Java中图像的多部分上传

我正试图通过Java代码将文件附加到。我使用多部分数据上传。我试过上传文本文件，效果很好。当我尝试jpg文件时，响应代码是200，但是上传的文件有一些问题。它说文件已损坏

用于将图像转换为字节数组的代码

             byte[] bFile = new byte[(int) file.length()];
             fileInputStream = new FileInputStream(file);
             int bytesAvailable = fileInputStream.available();
             int maxBufferSize = 4096;

             byte[] buffer = new byte[bytesAvailable];
             ByteArrayOutputStream bos = new ByteArrayOutputStream();

             int bytesRead = fileInputStream.read(buffer, 0, bytesAvailable);

             while (bytesRead > 0) {
                bos.write(buffer, 0, bytesAvailable);
                 bytesAvailable = fileInputStream.available();
                 bytesAvailable = Math.min(bytesAvailable, maxBufferSize);
                 bytesRead = fileInputStream.read(buffer, 0, bytesAvailable);
             }
             bFile = bos.toByteArray();

上传的代码

        String contentDisposition = "Content-Disposition: form-data; name=\"file\"; filename=\"" + file.getName() + "\"";
        String contentType = "Content-Type: image/jpg";         
        String BOUNDARY = "*****";
        HttpsURLConnection connection;
        String CRLF = "\r\n";   
        StringBuffer requestBody = new StringBuffer();
        requestBody.append("--");
        requestBody.append(BOUNDARY);
        requestBody.append(CRLF);
        requestBody.append(contentDisposition);
        requestBody.append(CRLF);
        requestBody.append(contentType);
        requestBody.append(CRLF);
        requestBody.append(CRLF);
        requestBody.append(new String(bFile));
        requestBody.append(CRLF);
        requestBody.append("--");
        requestBody.append(BOUNDARY);
        requestBody.append("--");

        URL obj = new URL("url");
        connection = (HttpsURLConnection) obj.openConnection();
        connection.setRequestMethod("POST");
        connection.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
        connection.setRequestProperty("User-Agent", "Mozilla/5.0");
        connection.setRequestProperty("Accept","*/*");
        connection.setRequestProperty("Authorization", strEncoded);
        connection.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + BOUNDARY);

        connection.setDoOutput(true);
        connection.setDoInput(true);
        connection.setUseCaches(false);
        DataOutputStream wr = new DataOutputStream(connection.getOutputStream());
        wr.writeBytes(requestBody.toString());
        wr.flush();
        wr.close();

请让我知道我发送的图像字节数组是否有任何问题

请检查所附的屏幕截图以获取错误消息

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谢谢。

您读取文件字节的代码很容易出错，请查看您的答案

您不能只在请求正文中添加字节

requestBody.append（新字符串（bFile））

这会将图像字节转换为您不想要的字符-您需要在从图像文件读取它们时传输字节

使用ApacheHttpClient之类的工具，而不是手动执行此操作。它可以处理一些细节，比如在http post中正确放置文件字节。见官方或查看中的代码。
谢谢@vanOekal。问题在于发送字节。我将代码替换为
while（bytesRead>0）{write（buffer，0，bytesavable）；bytesavable=fileInputStream.available（）；bytesavable=Math.min（bytesavable，maxBufferSize）；bytesRead=fileInputStream.read（buffer，0，bytesavable）；}
现在可以正常工作了。