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How to read DICOM string value with backslash (VR=LO, Value="0.4323\0.2325")?

Our C++ software use ITK to write DICOM files. In it we have a Private Tag with LO (Long String) as VR and 2 decimal values as value like 0.3234\0.34223.
The LO choice is inherent to ITK.
In other java application, I use dcm4che3 to read/write them. Since it respects the DICOM protocol, backslash are forbidden, and dcm4che interpret the value as "0.3234" and never reach the second value.
All DICOM viewer applications I use can display this value.
So my question is: Is there a trick in dcm4che to read this complete value as a string "0.3234\0.34223" despite the presence of a backslash?
Below, the code I use:
public DicomInfo uploadFile(MultipartFile file) throws IOException, ParseException {
DicomInfo infos = new DicomInfo();
Attributes attrs = readDicomAttributes(file);
infos.setTags(toAttributesObject(attrs).toString());
}
private static JsonObject toAttributesObject(Attributes targetSeriesAttrs)
{
StringWriter strWriter = new StringWriter();
JsonGenerator gen = Json.createGenerator(strWriter);
JSONWriter writer = new JSONWriter(gen);
writer.write(targetSeriesAttrs);
gen.flush();
gen.close();
return Json.createReader(new
StringReader(strWriter.toString())).readObject();
}
public Attributes readDicomAttributes(MultipartFile file) throws IOException
{
DicomInputStream dis = new DicomInputStream(file.getInputStream());
Attributes dataSet = dis.readDataset(-1, Tag.PixelData);
Attributes fmi = dis.readFileMetaInformation();
dis.close();
fmi.addAll(dataSet);
return fmi;
}
In the JSON I get for this tag:
\"00110013\":{\"vr\":\"LO\",\"Value\":[\"0.4323\"]},
As you can see it is LO and the second part is already lost.
The method I use to get the specific attribute:
attr.getStrings(0x00110013)
send back a table with only one value, 0.4323.
The problem happens during the readDataSet function.
When I open tags with software like free dicom viewer, I have the complete data, so data is here.
Ok I found the source of the problem... It is the addAll fmi.addAll(dataSet);
In dataSet, getStrings works perfectly. In fmi after addAll, the attributes lost the second value.
So my problem is to solve this addAll issue now: dcm4che3 java lib: Attributes.addAll method seems to lost multiple LO values

See answer from Paolo, and please believe us that the backslash is not a violation of the VR. Like he said, the attribute is 2-dimensional, i.e. it has two values of VR LO which are separated by the backslash.
I know a bit about the dcm4che project and the people behind it, and it is nearly unthinkable to me that it is generally incapable of handling this.
I strongly suspect that your problem is related to the fact that your attribute is private. That is, without any additional information to the tag and its value, dcm4che (and any other product) can never know that the attribute's value is encoded as VR LO (Long String).
The default transfer syntax in DICOM is Implicit Little Endian. This means, that the dataset does not convey an explicit information about the VR of the attributes in the dataset. This information is implicitly encoded by the Tag of the attribute, and the data dictionary (DICOM Part 6) must be used to look up the tag and obtain the corresponding VR. Obvioulsy this only works for well-known DICOM tags defined in the standard and fails for private ones.
So one option is to try encoding the dataset in Explicit Little Endian, which means that the VR is part of the attribute's encoding in the dataset. I would expect this to be sufficient.
Mature toolkits (like dcm4che) allow for extending the data dictionary by configuration, that is, you can extend the "official" data dictionary used by the tookit with your custom tag definitions - including the VR. So the tag can be looked up in the case that the VR is not explicitly given in the dataset itself.
Again, I am not an expert for dcm4che, but a quick search at google for "dcm4che private dictionary" yields this promising link.
I am more than confident that you can solve the problem in dcm4che and that you do not have to migrate to a different toolkit.

The solution of this problem is to write
dataSet.addAll(fmi);
return dataSet;
instead of
fmi.AddAll(dataSet);
return fmi;
since the addAll methods lost multiple values of private LO

LO can have multiple values separated by a backslash.
The DICOM standard says that in the VR "LO" the backslash cannot be used in values because it is used to separate the different elements.
In VRs that don't allow multiple elements then the backslash can be used in values.
So dcm4che is wrong here.

How to get custom extension attributes with microsoft graph api

I'm trying to get user details with microsoft-graph
I'm looking for a custom extension element in my response, such as "extension_3a4189d71ad149c6ab5e65ac45bd6add_MyAttribute1"
when I retrieve the response with String, I can see all the elements.
final ResponseEntity<String> response = restTemplate.exchange("http://graph.windows.net/tenant.com/me?api-version=1.6, HttpMethod.GET, new HttpEntity(headers),String.class);
But when I retrieve the response with com.microsoft.graph.models.extensions.User I can't see the extention anymore.
final ResponseEntity<User> response = restTemplate.exchange("http://graph.windows.net/tenant.com/me?api-version=1.6, HttpMethod.GET, new HttpEntity(headers),User.class);
How can I retrieve the custom extension in more elegant way than getting in String object and look for elements one by one?

because the extension attributes are specific to your tenant, that means its non standard, no out of the box "object class" in the sdk would contain it since it has the app id appended to it. extension_appid_attribname.
so you would have to handle it yourself. you can try to extend the user class and add a method to read or deserialize/map the json return from the graph api similar to what Hury suggested, or something to that effect. there won't likely be an out of the box solution for this.
there are also json libraries out there that may help you deserialize to a dynamic object of some sort, if you really didn't want to map the object manually.
Update:
I dug into this a bit further. I don't think its in extensions.extension however, I did find that in the java sdk you can access it . Here's the documentation: https://github.com/microsoftgraph/msgraph-sdk-java/wiki/Working-with-Open-Types
You would do something like
String ext =
user
.additionalDataManager()
.get("extension_2lkj3l12jl3j2kj3_yourproperty")
.getAsString();
Give that a try
Hopefully that helps.

Please use api
https://graph.microsoft.com/beta/users instead of https://graph.microsoft.com/v1.0/users api https://graph.microsoft.com/beta/users will return all data with custom data of users.

Get EC2 Instance XML Description using AWS Java SDK?

We have a scenario in which we need to retrieve the description info for EC2 instances running on AWS. To accomplish this, we are using the AWS Java SDK. In 90% of our use case, the com.amazonaws.services.ec2.model.Instance class is exactly what we need. However, there is also a small use-case where it would be beneficial to get the raw XML describing the instance. That is, the XML data before it is converted into the Instance object. Is there any way to obtain both the Instance object and the XML string using the AWS Java SDK? Is there a way to manually convert from one to the other? Or, would we be forced to make a separate call using HttpClient or something similar to get the XML data?

Make an EC2Client by adding request handler and override the beforeUnmarshalling() method like below
AmazonEC2ClientBuilder.standard().withRegion("us-east-1")
.withRequestHandlers(
new RequestHandler2() {
#Override
public HttpResponse beforeUnmarshalling(Request<?> request, HttpResponse httpResponse) {
// httpResponse.getContent() is the raw xml response from AWS
// you either save it to a file or to a XML document
return new HTTPResponse(...);
// if you consumed httpResponse.getContent(), you need to provide new HTTPResponse
}
}
).build():

If you have xml (e.g. from using AWS rest API directly), then you can use com.amazonaws.services.ec2.model.transform.* classes to convert xml to java objects. Unfortunately, it only provides classes required for SDK itself. So you, for example, can convert raw XML to an Instance using InstanceStaxUnmarshaller, but can't convert Instance to XML unless you write such converter.
Here is an example how to parse an Instance XML:
XMLEventReader eventReader = XMLInputFactory.newInstance().createXMLEventReader(new StringReader(instanceXml));
StaxUnmarshallerContext suc = new StaxUnmarshallerContext(eventReader, new TreeMap<>());
InstanceStaxUnmarshaller isu = new InstanceStaxUnmarshaller();
Instance i = isu.unmarshall(suc);
System.out.println(i.toString());
You probably can try to intercept raw AWS response, so that you can keep raw XML while still using SDK most of the time. But I wouldn't call that easy as it will require quite a bit of coding.

You could use JAXB.marshal like following. JAXB (Java Architecture for XML Binding) could convert Java object to / from XML file.
StringWriter sw = new StringWriter();
JAXB.marshal(instance, sw);
String xmlString = sw.toString();

You can use AWS rest API to replace Java SDK. A bonus will be slight performance gain because you'll not send statistic data to Amazon as the SDK does.

