could any one help me out to solve this.
Following is a function java
Actually the following function has a character array as a return type
public char[] getTextCharacters(int [] holderForStartAndLength)
{
}
Could any one help me to do the same in ruby
Thank you in advance
--
Posted via http://www.ruby-forum.com/.
Hi,
public char getTextCharacters(int holderForStartAndLength)
{
}Could any one help me to do the same in ruby
Oh sure!
def getTextCharacters(holder_for_start_and_length)
end
> Actually the following function has a character array as a return type
It doesn't matter. Ruby is a dynamic language. Please check out these slides:
http://onestepback.org/articles/10things/
Cheers,
Peter
Actually the following function has a character array as a return type
public char getTextCharacters(int holderForStartAndLength)
{
}
Having done far too much of this recently, my guess is it'll look something like:
def get_text_characters
result =# get the characters and start from whatever...
return result, start
end
I ignored the holderForStartAndLength because the name hints that they are a stupid java hack for not having rich return values. In get_text_characters we don't bother with length because our array (or string... depends on how you actually want to use it) knows it's length and we return the start offset with it. You'd call it like:
On Nov 21, 2007, at 02:00 , Martin Durai wrote:
chars, offset = get_text_characters
Hi,
> public char getTextCharacters(int holderForStartAndLength)
> {
> }
This won't even compile because there is no "return" statement. Also,
using an array to pass two values is at best sub optimal. And since
you do not provide any details about the class at hand nobody can
really help you.
> Could any one help me to do the same in ruby
Oh sure!
def getTextCharacters(holder_for_start_and_length)
end
LOL
Actually, we can make this even *more* rubyish:
def get_text_characters holder_for_start_and_length
end
Cheers
robert
2007/11/21, Peter Szinek <peter@rubyrailways.com>:
--
use.inject do |as, often| as.you_can - without end
I do not like this ---------------------------------^
def get_text_chars start=0, length=1
IOW you cannot port Java to Ruby, it will remain Java in disguise.
Robert
On Nov 21, 2007 11:23 AM, Ryan Davis <ryand-ruby@zenspider.com> wrote:
On Nov 21, 2007, at 02:00 , Martin Durai wrote:
> Actually the following function has a character array as a return type
>
> public char getTextCharacters(int holderForStartAndLength)
--
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/
Robert Klemme wrote:
2007/11/21, Peter Szinek <peter@rubyrailways.com>:
Hi,
public char getTextCharacters(int holderForStartAndLength)
{
}This won't even compile because there is no "return" statement. Also,
using an array to pass two values is at best sub optimal. And since
you do not provide any details about the class at hand nobody can
really help you.Could any one help me to do the same in ruby
Oh sure!
def getTextCharacters(holder_for_start_and_length)
endLOL
Actually, we can make this even *more* rubyish:
>
> def get_text_characters holder_for_start_and_length
> end
Ah, thanks Robert The most trivial tasks are the easiest to screw up, right?
Hi peter,
i have attached my java code which i have to port to ruby. could you
help me with this
public char getTextCharacters(int holderForStartAndLength)
{
if( eventType == TEXT ) {
if(usePC) {
holderForStartAndLength[0] = pcStart;
holderForStartAndLength[1] = pcEnd - pcStart;
return pc;
} else {
holderForStartAndLength[0] = posStart;
holderForStartAndLength[1] = posEnd - posStart;
return buf;
}
} else if( eventType == START_TAG
>> eventType == END_TAG
>> eventType == CDSECT
>> eventType == COMMENT
>> eventType == ENTITY_REF
>> eventType == PROCESSING_INSTRUCTION
>> eventType == IGNORABLE_WHITESPACE
>> eventType == DOCDECL)
{
holderForStartAndLength[0] = posStart;
holderForStartAndLength[1] = posEnd - posStart;
return buf;
} else if(eventType == START_DOCUMENT
>> eventType == END_DOCUMENT) {
//throw new XmlPullParserException("no content available to
read");
holderForStartAndLength[0] = holderForStartAndLength[1] =
-1;
return null;
} else {
throw new IllegalArgumentException("unknown text eventType:
"+eventType);
}
// String s = getText();
// char cb = null;
// if(s!= null) {
// cb = s.toCharArray();
// holderForStartAndLength[0] = 0;
// holderForStartAndLength[1] = s.length();
// } else {
// }
// return cb;
}
All these code comes unde java version of pull parser
Robert Klemme wrote:
2007/11/21, Peter Szinek <peter@rubyrailways.com>:
Hi,
> public char getTextCharacters(int holderForStartAndLength)
> {
> }This won't even compile because there is no "return" statement. Also,
using an array to pass two values is at best sub optimal. And since
you do not provide any details about the class at hand nobody can
really help you.> Could any one help me to do the same in ruby
Oh sure!
def getTextCharacters(holder_for_start_and_length)
endLOL
Actually, we can make this even *more* rubyish:
def get_text_characters holder_for_start_and_length
end
Cheers
robert
--
Posted via http://www.ruby-forum.com/\.
