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  • Question about main(String[] args) [migrated]

    - by Andrew0085
    I'm new to programming, and I'm using java. Here's a program I wrote: class HelloApp { static String hi; public static void main(String[] args) { int length = args.length; if (length > 0) { hi = args[0]; sayHi(); } } static void sayHi() { if (hi == "hello") { System.out.println("Hello!"); } } } My question is: Why doesn't inputting "java HelloApp hello" make "Hello!" appear on the next line?

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  • In PHP... best way to turn string representation of a folder structure into nested array

    - by Greg Frommer
    Hi everyone, I looked through the related questions for a similar question but I wasn't seeing quite what I need, pardon if this has already been answered already. In my database I have a list of records that I want represented to the user as files inside of a folder structure. So for each record I have a VARCHAR column called "FolderStructure" that I want to identify that records place in to the folder structure. The series of those flat FolderStructure string columns will create my tree structure with the folders being seperated by backslashes (naturally). I didn't want to add another table just to represent a folder structure... The 'file' name is stored in a separate column so that if the FolderStructure column is empty, the file is assumed to be at the root folder. What is the best way to turn a collection of these records into a series of HTML UL/LI tags... where each LI represents a file and each folder structure being an UL embedded inside it's parent?? So for example: file - folderStructure foo - bar - firstDir blue - firstDir/subdir would produce the following HTML: <ul> <li>foo</li> <ul> <li> bar </li> <ul> <li> blue </li> </ul> </ul> </ul> Thanks

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  • Why is my PHP string being converted to 1?

    - by animuson
    Ok, so here's the quick rundown. I have a function to generate the page numbers. This: <?php die($ani->e->tmpl->pages("/archive", 1, 15, 1, true)); ?> will output Single Page like expected. But this: <?php $page_numbers = $ani->e->tmpl->pages("/archive", 1, 15, 1, true); ?> <?= $page_numbers ?> will output a simple 1 to the page. Why is it getting converted to a 1? I would expect it to store the 'Single Page' string to the page_numbers variable and then output it (like an echo) exactly the same. EDIT: Running a var_dump($page_numbers) returns int(1)... Here is the entire function in context: <?php // other functions... function show_list() { global $ani; $page_numbers = $ani->e->tmpl->pages("/archive", 1, 15, 1, true); ob_start(); ?> <!-- content:start --> <?php $archive_result = $ani->e->db->build(array("select" => "*", "from" => "animuson_archive", "orderby" => "0-time", "limit" => 15)); while ($archive = $ani->e->db->fetch($archive_result)) { ?> <h2><a href="/archive/article/<?= $archive['aid'] ?>/<?= $archive['title_nice'] ?>"><?= $archive['title'] ?></a></h2> <!-- breaker --> <?php } ?> <?= var_dump($page_numbers) ?> <!-- content:stop --> <?php $ani->e->tmpl->process("box", ob_get_clean()); } // other functions... ?>

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  • General String Encryption in .NET

    - by cryptospin
    I am looking for a general string encryption class in .NET. (Not to be confused with the 'SecureString' class.) I have started to come up with my own class, but thought there must be a .NET class that already allows you to encrypt/decrypt strings of any encoding with any Cryptographic Service Provider. Public Class SecureString Private key() As Byte Private iv() As Byte Private m_SecureString As String Public ReadOnly Property Encrypted() As String Get Return m_SecureString End Get End Property Public ReadOnly Property Decrypted() As String Get Return Decrypt(m_SecureString) End Get End Property Public Sub New(ByVal StringToSecure As String) If StringToSecure Is Nothing Then StringToSecure = "" m_SecureString = Encrypt(StringToSecure) End Sub Private Function Encrypt(ByVal StringToEncrypt As String) As String Dim result As String = "" Dim bytes() As Byte = Text.Encoding.UTF8.GetBytes(StringToEncrypt) Using provider As New AesCryptoServiceProvider() With provider .Mode = CipherMode.CBC .GenerateKey() .GenerateIV() key = .Key iv = .IV End With Using ms As New IO.MemoryStream Using cs As New CryptoStream(ms, provider.CreateEncryptor(), CryptoStreamMode.Write) cs.Write(bytes, 0, bytes.Length) cs.FlushFinalBlock() End Using result = Convert.ToBase64String(ms.ToArray()) End Using End Using Return result End Function Private Function Decrypt(ByVal StringToDecrypt As String) As String Dim result As String = "" Dim bytes() As Byte = Convert.FromBase64String(StringToDecrypt) Using provider As New AesCryptoServiceProvider() Using ms As New IO.MemoryStream Using cs As New CryptoStream(ms, provider.CreateDecryptor(key, iv), CryptoStreamMode.Write) cs.Write(bytes, 0, bytes.Length) cs.FlushFinalBlock() End Using result = Text.Encoding.UTF8.GetString(ms.ToArray()) End Using End Using Return result End Function End Class

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  • Faster way to split a string and count characters using R?

    - by chrisamiller
    I'm looking for a faster way to calculate GC content for DNA strings read in from a FASTA file. This boils down to taking a string and counting the number of times that the letter 'G' or 'C' appears. I also want to specify the range of characters to consider. I have a working function that is fairly slow, and it's causing a bottleneck in my code. It looks like this: ## ## count the number of GCs in the characters between start and stop ## gcCount <- function(line, st, sp){ chars = strsplit(as.character(line),"")[[1]] numGC = 0 for(j in st:sp){ ##nested ifs faster than an OR (|) construction if(chars[[j]] == "g"){ numGC <- numGC + 1 }else if(chars[[j]] == "G"){ numGC <- numGC + 1 }else if(chars[[j]] == "c"){ numGC <- numGC + 1 }else if(chars[[j]] == "C"){ numGC <- numGC + 1 } } return(numGC) } Running Rprof gives me the following output: > a = "GCCCAAAATTTTCCGGatttaagcagacataaattcgagg" > Rprof(filename="Rprof.out") > for(i in 1:500000){gcCount(a,1,40)}; > Rprof(NULL) > summaryRprof(filename="Rprof.out") self.time self.pct total.time total.pct "gcCount" 77.36 76.8 100.74 100.0 "==" 18.30 18.2 18.30 18.2 "strsplit" 3.58 3.6 3.64 3.6 "+" 1.14 1.1 1.14 1.1 ":" 0.30 0.3 0.30 0.3 "as.logical" 0.04 0.0 0.04 0.0 "as.character" 0.02 0.0 0.02 0.0 $by.total total.time total.pct self.time self.pct "gcCount" 100.74 100.0 77.36 76.8 "==" 18.30 18.2 18.30 18.2 "strsplit" 3.64 3.6 3.58 3.6 "+" 1.14 1.1 1.14 1.1 ":" 0.30 0.3 0.30 0.3 "as.logical" 0.04 0.0 0.04 0.0 "as.character" 0.02 0.0 0.02 0.0 $sampling.time [1] 100.74 Any advice for making this code faster?

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  • Search a string in a file and write the matched lines to another file in Java

    - by Geeta
    For searching a string in a file and writing the lines with matched string to another file it takes 15 - 20 mins for a single zip file of 70MB(compressed state). Is there any ways to minimise it. my source code: getting Zip file entries zipFile = new ZipFile(source_file_name); entries = zipFile.entries(); while (entries.hasMoreElements()) { ZipEntry entry = (ZipEntry)entries.nextElement(); if (entry.isDirectory()) { continue; } searchString(Thread.currentThread(),entry.getName(), new BufferedInputStream (zipFile.getInputStream(entry)), Out_File, search_string, stats); } zipFile.close(); Searching String public void searchString(Thread CThread, String Source_File, BufferedInputStream in, File outfile, String search, String stats) throws IOException { int count = 0; int countw = 0; int countl = 0; String s; String[] str; BufferedReader br2 = new BufferedReader(new InputStreamReader(in)); System.out.println(CThread.currentThread()); while ((s = br2.readLine()) != null) { str = s.split(search); count = str.length - 1; countw += count; //word count if (s.contains(search)) { countl++; //line count WriteFile(CThread,s, outfile.toString(), search); } } br2.close(); in.close(); } -------------------------------------------------------------------------------- public void WriteFile(Thread CThread,String line, String out, String search) throws IOException { BufferedWriter bufferedWriter = null; System.out.println("writre thread"+CThread.currentThread()); bufferedWriter = new BufferedWriter(new FileWriter(out, true)); bufferedWriter.write(line); bufferedWriter.newLine(); bufferedWriter.flush(); } Please help me. Its really taking 40 mins for 10 files using threads and 15 - 20 mins for a single file of 70MB after being compressed. Any ways to minimise the time.

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  • Show random string.

    - by zaid
    i am trying to display a random string each time a button is pressed from a set of strings defined in strings.xml . this is an example of the strings ID's <string name="q0"> <string name="q1"> <string name="q2"> <string name="q3"> <string name="q4"> java code for getting a random string. private static final Random rgenerator = null; int RandomQ = R.string.q0 (rgenerator.nextInt(5) + 1); String q = getString(RandomQ); if i try to use this java code i get an error at "q0" in R.string.q0 which is The method q0(int) is undefined for the type R.string if i try to use the quick fix and create a method, it works. but it wont let me save or run the app because it replaces my create method and shows this message R.java was modified manually! Reverting to generated version! thanks for reading.

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  • How to mock a String using mockito?

    - by Alceu Costa
    I need to simulate a test scenario in which I call the getBytes() method of a String object and I get an UnsupportedEncodingException. I have tried to achieve that using the following code: String nonEncodedString = mock(String.class); when(nonEncodedString.getBytes(anyString())).thenThrow(new UnsupportedEncodingException("Parsing error.")); The problem is that when I run my test case I get a MockitoException that says that I can't mock a java.lang.String class. Is there a way to mock a String object using mockito or, alternatively, a way to make my String object throw an UnsupportedEncodingException when I call the getBytes method? Here are more details to illustrate the problem: This is the class that I want to test: public final class A{ public static String f(String str){ try{ return new String(str.getBytes("UTF-8")); } catch (UnsupportedEncodingException e) { // This is the catch block that I want to exercise. ... } } } This is my testing class (I'm using JUnit 4 and mockito): public class TestA { @Test(expected=UnsupportedEncodingException.class) public void test(){ String aString = mock(String.class); when(nonEncodedString.getBytes(anyString())).thenThrow(new UnsupportedEncodingException("Parsing error.")); A.f(aString); } }

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  • [nHibernate] casting string to bool using nHibernate Criteria

    - by code-zoop
    I have an nHibernate query using Criteria, and I am trying to cast a string to bool in the query itself. I have done the same with casting a string to int, and that works well (the "DataField" property is "1" as a string): var result = Session .CreateCriteria<Car>() .Add(Restrictions.Eq((Projections.Cast(NHibernateUtil.Int32, Projections.Property("DataField"), 1)) .List<Car>(); tx.Commit(); But I am trying to do the same with bool, but I do not get the expected result: var result = Session .CreateCriteria<Car>() .Add(Restrictions.Eq((Projections.Cast(NHibernateUtil.bool, Projections.Property("DataField"), true)) .List<Car>(); tx.Commit(); "DataField" is the string "True", but the result in an empty list, where it should contain 100 elements with the "DataField" property string set to "True". I have tried with the string "true", and "1", but the result is still an empty List. [EDIT] As Commented below, I could check for the string "True" or "False", but I would say this is a more general question than just for the Boolean. Note that the idea is to have some sort of key value representation of the data, where the value can be different data types. I need the value table to contain all data, so storing the data as string seems like the cleanest solution! I have been able to use the method above to store both int and double as string, and to the cast in the query, but I have not succeeded using the same method for DateDime and Boolean. And for DateTime it is crucial to have the actual DateTime object. How can I make the cast from string to bool, and string to DateTime work in the queries? Thanks

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  • In perl, how can I call a method whose name I have in a string?

    - by Ryan Thompson
    I'm trying to write some abstract code for searching through a list of similar objects for the first one whose attributes match specific values. In order to do this, I need to call a bunch of accessor methods and check all their values one by one. I'd like to use an abstraction like this: sub verify_attribute { my ($object, $attribute_method, $wanted_value) = @_; if ( call_method($object, $attribute_method) ~~ $wanted_value ) { return 1; } else { return; } } Then I can loop through a hash whose keys are accessor method names and whose values are the values I'm looking for for those attributes. For example, if that hash is called %wanted, I might use code like this to find the object I want: my $found_object; FINDOBJ: foreach my $obj (@list_of_objects) { foreach my $accessor (keys %wanted) { next FINDOBJ unless verify_attribute($obj, $accessor, $wanted{$accessor}); } # All attrs verified $found_object = $obj; last FINDOBJ; } Of course, the only problem is that call_method does not exsit. Or does it? How can I call a method if I have a string containing its name? Or is there a better solution to this whole problem?

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  • How can I parse_url in PHP when there is a URL in a string variable?

    - by Eric O
    I am admittedly a PHP newbie, so I need some help. I am creating a self-designed affiliate program for my site and have the option for an affiliate to add a SubID to their link for tracking. Without having control over what is entered, I have been testing different scenarios and found a bug when a full URL is entered (i.e. "http://example.com"). In my PHP I can grab the variable from the string no problem. My problem comes from when I get the referring URL and parse it (since I need to parse the referring URL to get the host mane for other uses). Code below: $refURL = getenv("HTTP_REFERER"); $parseRefURL = parse_url($refURL); WORKS when incoming link is (for example): http://example.com/?ref=REFERRER'S-ID&sid=www.test.com ERROR when incoming link is (notice the addition of "http://" after "sid="): http://example.com/?ref=REFERRER'S-ID&sid=http://www.test.com Here is the warning message: Warning: parse_url(/?ref=REFERRER'S-ID&sid=http://www.test.com) [function.parse-url]: Unable to parse url in /home4/'directory'/public_html/hosterdoodle/header.php on line 28 Any ideas on how to keep the parse-url function from being thrown off when someone may decide to place a URL in a variable? (I actually tested this problem down to the point that it will throw the error with as little as ":/" in the variable)

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  • How string accepting interface should look like?

    - by ybungalobill
    Hello, This is a follow up of this question. Suppose I write a C++ interface that accepts or returns a const string. I can use a const char* zero-terminated string: void f(const char* str); // (1) The other way would be to use an std::string: void f(const string& str); // (2) It's also possible to write an overload and accept both: void f(const char* str); // (3) void f(const string& str); Or even a template in conjunction with boost string algorithms: template<class Range> void f(const Range& str); // (4) My thoughts are: (1) is not C++ish and may be less efficient when subsequent operations may need to know the string length. (2) is bad because now f("long very long C string"); invokes a construction of std::string which involves a heap allocation. If f uses that string just to pass it to some low-level interface that expects a C-string (like fopen) then it is just a waste of resources. (3) causes code duplication. Although one f can call the other depending on what is the most efficient implementation. However we can't overload based on return type, like in case of std::exception::what() that returns a const char*. (4) doesn't work with separate compilation and may cause even larger code bloat. Choosing between (1) and (2) based on what's needed by the implementation is, well, leaking an implementation detail to the interface. The question is: what is the preffered way? Is there any single guideline I can follow? What's your experience?

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  • Splitting a string which contain multiple symbols to get specific values

    - by Eon Rusted du Plessis
    I cannot believe I am having trouble with this following string String filter = "name=Default;pattern=%%;start=Last;end=Now"; This is a short and possibly duplicate question, but how would I split this string to get: string Name = "Default"; string Pattern = "%%" ; string start = "Last" ; string end = "Now" ; Reason why I ask is my deadline is very soon, and this is literally the last thing I must do. I'm Panicking, and I'm stuck on this basic command. I tried: pattern = filter.Split(new string[] { "pattern=", ";" }, StringSplitOptions.RemoveEmptyEntries)[1]; //Gets the pattern startDate = filter.Split(new string[] { "start=", ";" }, StringSplitOptions.RemoveEmptyEntries)[1]; //Gets the start date I happen to get the pattern which I needed, but as soon as I try to split start, I get the value as "Pattern=%%" What can I do? Forgot to mention The list in this string which needs splitting may not be in any particular order . this is a single sample of a string which will be read out of a stringCollection (reading these filters from Properties.Settings.Filters

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  • Is is possible to stringstream this way? to convert from string to int?

    - by John
    Is it possible to stringstream like this? I am trying to read with ifstream and convert it. string things = "10 11 12 -10"; int i1; int i2; int i3; int i4; stringstream into; into << things; into >> i1; into >> i2; into >> i3; into >> i4; I expect it to be : i1 = 10 i2 = 11 i3 = 12 i4 = -10 is that correct? Can the same stringstream variable be used multiple times? When I tried, the first time was ok but everything else later on is just 0.

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  • How to put data from List<string []> to dataGridView

    - by Kirill
    Try to put some data from List to dataGridView, but have some problem with it. Currently have method, that return me required List - please see picture below code public List<string[]> ReadFromFileBooks() { List<string> myIdCollection = new List<string>(); List<string[]> resultColl = new List<string[]>(); if (chooise == "all") { if (File.Exists(filePath)) { using (FileStream fs = new FileStream(filePath, FileMode.Open, FileAccess.Read)) { StreamReader sr = new StreamReader(fs); string[] line = sr.ReadToEnd().Split(new string[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries); foreach (string l in line) { string[] result = l.Split(','); foreach (string element in result) { myIdCollection.Add(element); } resultColl.Add(new string[] { myIdCollection[0], myIdCollection[1], myIdCollection[2], myIdCollection[3] }); myIdCollection.Clear(); } sr.Close(); return resultColl; } } .... this return to me required data in requred form (like list from arrays). After this, try to move it to the dataGridView, that already have 4 columns with names (because i'm sure, that no than 4 colums required) - please see pic below Try to put data in to dataGridView using next code private void radioButtonViewAll_CheckedChanged(object sender, EventArgs e) { TxtLibrary myList = new TxtLibrary(filePathBooks); myList.chooise = "all"; //myList.ReadFromFileBooks(); DataTable table = new DataTable(); foreach (var array in myList.ReadFromFileBooks()) { table.Rows.Add(array); } dataGridViewLibrary.DataSource = table; } But as result got error - "required more rows that exist in dataGridVIew", but accordint to what I'm see (pic above) q-ty of rows (4) equal q-ty of arrays element in List (4). Try to check result by putting additional temp variables - but it's ok - please see pic below Where I'm wrong? Maybe i use dataGridView not in correct way?

