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Kaitai code writing

I recently started kaitai-struct for dealing with arbitrary binary formats. I have created the .ksy file for my data and parsed it to targeted language that is java. Now can anyone point me how to pass the input file that has the data and how to get the data that is parsed as output so that I can write code to manipulate that data to my requirements? Is there any tutorial on how to write code depending on the data we get.
Thanks in advance.

First you have to generate Java classes from the .ksy file using the Kaitai Struct Compiler or the WebIDE. You can find more information how to use the compiler in the Kaitai user guide.
If you use the WebIDE then just simply right-click on your .ksy file and select the Generate parser > Java menu item.
After you have the generated Java code, you can parse a structure directly from a local file like this:
AnExampleClass output = AnExampleClass.fromFile("an_example.data");
// ... manipulate output ...
Or you can parse a structure from a byte array (byte[]):
AnExampleClass output = new AnExampleClass(new KaitaiStream(byteArray));
// ... manipulate output ...
Note that parsing from non-seekable streams (i.e. FileInputStream, BufferedInputStream, etc) is not supported and probably won’t be supported, as a lot of parsing functionality in KS relies on seek support.
You can read the generic documentation how to use the API here and you can find the Java-specific documentation here.

The answer from koczkatamas is outdated.
There are now specific implementations.
The snippet would be
AnExampleClass output = new AnExampleClass(new ByteBufferKaitaiStream(byteArray));
See this issue for more details

Converting stanford parser typed dependencies to RDF format

New to Stackoverflow and new to RDF and typed dependencies. But here is what I got so far: I am currently using the Stanford parser to extract typed dependencies from a sentence in a Java program. I wonder how do I convert these typed dependencies to N-triples RDF format?
Later I will write the RDF to a Sesame repository, but that is another question. So what I am really asking is how do I convert Stanford parser typed dependencies to RDF format? I am writing the code in Java in Eclipse.
The typed dependencies for the sentence "John likes coke" will be:
[nsubj(likes-2, John-1), root(ROOT-0, likes-2), dobj(likes-2, coke-3)]

Converting any data to RDF consists of thinking what the things are that you want to represent, and the coming up with a vocabulary (or ontology) for them. There may actually be an existing vocbulary out there for this thing that you can reuse, but for the purpose of this question, let's assume you'll mint your own vocabulary.
Since every vocabulary term in RDF is a URI, we will need a namespace first. Let's, for now, settle on http://example.org/stanford (prefix sp). We'll need vocabulary terms for making something a dependency, for declaring the specific type of dependency, and for expressing the relations between sentence fragments that make up the dependency. To keep it simple, the specific sentence fragment example you gave could be modeled in RDF as follows:
#prefix sp: <http://example.org/stanford/>
#prefix : <http://example.org/>
:nsubj1 a sp:NominalSubject;
sp:governor :likes-2;
sp:dependent :john-1 .
:s1 a sp:Root ;
sp:dependent :likes-2 .
:dobj1 a sp:DirectObject ;
sp:governor :likes-2;
sp:dependent :coke-3.
etc.
To make this happen in Java/Sesame, you should probably write something that reads input from the Stanford Parser, and converts each dependency on a case by case basis to the equivalent RDF terms (tip: it's probably a good idea to declare some constants for your RDF terms), and then either write directly to disk via Sesame's Rio parser/writer, build up an in-memory Model as you go, or even create a simple Repository (basically a database) where you add your RDF data.
I suggest you give this a try, using some of the existing tutorials/documentation that exist for getting started with programming using Sesame. If you get stuck somewhere, you could write a followup question with your specific problem.

