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  • Problem with Java FX Look and Feel

    - by drachenfels
    Hi, I was looking at some of the examples from the Deitel and Deitel's book for Programming in Java, and one of the first examples is a very simple Swing display. Hence this snippet of code : import javax.swing.*; public class cdea { public static void main(String args[]){ JOptionPane.showMessageDialog(null,"\"Welcome to Java Programming!\""); System.exit(0); //end method main } } I read some stuff regarding how one can get native UI look and feel by using UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName()); to the program. However, when I just add this to my main method, it gives me a host of errors. Specifically : Multiple markers at this line - Unhandled exception type IllegalAccessException - Unhandled exception type InstantiationException - Unhandled exception type ClassNotFoundException - Unhandled exception type UnsupportedLookAndFeelException However when I use it as part of a try/catch exception loop (is that what it is called?) as detailed on http://stackoverflow.com/questions/1590863/getting-java-applications-to-look-native-on-windows-how , I get the program running properly. Could anyone tell me in simple language why this is so? As in, why can't I directly get the System look and feel; why do I have to use it with exception handling? I'm new to Java, and OOP in general, so I'm sorry if I'm being too simplistic.

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  • php connection using HttpWebRequest and Get method

    - by Ahmet vardar
    Hi, i have a script returns some string, http://mysite.com/script.php php script; $data = $_GET['q']; $query = "SELECT * FROM `table` WHERE ID = '$data'"; $result = mysql_query($query); $num = mysql_num_rows($result); print $num; i want to connect this script with VB, using this code Dim con As String con = "http://mysite.com/script.php?q=" & My.Settings.setq Dim request = HttpWebRequest.Create(con) request.Method = "GET" Dim response = request.GetResponse() Using reader = New StreamReader(response.GetResponseStream()) msgbox(reader.ReadToEnd()) End Using it is not working. how can i do that ? thanks

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  • django accessing class variables in a view

    - by dana
    hello, i want to make a notification function, and i need fields from 2 different models. how can i access those fields? in my notification view i wrote this data = Notices.objects.filter(last_login<date_follow) where last_login belongs to the model class User , and date_follow to Follow but it is not a proper and correct way of accessing those variables. How can i access them? I need to compare the two dates for realising the notifications that one did not see since his last login. Thanks!

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  • Java: how to initialize String[]?

    - by Heoa
    Error % javac StringTest.java StringTest.java:4: variable errorSoon might not have been initialized errorSoon[0] = "Error, why?"; Code public class StringTest { public static void main(String[] args) { String[] errorSoon; errorSoon[0] = "Error, why?"; } }

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  • jQuery: Freezing/Disabling all events temporarily?

    - by Legend
    I have the following usecase: A div with some buttons When the user clicks on a button, a popup is shown and the background div is faded out to 0.5 opacity The problem is that when the popup comes in, the user is still able to click on the background buttons. At this point, I can remove the entire DIV temporarily but I don't want to do that. Is there anyway I can disable all the previously attached events and then add event handlers ONLY to the current popup? (I mean something like a close button should still work on a popup) Any suggestions?

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  • Applying a function that may fail to all values in a list

    - by Egwor
    I want to apply a function f to a list of values, however function f might randomly fail (it is in effect making a call out to a service in the cloud). I thought I'd want to use something like map, but I want to apply the function to all elements in the list and afterwards, I want to know which ones failed and which were successful. Currently I am wrapping the response objects of the function f with an error pair which I could then effectively unzip afterwards i.e. something like g : (a->b) -> a -> [ b, errorBoolean] f : a-> b and then to run the code ... map g (xs) Is there a better way to do this? The other alternative approach was to iterate over the values in the array and then return a pair of arrays, one which listed the successful values and one which listed the failures. To me, this seems to be something that ought to be fairly common. Alternatively I could return some special value. What's the best practice in dealing with this??

