I use javamail to get message, when I get the message i have:
com.sun.mail.util.BASE64DecoderStream,
I know that is part of multipart message, in the source of message I have
Content-Type: image/png; name=index_01.png
Content-Transfer-Encoding: base64
How encode this message??
edit:
I have that code:
else if (mbp.getContent() instanceof BASE64DecoderStream){
InputStream is = null;
ByteArrayOutputStream os = null;
is = mbp.getInputStream();
os = new ByteArrayOutputStream(512);
int c = 0;
while ((c = is.read()) != -1) {
os.write(c);
}
System.out.println(os.toString());
}
And that code return strange string, for example:
Ř˙á?Exif??II*????????????˙ě?Ducky???????˙á)
com.sun.mail.util.BASE64DecoderStream is platform dependent. You cannot rely on that always being the type of class that handles base64 decoding.
Rather the javamail APIs already support decoding for you:
// part is instanceof javax.mail.Part
ByteArrayOutputStream bos = new ByteArrayOutputStream();
part.getDataHandler().writeTo(bos);
String decodedContent = bos.toString()
What are you expecting when you read the contents of an image part? The image is stored in the message in an encoded format, but JavaMail is decoding the data before returning the bytes to you. If you store the bytes in a file, you can display the image with many image viewing/editing applications. If you want to display them with your Java program, you'll need to convert the bytes to an appropriate Java Image object using (e.g.) APIs in the java.awt.image package.
That Sun's base 64 encoder is in the optional package and can be moved or renamed at any time without warning, also may be missing in alternative Java runtimes, also access to these packages may be disabled. It is much better not to rely on it.
I would say, use Base64 from Apache Commons instead, should do the same. Hope you can rebuild and fix the source code.
Related
I am using Node Red to implement a web service and I am racking my brains to convert a base64 string to byte array (uint8array) or convert buffer to uint8array.
One "node" of my node-red flow outputs an image as a buffer or a base64 string.
I need to pass the responsed image into a web service which requires an uint8array base image.
There is a lot of answers using atob and btoa but node red does not support it.
Below is the output buffer format that I need to convert
And this is the buffer format what I want:
Here is the documentation of the web service I want to call:
https://demous-cdb.thereforeonline.com/theservice/v0001/restun/help/operations/CreateDocument
I have tryed a lot of ways:
function toArrayBuffer(myBuf) {
var myBuffer = new ArrayBuffer(myBuf.length);
var res = new Uint8Array(myBuffer);
for (var i = 0; i < myBuf.length; ++i) {
res[i] = myBuf[i];
}
return myBuffer;
}
=====
Also tryed to use...
var buf = Buffer.from(b64string, 'base64')
The solution above does not generates an uint8array
Do you have any idea?
The base64 node (https://flows.nodered.org/node/node-red-node-base64) should convert the base64 to buffer which you can then use as input to what ever node you are using to send to the webservice.
The NodeJS Buffer is a subclass of Uint8Array, they are just ways to represent collections of bytes.
I am sending DICOM images to my API by encoding as base64 from the frontend, which is in Angular CLI. Also, I have Rest API to get those encoded DICOM images and decode them back before had some process with them. But after decoding the DICOM image into the memory stream, metadata of DICOM images are lost. It is appreciatable if I got a better solution. Please find my codes below.
//Angular code
var file = event.dataTransfer ? event.dataTransfer.files[i] :
event.target.files[0];
//var pattern = /.dcm/;
var reader = new FileReader();
reader.onload = this._handleReaderLoaded.bind(this);
reader.readAsDataURL(file);
//Web API Code
[HttpPost("UploadFile/{Id}")]
public async Task<IActionResult> UploadFile(int Id, [FromBody] DICOMFiles
dicomfiles)
{
String base64Encoded = encodedImage;
string output =
encodedImage.Substring(encodedImage.IndexOf(',') + 1);
byte[] data = Convert.FromBase64String(output);
MemoryStream stream = new MemoryStream(data);
client.UploadFile(stream, "Projects/test_images/Test.dcm");
}
At last, I found a solution for this. The problem is not about decode from base64. The actual problem is with the client.UploadFile() method call.
Before using the client.uploadfile(), we need to make sure that the memory stream object is pointing to position "0". This will allow the client.UploadFile() method to create and write all the content of the mentioned file from the start of the byte[] array. we can do this as mentioned below.
stream.Position = 0;
I am using the following code to encode the SAMLRequest value to the endpoint, i.e. the XYZ when calling https://login.microsoftonline.com/common/saml2?SAMLRequest=XYZ.