Difference between SolrJ's ResponseParsers

The SolrJ library offers different parsers for Solr's responses.
Namely:
BinaryResponseParser
StreamingBinaryResponseParser
NoOpResponseParser
XMLResponseParser
Sadly the documentation doesn't say much about them, other than:
SolrJ uses a binary format, rather than XML, as its default format.
Users of earlier Solr releases who wish to continue working with XML
must explicitly set the parser to the XMLResponseParser, like so:
server.setParser(new XMLResponseParser());
So it looks like the XMLResponseParser is there mainly for legacy purposes.
What are the differences between the others parsers?
Can I expect performance improvements by using an other parser over the XMLResponseParser?

The Binary Stream Parsers is meant to work directly with the Java Object Format (the binary POJO format) to make the creation of data objects as smooth as possible on the client side.
The XML parser was designed to work with the old response format where there wasn't any real alternatives (as there was no binary response format in Solr). It's a lot more work to consider all the options for an XML format than use the binary format directly.
The StreamingBinaryResponseParser does the same work as the BinaryResponseParser, but has been designed to make streaming documents (i.e. not creating a list of documents and returning that list, but instead return each document by itself without having to hold them all in memory at the same time) possible. See SOLR-2112 for a description of the feature and why it was added.
Lastly, yes, if you're using SolrJ, use the binary response format, unless you have a very good reason for using the XML based one. If you have to ask the question, you're probably better off with the binary format.

How do I convert a Java Hashtable to an NSDictionary (obj-C)?

At the server end (GAE), I've got a java Hashtable.
At the client end (iPhone), I'm trying to create an NSDictionary.
myHashTable.toString() gets me something that looks darned-close-to-but-not-quite-the-same-as [myDictionary description]. If they were the same, I could write the string to a file and do:
NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:tmpFile];
I could write a little parser in obj-C to deal with myHashtable.toString(), but I'm sort-of hoping that there's a shortcut already built into something, somewhere -- I just can't seem to find it.
(So, being a geek, I'll spend far longer searching the web for a shortcut than it would take me to write & debug the parser... ;)
Anyway -- hints?
Thanks!

I would convert the Hashtable into something JSON-like and take it on the iPhone side.
Hashtable.toString() is not ideal, it will have problem with spaces, comma and quotation marks.
For JSON-to-NSDictionary, you can find the json-framework tools under http://www.json.org/

As j-16 SDiZ mentioned, you need to serialize your hashtable. It can be to json, xml or some other format. Once serialized, you need to deserialize them into an NSDictionary. JSON is probably the easiest format to do this with plenty of libraries for both Objective-C and Java. http://json.org has a list of libraries.

Developing a (file) exchange format for java

I want to come up with a binary format for passing data between application instances in a form of POFs (Plain Old Files ;)).
Prerequisites:
should be cross-platform
information to be persisted includes a single POJO & arbitrary byte[]s (files actually, the POJO stores it's names in a String[])
only sequential access is required
should be a way to check data consistency
should be small and fast
should prevent an average user with archiver + notepad from modifying the data
Currently I'm using DeflaterOutputStream + OutputStreamWriter together with InflaterInputStream + InputStreamReader to save/restore objects serialized with XStream, one object per file. Readers/Writers use UTF8.
Now, need to extend this to support the previously described.
My idea of format:
{serialized to XML object}
{delimiter}
{String file name}{delimiter}{byte[] file data}
{delimiter}
{another String file name}{delimiter}{another byte[] file data}
...
{delimiter}
{delimiter}
{MD5 hash for the entire file}
Does this look sane?
What would you use for a delimiter and how would you determine it?
The right way to calculate MD5 in this case?
What would you suggest to read on the subject?
TIA.

It looks INsane.
why invent a new file format?
why try to prevent only stupid users from changing file?
why use a binary format ( hard to compress ) ?
why use a format that cannot be parsed while being received? (receiver has to receive entire file before being able to act on the file. )
XML is already a serialization format that is compressable. So you are serializing a serialized format.

Would serialization of the model (if you are into MVC) not be another way? I'd prefer to use things in the language (or standard libraries) rather then roll my own if possible. The only issue I can see with that is that the file size may be larger than you want.

1) Does this look sane?
It looks fairly sane. However, if you are going to invent your own format rather than just using Java serialization then you should have a good reason. Do you have any good reasons (they do exist in some cases)? One of the standard reasons for using XStream is to make the result human readable, which a binary format immediately loses. Do you have a good reason for a binary format rather than a human readable one? See this question for why human readable is good (and bad).
Wouldn't it be easier just to put everything in a signed jar. There are already standard Java libraries and tools to do this, and you get compression and verification provided.
2) What would you use for a delimiter and how determine it?
Rather than a delimiter I'd explicitly store the length of each block before the block. It's just as easy, and prevents you having to escape the delimiter if it comes up on its own.
3) The right way to calculate MD5 in this case?
There is example code here which looks sensible.
4) What would you suggest to read on the subject?
On the subject of serialization? I'd read about the Java serialization, JSON, and XStream serialization so I understood the pros and cons of each, especially the benefits of human readable files. I'd also look at a classic file format, for example from Microsoft, to understand possible design decisions from back in the days that every byte mattered, and how these have been extended. For example: The WAV file format.

Let's see this should be pretty straightforward.
Prerequisites:
0. should be cross-platform
1. information to be persisted includes a single POJO & arbitrary byte[]s (files actually, the POJO stores it's names in a String[])
2. only sequential access is required
3. should be a way to check data consistency
4. should be small and fast
5. should prevent an average user with archiver + notepad from modifying the data
Well guess what, you pretty much have it already, it's built-in the platform already:Object Serialization
If you need to reduce the amount of data sent in the wire and provide a custom serialization ( for instance you can sent only 1,2,3 for a given object without using the attribute name or nothing similar, and read them in the same sequence, ) you can use this somehow "Hidden feature"
If you really need it in "text plain" you can also encode it, it takes almost the same amount of bytes.
For instance this bean:
import java.io.*;
public class SimpleBean implements Serializable {
private String website = "http://stackoverflow.com";
public String toString() {
return website;
}
}
Could be represented like this:
rO0ABXNyAApTaW1wbGVCZWFuPB4W2ZRCqRICAAFMAAd3ZWJzaXRldAASTGphdmEvbGFuZy9TdHJpbmc7eHB0ABhodHRwOi8vc3RhY2tvdmVyZmxvdy5jb20=
See this answer
Additionally, if you need a sounded protocol you can also check to Protobuf, Google's internal exchange format.

You could use a zip (rar / 7z / tar.gz / ...) library. Many exists, most are well tested and it'll likely save you some time.
Possibly not as much fun though.

I agree in that it doesn't really sound like you need a new format, or a binary one.
If you truly want a binary format, why not consider one of these first:
Binary XML (fast infoset, Bnux)
Hessian
google packet buffers
But besides that, many textual formats should work just fine (or perhaps better) too; easier to debug, extensive tool support, compresses to about same size as binary (binary compresses poorly, and information theory suggests that for same effective information, same compression rate is achieved -- and this has been true in my testing).
So perhaps also consider:
Json works well; binary support via base64 (with, say, http://jackson.codehaus.org/)
XML not too bad either; efficient streaming parsers, some with base64 support (http://woodstox.codehaus.org/, "typed access API" under 'org.codehaus.stax2.typed.TypedXMLStreamReader').
So it kind of sounds like you just want to build something of your own. Nothing wrong with that, as a hobby, but if so you need to consider it as such.
It likely is not a requirement for the system you are building.

Perhaps you could explain how this is better than using an existing file format such as JAR.
Most standard files formats of this type just use CRC as its faster to calculate. MD5 is more appropriate if you want to prevent deliberate modification.

Bencode could be the way to go.
Here's an excellent implementation by Daniel Spiewak.
Unfortunately, bencode spec doesn't support utf8 which is a showstopper for me.
Might come to this later but currently xml seems like a better choice (with blobs serialized as a Map).