Robert Klemme wrote:
Actually, we can make this even *more* rubyish:
def get_text_characters holder_for_start_and_length
end
Is it actually more rubyish to omit the parenthesis? I often find it much harder to read, specially in e-mails with a variable-spaced font.
Best regards,
Jari Williamsson
nonsense... you can port it just fine if you allow for design changes. that is why I didn't pass in start or length at all... they're RETURN values, not arguments.
On Nov 21, 2007, at 02:41 , Robert Dober wrote:
public char getTextCharacters(int holderForStartAndLength)
I do not like this ---------------------------------^
def get_text_chars start=0, length=1
IOW you cannot port Java to Ruby, it will remain Java in disguise.
First of all I would create a class for the return values, like
TextSubRange = Struct.new :text, :start, :end
Then I would change all the if (x==..||x==...) to use a case statement.
Btw, I would do the same to the Java code (i.e. create another class
and use "switch").
Cheers
robert
2007/11/21, Martin Durai <martin@angleritech.com>:
Hi peter,
i have attached my java code which i have to port to ruby. could you
help me with thispublic char getTextCharacters(int holderForStartAndLength)
{
if( eventType == TEXT ) {
if(usePC) {
holderForStartAndLength[0] = pcStart;
holderForStartAndLength[1] = pcEnd - pcStart;
return pc;
} else {
holderForStartAndLength[0] = posStart;
holderForStartAndLength[1] = posEnd - posStart;
return buf;}
} else if( eventType == START_TAG
>> eventType == END_TAG
>> eventType == CDSECT
>> eventType == COMMENT
>> eventType == ENTITY_REF
>> eventType == PROCESSING_INSTRUCTION
>> eventType == IGNORABLE_WHITESPACE
>> eventType == DOCDECL)
{
holderForStartAndLength[0] = posStart;
holderForStartAndLength[1] = posEnd - posStart;
return buf;
} else if(eventType == START_DOCUMENT
>> eventType == END_DOCUMENT) {
//throw new XmlPullParserException("no content available to
read");
holderForStartAndLength[0] = holderForStartAndLength[1] =
-1;
return null;
} else {
throw new IllegalArgumentException("unknown text eventType:
"+eventType);
}
// String s = getText();
// char cb = null;
// if(s!= null) {
// cb = s.toCharArray();
// holderForStartAndLength[0] = 0;
// holderForStartAndLength[1] = s.length();
// } else {
// }
// return cb;
}All these code comes unde java version of pull parser
--
use.inject do |as, often| as.you_can - without end
The simplest conversion is this:
def getTextCharacters(holholderForStartAndLength)
case @eventType
when TEXT
if @usePC
holderForStartAndLength[0] = @pcStart
holderForStartAndLength[1] = @pcEnd - @pcStart
return @pc
else
holderForStartAndLength[0] = @posStart
holderForStartAndLength[1] = @posEnd - @posStart
return @buf
end
when START_TAG, END_TAG, CDSECT, COMMENT, ENTITY_REF, PROCESSING_INSTRUCTION, IGNORABLE_WHITESPACE, DOCDECL
holderForStartAndLength[0] = @posStart
holderForStartAndLength[1] = @posEnd - @posStart
return @buf
when START_DOCUMENT, END_DOCUMENT
holderForStartAndLength[0] = holderForStartAndLength[1] = -1
return nil
else
raise "unknown text eventType: " + @eventType
end
end
Of course this is untested and assumes that the class that defines it will also set up the various class variables (the @something in the code) and the constants (the SOMETHING in the code). You should also consider creating your own exception class for the raise.
Please also read "Pounding A Nail: Old Shoe or Glass Bottle?" by Alex Papadimoulis at http://weblogs.asp.net/alex_papadimoulis/archive/2005/05/25/408925.aspx
Why the hell are you not using an existing ruby xml library, you know that your's will be the slowest xml parser on earth?
This endeavour is made of fail.
<code snipped>
I would refactor that code before you consider porting it to anything. Theres
a lot of external dependencies and a lot of unsafe constructs. That single
function uses the following instance members:
usePC
eventType
pcStart
pcEnd
posStart
posEnd
pc
buf
getText
You are also not doing a lot of input value checking, and the function is very
non-DRY. All of the return values are side effects of the method,
defined elsewhere.
The position holder (the function argument) should be a class.
However its par for the course in Java really. However even in Java you would
find that function very difficult to unit test without complex mocking.
You would never write a Ruby function that behaved like that. You would break
up the responsibilities of the function into individual pieces
(functions), then take advantage
of Ruby's better literal syntax and conditionals to clear up the messy
conditionals.
(The Ruby switch statement is a thing of beauty).
On Nov 21, 2007 10:25 AM, Martin Durai <martin@angleritech.com> wrote:
Hi peter,
i have attached my java code which i have to port to ruby. could you
help me with this
I left that to optimize for someone else. 
Seriously: most of the time I use brackets in method definitions - not
necessary usages.
Kind regards
robert
2007/11/21, Jari Williamsson <jari.williamsson@mailbox.swipnet.se>:
Robert Klemme wrote:
> Actually, we can make this even *more* rubyish:
>
> def get_text_characters holder_for_start_and_length
> endIs it actually more rubyish to omit the parenthesis? I often find it
much harder to read, specially in e-mails with a variable-spaced font.
--
use.inject do |as, often| as.you_can - without end
Robert Klemme wrote:
> Actually, we can make this even *more* rubyish:
>
> def get_text_characters holder_for_start_and_length
> endIs it actually more rubyish to omit the parenthesis? I often find it
much harder to read, specially in e-mails with a variable-spaced font.
ok that is not the case normally however,
Nevertheless most people still think it is terrible (e.g. David
Black), I believe - and some others, Ara IIRC - believe it is much
easier to read.
Consider this, your brain has not yet used to missing parens, and it
is actually looking for them, that already is some unnecessary work,
right ;).
I really would love to know if Smalltalkers feel the same when they
see Ruby using minium parens style, Rick?
I guess I would use parens if I were paid to write Ruby and somebody
paying askes me nicely (like "or you will get fired").
So somebody ready to pay???
Cheers
Robert
On Nov 21, 2007 2:44 PM, Jari Williamsson <jari.williamsson@mailbox.swipnet.se> wrote:
Best regards,
Jari Williamsson
--
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/
>>> public char getTextCharacters(int holderForStartAndLength)
> I do not like this ---------------------------------^
>
> def get_text_chars start=0, length=1
>
> IOW you cannot port Java to Ruby, it will remain Java in disguise.nonsense... you can port it just fine if you allow for design changes.
that is why I didn't pass in start or length at all... they're RETURN
values, not arguments.
Ryan we are not going to write Java code in Ruby only because it can
be done, are we?
Probably I was not clear, of course you can Java code in a way that
the Ruby interpreter produces the same results, but does this make it
Ruby code?
R.
On Nov 21, 2007 9:32 PM, Ryan Davis <ryand-ruby@zenspider.com> wrote:
On Nov 21, 2007, at 02:41 , Robert Dober wrote:
--
what do I think about Ruby?
http://ruby-smalltalk.blogspot.com/
Thank you robert,
my task is to port java classes and methods to ruby just like tha above
one.
could you help me with this porting
Then I would change all the if (x==..||x==...) to use a case statement.
Btw, I would do the same to the Java code (i.e. create another class
and use "switch").Cheers
robert
--
Posted via http://www.ruby-forum.com/\.
Peter Hickman wrote:
The simplest conversion is this:
> [...]
holderForStartAndLength[0] = @pcStart
holderForStartAndLength[1] = @pcEnd - @pcStart
I would probably write something like:
holder_for_start_and_length = [@pcStart, @pcEnd - @pcStart]
Best regards,
Jari Williamsson
No, but I can ask you nicely.
Seriously: it just occurs to me that the topic of using or not using parens seems to come up much less frequently than the topic of whether to use curly braces or "do end" with blocks. Maybe that's an indication that people faster adjust to the missing parens, dunno.
Kind regards
robert
On 21.11.2007 17:13, Robert Dober wrote:
On Nov 21, 2007 2:44 PM, Jari Williamsson > <jari.williamsson@mailbox.swipnet.se> wrote:
Robert Klemme wrote:
Actually, we can make this even *more* rubyish:
def get_text_characters holder_for_start_and_length
endIs it actually more rubyish to omit the parenthesis? I often find it
much harder to read, specially in e-mails with a variable-spaced font.ok that is not the case normally however,
Nevertheless most people still think it is terrible (e.g. David
Black), I believe - and some others, Ara IIRC - believe it is much
easier to read.Consider this, your brain has not yet used to missing parens, and it
is actually looking for them, that already is some unnecessary work,
right ;).
I really would love to know if Smalltalkers feel the same when they
see Ruby using minium parens style, Rick?I guess I would use parens if I were paid to write Ruby and somebody
paying askes me nicely (like "or you will get fired").
So somebody ready to pay???
IMO, Ryan's example was farthest from writing Java in Ruby of all the
examples given in this thread.
-mental
On Thu, 22 Nov 2007 06:50:07 +0900, "Robert Dober" <robert.dober@gmail.com> wrote:
> IOW you cannot port Java to Ruby, it will remain Java in disguise.
nonsense... you can port it just fine if you allow for design changes.
that is why I didn't pass in start or length at all... they're RETURN
values, not arguments.
Ryan we are not going to write Java code in Ruby only because it can
be done, are we?
Robert Dober wrote:
Consider this, your brain has not yet used to missing parens, and it
is actually looking for them, that already is some unnecessary work,
right ;).
I would say my brain is scanning for some kind of separator, and the space is too similar to the Rubish underscores, which (sometimes) makes it harder than necessary IMO.
With good syntax highlighting, though, this is a non-issue.
Best regards,
Jari Williamsson