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  • Putting a variable name = value format in Ruby

    - by Calm Storm
    Hi, I would like to add some debugs for my simple ruby functions and I wrote a function as below, def debug(&block) varname = block.call.to_s puts "#{varname} = #{eval(varname,block)}" end debug {:x} #prints x = 5 debug {:y} #prints y = 5 I understand that eval is evil. So I have two questions. Is there any way to write that debug method without using eval? If NO is there a preferred way to do this? Is there any way to pass a list of arguments to this method? I would ideally prefer debug {:x, :y. :anynumOfvariables}. I could not quite figure out how to factor that into the debug method (i.e, to take a list of arguments)

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  • Hash Tables - Java

    - by Antony
    Am about to do a homework, and i need to store quite a lot of information (Dictionary) in a data structure of my choice. I heard people in my classroom saying hash-tables are the way to go. How come?

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  • Replacing emty csv column values with a zero

    - by homerjay
    Hey, So I'm dealing with a csv file that has missing values. What I want my script to is: #!/usr/bin/python import csv import sys #1. Place each record of a file in a list. #2. Iterate thru each element of the list and get its length. #3. If the length is less than one replace with value x. reader = csv.reader(open(sys.argv[1], "rb")) for row in reader: for x in row[:]: if len(x)< 1: x = 0 print x print row Here is an example of data, I trying it on, ideally it should work on any column lenghth Before: actnum,col2,col4 xxxxx , , xxxxx , 845 , xxxxx , ,545 After actnum,col2,col4 xxxxx , 0 , 0 xxxxx , 845, 0 xxxxx , 0 ,545 Any guidance would be appreciated

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  • How to improve the speed of a loop containing a sqlalchemy query statement as conditional

    - by LtPinback
    This loop checks if a record is in the sqlite database and builds a list of dictionaries for those records that are missing and then executes a multiple insert statement with the list. This works but it is very slow (at least i think it is slow) as it takes 5 minutes to loop over 3500 queries. I am a complete newbie in python, sqlite and sqlalchemy so I wonder if there is a faster way of doing this. list_dict = [] session = Session() for data in data_list: if session.query(Class_object).filter(Class_object.column_name_01 == data[2]).filter(Class_object.column_name_00 == an_id).count() == 0: list_dict.append({'column_name_00':a_id, 'column_name_01':data[2]}) conn = engine.connect() conn.execute(prices.insert(),list_dict) conn.close() session.close() edit: I moved session = Session() outside the loop. Did not make a difference.

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  • sending address of a variable declared on the stack?

    - by kobac
    I have a doubt concerning declaring variables, their scope, and if their address could be sent to other functions even if they are declared on the stack? class A{ AA a; void f1(){ B b; aa.f2(&b); } }; class AA{ B* mb; f2(B* b){ mb = b; //... } }; Afterwards, I use my AA::mb pointer in the code. So things I would like to know are following. When the program exits A::f1() function, b variable since declared as a local variable and placed on the stack, can't be used anymore afterwards. What happens with the validity of the AA::mb pointer? It contains the address of the local variable which could not be available anymore, so the pointer isn't valid anymore? If B class is a std::<vector>, and AA::mb is not a pointer anymore to that vector, but a vector collection itself for example. I would like to avoid copying all of it's contents in AA::f2() to a member AA::mb in line mb = b. Which solution would you recommend since I can't assign a pointer to it, because it'll be destroyed when the program exits AA::f2()

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  • Routing Skype call to another Voip company

    - by Anarchist
    Hello, As my project to do over this summer I would like to create a program that answers a Skype call using the Skype API and allows a user to connect to another VOIP provider (through SIP) and make calls by dialling through the client callers Skype application. I understand that the Skype API allows me to answer and receive keypad input, but I'm stuck on actually sending the sound of the call to a SIP client. Is there an API/library that would allow me to take the Skype receiving audio as input in the SIP client? Is this even possible? I'm not tied to a language but I had planned on using Python. Thanks.

