500).entity("image parameter is missing")
                .build();
    }
    String name = hereIsName.getFileName();
    path += name;

    try {
        OutputStream out = new FileOutputStream(new File(path));
        int read;
        byte[] bytes = new byte[1024];
        while ((read = hereIsImage.read(bytes)) != -1) {
            out.write(bytes, 0, read);
        }
        out.flush();
        out.close();
    } catch (IOException e) {
        return Response.status(500)
                .entity(name + " was not uploaded\n" + e.getMessage())
                .build();
    }
    return Response.status(200).entity(name + " was uploaded").build();
}

但是，当我上传图片时，会弹出一个错误：

[ERROR]处理au.edu.rmit.srtwebservice.util.rest.testWS类时发生异常。该类被忽略。 COM /太阳/球衣/核心/报头/ FormDataContentDisposition

testWS.calss是我的方法所在。

Answer 1

public Response uploadFile(@FormDataParam("file") File file2)

File输入可能无效，因为您最有可能从客户端发送八位字节流。因此，尝试使用InputStream作为输入类型，并希望它可以工作。

public Response uploadFile(@FormDataParam("file") InputStream file2)

png文件上传Restful Web Service java

1 个答案: