I am trying to port code written in Java to Objective C (for iPhone), but I'm kind of confused about a few lines of my code (mentioned below). How should I port this efficiently?
Namespace nmgrhistory=Namespace.getNamespace("history", "http://www.mywebsite.com/History.xsd");
pEventEl.addContent(new Element("History",nmgrhistory));
Namespace nmgrState=Namespace.getNamespace("state", "http://www.mywebsite.com/State.xsd");
pEventEl.addContent(new Element("State",nmgrState));
Iterator<Element> eld=(Iterator<Element>) pEventEl.getChild(
pEventEl.getName() == "event"? "./history:history/state:state" : "./state:state",pEventEl.getNamespace());
I'm not very sure about the replacements for the classes Namespace, Iterator and Element.
Anybody having idea or having done this before, please enlighten me.
Ok... So although these are not the actual replacements ... But basically what u need for parsing XML in Objecive - C is "NSXMLParser"
so u can say that NSXMLParser is the replacement for Namespace
And for "Iterator" NSXMLParserDelegate has a method named:-
– parser:didStartElement:namespaceURI:qualifiedName:attributes:
OR
– parser:foundCharacters:
I don't know java, but the url's your are pointing at are .xsd files which are xml definition files. XML parsing on iOS is somewhat limited out of the box: NSXMLParser.
I strongly recommend one of the bazillion open source XML parsers. They're much more user friendly.
Well thanks to all for making the efforts to answer, but I got a nice library TouchXML that solves the purpose.
Related
I'm trying to 1) compute the digital signature for an XML string, 2) unmarshall the XML string to a Java object, 3) marshall the object back to an XML string, and 4) re-compute signature, and verify against the signature from step 1.
Problem is that the namespace prefixes usually get changed during the round trip (steps 2-3), so I need a way to standardize them before and after the round trip. Otherwise, the digital signatures (steps 1 and 4) obviously won't match.
I figured I need something like PrefixRewrite="sequential" in section 2.5.4 of https://www.w3.org/TR/xml-c14n2/Overview_diff.html#sec-Example-PrefixRewriteSeq. I found a Python library that supposedly does that (https://github.com/dept2/c14n2py), but I can't seem to find a Java library with that option (org.apache.xml.security.c14n.Canonicalizer doesn't have it). I've also been able to hard-code the namespace prefixes in my marshaller, but that's not an acceptable solution for me.
Can anybody recommend a Java library for XML canonicalization with the PrefixRewrite="sequential" option?
Thanks!!
That python library c14n2py was written from sources of Java library, that lies nearby: https://github.com/dept2/c14n2
You could try to use it
I don't know java and can't get JavaCall.jl to work with java.text.DecimalFormat. In MATLAB this is very simple -- just check out this link.
Reading the JavaCall.jl documentation, I tried replicating the provided example with DecimalFormat and got this far:
julia>using JavaCall
julia>JavaCall.init(["-Xmx128M"])
julia>jdf = #jimport java.text.DecimalFormat
After that, I got a bunch of errors. (bear in mind: I absolutely have no clue as to how Java works?)
Please help!
It's not clear from the question whether you're looking to know more about JavaCall.jl or just to use some comma separated formatting.
If the latter, then you can use the Formatting.jl package: https://github.com/JuliaIO/Formatting.jl
julia> using Formatting
julia> sprintf1("%'.02f", 123456789)
"123,456,789.00"
And then you don't need any Java.
This package also has a bunch of other formatting options.
I was searching for free translation dictionaries. Freedict (freedict.org) provides the ones I need but I don't know, how to parse the *.index and *.dict files. I also don't really know, what to google, to find useful information about these formats.
The *.index files look following:
00databasealphabet QdGI l
00databasedictfmt1121 B b
00databaseinfo c 5o
00databaseshort 6E u
00databaseurl 6y c
00databaseutf8 A B
a BHO M
a bad risc BHa u
a bag of nerves BII 2
[...]
and the *.dict files:
[Lot of info stuff]
German-English FreeDict Dictionary ver. 0.3.4
Pipi machen /piːpiːmaxən/
to pee; to piss
(Aktien) zusammenlegen /aktsiːəntsuːzamənleːgən/
to merge (with)
[...]
I would be glad to see some example projects (preferably in python, but java, c, c++ are also ok) to understand how to handle these files.
It is too late. However, i hope that it can be useful for others like me.
JGoerzen writes a Dictdlib lib. You can see more details how he parse .index and .dict files.
https://github.com/jgoerzen/dictdlib/blob/master/dictdlib.py
dictd considers its format of .index and .dict[.dz] as private, to reserve itself the right to change it in the future.
If you want to process it directly anyway, the index contains the headwords and the .dict[.dz] contains definitions. It is optionally compressed with a special modified gzip algorithm providing almost random access, which gzip normally does not. The index contains 3 columns per line, tab separated:
The headword for looking up the definition.
The absolute byte position of the definition in the .dict[.dz] file, base64 encoded.
The length of the definition in bytes, base64 encoded.
For more details see the dict(8) man page (section Database Format) you should have found in your research before asking your question. For processing the headwords correctly, you'd have to consider encoding and character collation.
Eventually it would be better to use an existing library to read dictd databases. But that really depends on whether the library is good (no experience here).
Finally, as you noted yourself, XML is made exactly for easy processing. You could extract the headwords and translations using XPath, leaving out all the grammatical stuff and no need to bother parsing anything.
After getting this far the next problem would be that there is no one-to-one mapping between words in different lanuages...
struct is necessary when you try to parse some file format like ELF, etc...
Is there something like C's struct in Java?
Or can Java be used to parse ELF/binary format directly in the first place?
If you need a struct for grouping different data of the same type, Java has a class, and a class is better in logically grouping data than a struct because it includes operations on the data as well.
If you want to format ELF, then you may have to look at the "The ELF Parser" section in http://www.icsa.inf.ed.ac.uk/research/groups/hase/manuals/design/javahase.html. See also LibElf and GElf - A Library to Manipulate ELf Files (an old article)
Unfortunatly there is no decent support to read binary structured data in java.
This example reads image header into a byte array and assembles the required information.
There's ByteBuffer.
Edit
This is just to answer how you might parse the ELF format, which seemed to be what the OP was actually asking for.
For example (I assume this is the same format, apologies if it's a completely different ELF format, either way, it shows the same process):
http://jumdbrowser.googlecode.com/svn-history/r3/trunk/UmdBrowser/src/jpcsp/format/Elf32.java
Edit: answer to the first question
Java classes
How would I parse this JSON array in Java? I'm confused because there is no object. Thanks!
EDIT: I'm an idiot! I should have read the documentation... that's probably what it's there for...
[
{
"id":"63565",
"name":"Buca di Beppo",
"user":null,
"phone":"(408)377-7722",
"address":"1875 S Bascom Ave Campbell, California, United States",
"gps_lat":"37.28967000",
"gps_long":"-121.93179700",
"monhh":"",
"tuehh":"",
"wedhh":"",
"thuhh":"",
"frihh":"",
"sathh":"",
"sunhh":"",
"monhrs":"",
"tuehrs":"",
"wedhrs":"",
"thuhrs":"",
"frihrs":"",
"sathrs":"",
"sunhrs":"",
"monspecials":"",
"tuespecials":"",
"wedspecials":"",
"thuspecials":"",
"frispecials":"",
"satspecials":"",
"sunspecials":"",
"description":"",
"source":"ripper",
"worldsbarsname":"BucadiBeppo31",
"url":"www.bucadebeppo.com",
"maybeDupe":"no",
"coupontext":"",
"couponimage":"0",
"distance":"1.00317",
"images":[
0
]
}
]
It is perfectly valid JSON. It is an array containing one object.
In JSON, arrays and objects don't have names. Only attributes of objects have names.
This is all described clearly by the JSON syntax diagrams at http://json.org. (FWIW, the site has translations in a number of languages ...)
How do you parse it? There are many libraries for parsing JSON. Many of them are linked from the site above. I suggest you use one of those rather than writing your own parsing code.
In response to this comment:
OTOH, writing your own parser is a reasonable project, and a good exercise for both learning JSON and learning Java (or whatever language). A reasonable parser can be written in about 500 lines of text.
In my opinion (having written MANY parsers in my time), writing a parser for a language is a very inefficient way to gain a working understanding the syntax of a language. And depending on how you implement the parser (and the nature of the language syntax specification) you can easily get an incorrect understanding.
A better approach is to read the language's syntax specification, which the OP has now done, and which you would have to do in order to implement a parser.
Writing a parser can be a good learning exercising, but it is really a learning exercise in writing parsers. Even then, you need to pick an appropriate implementation approach, and an appropriate language to be parsed.
It's an array containing one element. That element is an object. The object (dictionary) contains about 20 name/value pairs.