DZone Snippets: object code

You have a nil object when you didn't expect it!

freezzo (Randy) — Fri, 07 Dec 2007 16:14:11 GMT

As seen on my webpage: http://freezzo.com



<%= @object.association.variable rescue nil %>

Excel object

sarunbe (Arun Kumar) — Wed, 18 Jul 2007 14:14:08 GMT

// Excel object



// 'create object

Set excelobj = CreateObject( "Excel.Application")

Set exp_data_workbook=excelobj.workbooks.open("c:\debug_expected.xls")





'get the sheet count

exp_sheetcnt=exp_data_workbook.Sheets.Count

	



'select a sheet

For i = 1 to exp_sheetcnt

	sheet_tblname=exp_data_workbook.Sheets(i).Name

	If  UCASE(Trim(sheet_tblname)) = "Sheet_name" Then

		exp_data_workbook.Sheets(i).select



		'once selected set the range object	

		set exp_rangeobj=exp_data_workbook.Sheets(i).UsedRange

	end if

next





'Get the column count for the 



columncnt=exp_rangeobj.columns.count



'find  the column index of  the column column_name

		For i=1 to columncnt

			colname=exp_rangeobj.cells(1,i).value

			If UCASE(Trim(colname)) = "column_name" Then

				pos_id_idx = i

				Exit For

			End If

		Next		



'proceess the value from that column



rowcnt=exp_rangeobj.rows.count



		'Strat reading the values from the 2nd row since the first row contains the column names.

		If rowcnt > 1 Then

			For i=2 to rowcnt				 

				'process the expected file row if it has a value

				If  Len(Trim(exp_rangeobj.cells(i,1).value))>0 Then 

					posIndex = (exp_rangeobj.cells(i,pos_id_idx).value) -1

				end if

			next 

		end if

Wrap all methods of an object

haberman (Joshua Haberman) — Thu, 31 May 2007 23:23:12 GMT

Given an existing object "obj", wraps all of its methods. In this case, the wrapper prints a log of the method invocation, and the call stack of the call, but you can modify it to do anything...



virtual_class = class <

virtual_class.class_eval {

  obj.methods.each { |method|

    the_alias = method.gsub(/([^?]+)(\??)/, "\\1_orig\\2").to_sym

    alias_method the_alias, method



    define_method(method) { |*args|

        args_str = args.map { |a| a.inspect }.join(", ")

        unless method == "to_s"

          puts "#{self.inspect_orig}.#{method}(#{args_str}) called from #{caller.inspect}"

        end

        self.send_orig(the_alias, *args)

    }

  }

}

Object alternative to iframe for XHTML 1.0 strict

nathancarnes (Nathan Carnes) — Mon, 23 Apr 2007 23:46:06 GMT

Javascript Ajax Object

pcx99 (Patrick) — Fri, 09 Mar 2007 03:06:18 GMT



// Just a stub function we'll tell ajaxObject to call when it's done

// callback functions get responseText, and responseStat respectively

// in their arguments.

function fin(responseTxt,responseStat) {

  alert(responseStat+' - '+responseTxt);

}



// create a new ajaxObject, give it a url it will be calling and

// tell it to call the function "fin" when its got data back from the server.

var test1 = new ajaxObject('http://someurl.com/server.cgi',fin);

    test1.update();

		

// create a new ajaxObject, give it a url and tell it to call fin when it

// gets data back from the server.  When we initiate the ajax call we'll

// be passing 'id=user4379' to the server.		

var test2 = new ajaxObject('http://someurl.com/program.php',fin);

    test2.update('id=user4379');

		

// create a new ajaxObject but we'll overwrite the callback function inside

// the object to more tightly bind the object with the response hanlder.

var test3 = new ajaxObject('http://someurl.com/prog.py', fin);

    test3.callback = function (responseTxt, responseStat) {

      // we'll do something to process the data here.

      document.getElementById('someDiv').innerHTML=responseTxt;

    }

    test3.update('coolData=47&userId=user49&log=true');	

		

// create a new ajaxObject and pass the data to the server (in update) as

// a POST method instead of a GET method.

var test4 = new ajaxObject('http://someurl.com/postit.cgi', fin);

    test4.update('coolData=47&userId=user49&log=true','POST');



function ajaxObject(url, callbackFunction) {

  var that=this;      

  this.updating = false;

  this.abort = function() {

    if (that.updating) {

      that.updating=false;

      that.AJAX.abort();

      that.AJAX=null;

    }

  }

  this.update = function(passData,postMethod) { 

    if (that.updating) { return false; }

    that.AJAX = null;                          

    if (window.XMLHttpRequest) {              

      that.AJAX=new XMLHttpRequest();              

    } else {                                  

      that.AJAX=new ActiveXObject("Microsoft.XMLHTTP");

    }                                             

    if (that.AJAX==null) {                             

      return false;                               

    } else {

      that.AJAX.onreadystatechange = function() {  

        if (that.AJAX.readyState==4) {             

          that.updating=false;                

          that.callback(that.AJAX.responseText,that.AJAX.status,that.AJAX.responseXML);        

          that.AJAX=null;                                         

        }                                                      

      }                                                        

      that.updating = new Date();                              

      if (/post/i.test(postMethod)) {

        var uri=urlCall+'?'+that.updating.getTime();

        that.AJAX.open("POST", uri, true);

        that.AJAX.setRequestHeader("Content-type", "application/x-www-form-urlencoded");

        that.AJAX.send(passData);

      } else {

        var uri=urlCall+'?'+passData+'×tamp='+(that.updating.getTime()); 

        that.AJAX.open("GET", uri, true);                             

        that.AJAX.send(null);                                         

      }              

      return true;                                             

    }                                                                           

  }

  var urlCall = url;        

  this.callback = callbackFunction || function () { };

}

Prototype-based Ruby

ntk () — Sat, 27 Jan 2007 20:02:18 GMT





# From: http://programming.reddit.com/info/ob4m/comments/cobr4

# Author: Brian Mitchell

# cf. http://t-a-w.blogspot.com/2006/10/prototype-based-ruby.html



Proto = Class.new(Class)    # Beware: magic.

def Proto.clone

  Class.new(self)

end



# Demo

a = Proto.clone

def a.f

  puts 42

end

a.f                     #=> 42



b = a.clone

b.f                     #=> 42

def b.f

  puts 43

end

a.f                      #=> 42

b.f                      #=> 43



def a.g

  "Hello differential inheritance"

end



bool_val = (a.g == b.g)

p bool_val                #=> true







# From: http://www.ruby-forum.com/topic/94696

# cf. http://tech.rufy.com/2006/06/classes-are-just-prototype-pattern.html



AnimalSounds = Module.new



AnimalSounds.class_eval %q!

def createSound(attr_name)

class_eval <<-EOS

   #def self.#{attr_name};  puts "class method '#{attr_name}' called"; end 

   def self.#{attr_name}(arg = nil) 

      str = "class method '#{attr_name}' of class #{self.inspect} called"

      arg ? (puts str + " with " + arg.to_s) : (puts str)

   end

EOS

end!





puts

p AnimalSounds

p AnimalSounds.class

p AnimalSounds.class.superclass

p AnimalSounds.class.ancestors

p AnimalSounds.singleton_methods

puts





Pet = Object.clone.extend(AnimalSounds)    

Pet.createSound("meow")                    # create a class method

Pet.meow                                   

Pet.meow("argument")      



p Pet

p Pet.class

p Pet.class.superclass

p Pet.class.ancestors

p Pet.singleton_methods

puts





fido = Pet.clone           

fido.meow           

fido.meow("argument")

fido.createSound("woof")    

fido.woof

fido.woof("argument")

puts





fido2 = fido.clone                        

fido2.woof

fido2.woof("argument")

fido2.createSound("woof2")                 

fido2.woof2

fido2.woof2("argument")



puts

p Pet.singleton_methods

p fido.singleton_methods

p fido2.singleton_methods

puts

SINGLE-LINE-MOLD

gregg.irwin (Gregg Irwin) — Thu, 16 Nov 2006 05:09:18 GMT



	single-line-mold: func [

	    "Reformats a block or object-spec to a single line."

	    val [any-block! object!]

	] [

	    val: copy either any-block? val [val] [third val]

	    replace/all mold new-line/all val  off  "^/" "^^/"

	]

longest-field-name - Return the longest word in the object, as a string

gregg.irwin (Gregg Irwin) — Mon, 02 Oct 2006 23:04:58 GMT



longest-field-name: func [

    "Return the longest word in the object, as a string."

    obj [object!]

][

    last sort-by-length change-all remove first obj :form

]

words-like - Returns a block of words in the object that match the given pattern.

gregg.irwin (Gregg Irwin) — Sun, 01 Oct 2006 22:25:23 GMT



words-like: func [

    "Returns a block of words in the object that match the given pattern."

    object  [object!]

    pattern [word! any-string!]

    ;??? Add an /unbound refinement

][

    pattern: join form pattern "*"

    collect w [

        foreach word next first object [

            if find/match/any form word pattern [w: bind word in object 'self]

        ]

    ]

]

save Data with db4o

ovhaag (Oliver Haag) — Sun, 17 Sep 2006 19:22:50 GMT

// save Data with db4o



import com.db4o.Db4o;

import com.db4o.ObjectContainer;

import com.db4o.ObjectSet;

import com.db4o.query.Query;

...



public class DbUtil {



  /**

  * save someObject to DB

  */

  public static void saveData(SomeClass someObject, String DbFilename) {

    ObjectContainer db=Db4o.openFile(DbFilename);

    try {

      db.set(idGenerator);

    }

    finally {

      db.close();

    }

  } //saveData(SomeClass ..)



  ..



} //DbUtil