Is this the correct way to encode it?
private static string DeflateEncode(string val)
{
var memoryStream = new MemoryStream();
using (var writer = new StreamWriter(new DeflateStream(memoryStream, CompressionMode.Compress, true), new UTF8Encoding(false)))
{
writer.Write(val);
writer.Close();
return Convert.ToBase64String(memoryStream.GetBuffer(), 0, (int)memoryStream.Length, Base64FormattingOptions.None);
}
}
If you just want to convert string to a base64 encoded string, then you can use the following way:
var encoded = Convert.ToBase64String(System.Text.Encoding.Default.GetBytes(val));
Console.WriteLine(encoded);
return encoded;
Yes, that looks correct for the Http Redirect binding.
But don't do this yourself unless you really know what you are doing. Sending the AuthnRequest is the simple part. Correctly validating the received response, including guarding for Xml signature wrapping attacks is hard. Use an existing library, there are both commercial and open source libraries available.
I'm new to Windows phone 8 Dev and C#. I try to get String from remote server. This is my code:
var client = new HttpClient();
var response = await client.GetAsync(MyUrl);
string charset = GetCharset(response.Content.Headers.ContentType.ToString());
Debug.WriteLine("charset: " + charset); \\debug show: charset: ISO-8859-1
var bytesCharset = await response.Content.ReadAsByteArrayAsync();
Debug.WriteLine(Encoding.UTF8.GetString(bytesCharset,0,bytesCharset.Length));
//Debug show: `m\u1EF9 t�m`
m\u1EF9 t�m is what I got, but I expect it's Vietnamese: Mỹ Tâm. Can anyone give me an idea to get expected result? (I think the bytes is encoded in IOS-8859-1).
Encoding.UTF8 should be interpreting your data correctly, as ISO-8859-1 is a subset of UTF-8. However, so that other encodings are handled transparently, it is probably better to use HttpContent's ReadAsStringAsync() method instead of ReadAsByteArrayAsync().
I suspect you have the correct string there but your debug window simply cannot display those two unicode characters properly.
You can use the static GetEncoding method to request a specificy codepage.
e.g.:
var encoding = Encoding.GetEncoding("ISO-8859-1");
Finally I found the solution. After using Json.Net to parse json from remote server, my problem's gone, and I can get expected result:
JArray jArray = JArray.Parse(isoText);
String exptectedText= jArray[1].ToString();
Actually, I dont know why my code works :( Thank you anyway!
I want to implement a behavior similar to Whatsapp, where when the user can upload an image. I tried opening the images in my app, but if the image is too large, I will have an out of memory error.
To solve this, I'm opening forwarding the images to be open in the phone's native image viewer using the platformRequest() method.
However, I want to know how is it Whatsapp modifies the phone's native image viewer to add a "Select" button, with which the user selects the image he wants to upload. How is that information sent back to the J2ME application and how is the image resized?
Edit:
I tried this in two different ways, both of which gave me the OOME.
At first, I tried the more direct method:
FileConnection fc = (FileConnection) Connector.open("file://localhost/" + currDirName + fileName);
if (!fc.exists()) {
throw new IOException("File does not exists");
}
InputStream fis = fc.openInputStream();
Image im = Image.createImage(fis);
fis.close();
When that didn't work, I tried a more "manual" approach, but that gave me an error as well.
FileConnection fc = (FileConnection) Connector.open("file://localhost/" + currDirName + fileName);
if (!fc.exists()) {
throw new IOException("File does not exists");
}
InputStream fis = fc.openInputStream();
ByteArrayOutputStream file = new ByteArrayOutputStream();
int c;
byte[] data = new byte[1024];
while ((c = fis.read(data)) != -1) {
file.write(data, 0, c);
}
byte[] fileData = null;
fileData = file.toByteArray();
fis.close();
fc.close();
file.close();
Image im = Image.createImage(fileData, 0, fileData.length);
When I call the createImage method, the out of memory error occurs in both cases.
This varies with the devices. An E72 gives me the error with 3MB images, while a newer device will give me the error with images larger than 10MBs.
MIDP 2 (JSR 118) does not have API for that, you need to find another way to handle big images.
As for WhatsApp, it looks like they do not rely on MIDP in supporting this functionality. If you check the Wikipedia page you'll note that they don't claim general Java ME as supported platform, but instead, list narrower platforms like Symbian, S40, Blackberry etc.
This most likely means that they implement "problematic features" like one you're asking about using platform-specific API of particular target devices, having essentially separate projects / releases for every platform listed.
If this feature is really necessary in your application, you likely will have to do something like this.
In this case, consider also encapsulating problematic features in a way to make it easier to switch just part of your source code when building it for different platforms. For example, Class.forName(String) can be used to load platform specific implementation depending on target platform.
//...
Image getImage(String resourceName) {
// ImageUtil is an interface with method getImage
ImageUtil imageUtil = (ImageUtil) Class.forName(
// get platform-specific implementation, eg
// "mypackage.platformspecific.s40.S40ImageUtil"
// "mypackage.platformspecific.bb.BBImageUtil"
// "mypackage.platformspecific.symbian.SymbialImageUtil"
"mypackage.platformspecific.s40.S40ImageUtil");
return imageUtil.getImage(resourceName);
}
//...