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  • Use C function in C++ program; "multiply-defined" error

    - by eom
    I am trying to use this code for the Porter stemming algorithm in a C++ program I've already written. I followed the instructions near the end of the file for using the code as a separate module. I created a file, stem.c, that ends after the definition and has extern int stem(char * p, int i, int j) ... It worked fine in Xcode but it does not work for me on Unix with gcc 4.1.1--strange because usually I have no problem moving between the two. I get the error ld: fatal: symbol `stem(char*, int, int)' is multiply-defined: (file /var/tmp//ccrWWlnb.o type=FUNC; file /var/tmp//cc6rUXka.o type=FUNC); ld: fatal: File processing errors. No output written to cluster I've looked online and it seems like there are many things I could have wrong, but I'm not sure what combination of a header file, extern "C", etc. would work.

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  • Should we or should we not check in the classes folder in WEB-INF directory into SVN?

    - by Vatsala
    I use SVN, and am learning how to use it along with eclipse IDE. The first time I add classes to my package, there is no problem, the generated class files get into SVN smoothly. The moment I edit them, I get this message - "WEB-INF/classes" is obstructed. I try the "clean-up" command and the clean up command says "WEB-INF/classes" folder is locked. I use TortoiseSVN as my SVN client. I know why this is happening. It probably because the Eclipse overwrites all the files while generating classes and then causes this - Is it inappropriate to commit the class files into SVN? If not, what should I do to commit these class files smoothly?

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  • Python - a clean approach to this problem?

    - by Seafoid
    Hi, I am having trouble picking the best data structure for solving a problem. The problem is as below: I have a nested list of identity codes where the sublists are of varying length. li = [['abc', 'ghi', 'lmn'], ['kop'], ['hgi', 'ghy']] I have a file with two entries on each line; an identity code and a number. abc 2.93 ghi 3.87 lmn 5.96 Each sublist represents a cluster. I wish to select the i.d. from each sublist with the highest number associated with it, append that i.d. to a new list and ultimately write it to a new file. What data structure should the file with numbers be read in as? Also, how would you iterate over said data structure to return the i.d. with the highest number that matches the i.d. within a sublist? Thanks, S :-)

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  • command line arg?

    - by kaushik
    This is a module named XYZ. def func(x) ..... ..... if __name__=="__main__": print func(sys.argv[1]) Now I have imported this module in another code and want to use the func. How can i use it? import XYZ After this, where to give the argument, and syntax on how to call it, please?

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  • Understanding Scope on Scala's For Loops (For Comprehension)

    - by T. Stone
    In Chapter 3 of Programming Scala, the author gives two examples of for loops / for comprehensions, but switches between using ()'s and {}'s. Why is this the case, as these inherently look like they're doing the same thing? Is there a reason breed <- dogBreeds is on the 2nd line in example #2? // #1 ()'s for (breed <- dogBreeds if breed.contains("Terrier"); if !breed.startsWith("Yorkshire") ) println(breed) // #2 {}'s for { breed <- dogBreeds upcasedBreed = breed.toUpperCase() } println(upcasedBreed)

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  • C++: Question about freeing memory

    - by Martijn Courteaux
    On Learn C++, they wrote this to free memory: int *pnValue = new int; // dynamically allocate an integer *pnValue = 7; // assign 7 to this integer delete pnValue; pnValue = 0; My question is: "Is the last statement needed to free the memory correctly, completly?" I thought that the pointer *pnValue was still on the stack and new doesn't make any sense to the pointer. And if it is on the stack it will be cleaned up when the application leaves the scope (where the pointer is declared in), isn't it?

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  • Java: ListA.addAll(ListB) fires NullPointerException?

    - by HH
    The err part is Capitalized in the code, it also comes in foreaching. Because of the abstract list, it cannot be initialized, declaration is in a static field. The lists have the same type. import java.util.*; public class Test { public static final List<String> highPrio = Arrays.asList("*","/"); public static List<String> ops; public static void main(String[] args) { //ERROR HERE, why do it throw nullPointer? ops.addAll(highPrio); for(String s : ops) { System.out.println(s); } } }

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