Using Protobuf to process a config file

I'm relatively new to Protobufs and I was wondering how I would use it to process a list of structures.
Lets say I have a configuration file that looks like this:
Bucket{
name = "A";
path = "~/Document/...";
traffic = 5;
}
Bucket{
name = "B";
path = "~/Document/...";
traffic = 6;
}
Bucket{
name = "C";
path = "~/Document/...";
traffic = 7;
}
etc etc.
So I am using a protobuf to essentially structure this for ease of use later in Java. I'm essentially trying to make a map in a map (a protobuf to help find the correct bucket, and then another map to obtain member attributes inside the bucket).
option java_outer_classname = "Buckets";
message Bucket {
required string name = 1;
required string path = 2;
optional int32 traffic = 3;
}
message BucketList {
required Bucket bucket = 1;
}
I'm confused on how I would link the two, as in, how would I pass the configuration file into the protobuf methods (after it compiles into a java class) and use to to access the bucket member to do stuff like say get the path from the bucket with the name A?
Thank you!

It's perfectly acceptable to use Protobuf as a mechanism to declare and parse a text configuration file. However, one must keep in mind that Protobuf's purpose is the declare the format of the file, be it plain text or its binary wire format. Higher level semantic constraints need to be enforced in custom application code, once the configuration has been read.

You've got the wrong idea of what protobuf is used for, it is a data interchange library which means its used to encode and exchange data between programs. It was never meant to be used for configuration and doesn't have a way to read a text-based definition of the data since it deals with binary files.
Looking at your config format you have two options:
The format you've chosen looks a lot like HOCON, so https://github.com/typesafehub/config should be able to read it and provide a readable config object with a small amount of editing.
If you want a type-safe config (defining the structure of the config as an actual java object) you will need to use some other format which supports deserialization to object. A JSON configuration can be read into objects using libraries like https://github.com/google/gson or https://github.com/FasterXML/jackson

Access fields of returned Java Object

I made a simple client call to the XML-RPC WordPress API/Posts using a xml-rpc client and according to their documentation here it returns a struct. How can i access the return values.
Here is a look at my code:
XmlRpcClient client = new XmlRpcClient("http://www.mywebsite.net/xmlrpc.php", false);
String[] fields = new String[4];
fields[0] = "post_id";
fields[1] = "post_title";
fields[2] = "post_date";
fields[3] = "post_content";
Object token = client.invoke("wp.getPost", new Object[]{"0","myusername", "mypassword", 1545, fields });
System.out.println(token);
When I print use
System.out.println(token);
I get the following out put:
{item_one=I am item number one, item_two=I am Item two...}
How can I access item_one and item_two?

There's a bit of information missing (what's the fully qualified name of XmlRpcClient?), but assuming that client.invoke actually returns just an Object and not something more specific that has accessor methods, you can parse the response using something like this:
Object token = client.invoke("wp.getPost", new Object[]{"0","myusername", "mypassword", 1545, fields });
String[] items = token.toString().split(",");
for (String item : items) {
String[] parts = item.split("=");
String key = parts[0];
String value = parts[1];
// do stuff with your keys and values here
}
Of course this isn't perfect code -- you may need to check for nulls, use String.trim(), etc, but it should get you started.

You don't have a true Java representation of the data returned, in that you don't have an object on which you can access
token.item_one
rather you have a string containing a representation of a set - that is something that (in concept) from which you could retrieve an value by its name
token.get("item_one")
This string format is probably JSON, which pretty much looks like JavaScript, and hence can represent quite complex data. In general you can have arrays of objects and objects containing objects (for example, a Customer might contain an Address object)
So you have two possibilities:
1). parse the string into a true Java representation such as one of the standard Java collection classes. You then use the get-by-name style I show above.
2). define a Java class that mimics the structure of the data and then parse the string to fill out such an object, you can then use the "dot" form of access - you really have a Java Object representing the data.
In the first case there are suitable libraries such as quickJson
For the second you can use implementations of standards such as JAX/B, which tends to be more work as you may need to construct the target Java Class by hand. Enterprise Java runtimes will give you these facilities and perhaps tooling to help, or look at implementaitons such as Jackson. You will see that JAX/B hada focus on mapping from XML to Java, but tutorials such as this show how to work with JSON instead.
My guess is that the first option, simple parsing to a collection may be enough for you.