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  • How to convert object to string list?

    - by user1381501
    I want to get two values by using linq select query and try to convert object to string list. I am trying to convert list to list. The code as below. I got the error when I convert object to string list : return returnvalue = (List)userlist; public List<string> GetUserList(string username) { List<User> UserList = new List<User>(); List<string> returnvalue=new List<string>(); try { string returnstring = string.Empty; DataTable dt = null; dt = Library.Helper.FindUser(username, 200); foreach (DataRow dr in dt.Rows) { User user = new User(); spuser.id = dr["ID"].ToString(); spuser.name = dr["Name"].ToString(); UserList.Adduser } } catch (Exception ex) { } List<SharePointMentoinUser> userlist = UserList.Select(a => new User { name = (string)a.name, id = (string)a.id }).ToList(); **return returnvalue = (List<string>)userlist;** }

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  • MIPS: removing non alpha-numeric characters from a string

    - by Kron
    I'm in the process of writing a program in MIPS that will determine whether or not a user entered string is a palindrome. It has three subroutines which are under construction. Here is the main block of code, subroutines to follow with relevant info: .data Buffer: .asciiz " " # 80 bytes in Buffer intro: .asciiz "Hello, please enter a string of up to 80 characters. I will then tell you if that string was a palindrome!" .text main: li $v0, 4 # print_string call number la $a0, intro # pointer to string in memory syscall li $v0, 8 #syscall code for reading string la $a0, Buffer #save read string into buffer li $a1, 80 #string is 80 bytes long syscall li $s0, 0 #i = 0 li $t0, 80 #max for i to reach la $a0, Buffer jal stripNonAlpha li $v0, 4 # print_string call number la $a0, Buffer # pointer to string in memory syscall li $s0, 0 jal findEnd jal toUpperCase li $v0, 4 # print_string call number la $a0, Buffer # pointer to string in memory syscall Firstly, it's supposed to remove all non alpha-numeric characters from the string before hand, but when it encounters a character designated for removal, all characters after that are removed. stripNonAlpha: beq $s0, $t0, stripEnd #if i = 80 end add $t4, $s0, $a0 #address of Buffer[i] in $t4 lb $s1, 0($t4) #load value of Buffer[i] addi $s0, $s0, 1 #i = i + 1 slti $t1, $s1, 48 #if ascii code is less than 48 bne $t1, $zero, strip #remove ascii character slti $t1, $s1, 58 #if ascii code is greater than 57 #and slti $t2, $s1, 65 #if ascii code is less than 65 slt $t3, $t1, $t2 bne $t3, $zero, strip #remove ascii character slti $t1, $s1, 91 #if ascii code is greater than 90 #and slti $t2, $s1, 97 #if ascii code is less than 97 slt $t3, $t1, $t2 bne $t3, $zero, strip #remove ascii character slti $t1, $s1, 123 #if ascii character is greater than 122 beq $t1, $zero, strip #remove ascii character j stripNonAlpha #go to stripNonAlpha strip: #add $t5, $s0, $a0 #address of Buffer[i] in $t5 sb $0, 0($t4) #Buffer[i] = 0 #addi $s0, $s0, 1 #i = i + 1 j stripNonAlpha #go to stripNonAlpha stripEnd: la $a0, Buffer #save modified string into buffer jr $ra #return Secondly, it is supposed to convert all lowercase characters to uppercase. toUpperCase: beq $s0, $s2, upperEnd add $t4, $s0, $a0 lb $s1, 0($t4) addi $s1, $s1, 1 slti $t1, $s1, 97 #beq $t1, $zero, upper slti $t2, $s1, 123 slt $t3, $t1, $t2 bne $t1, $zero, upper j toUpperCase upper: add $t5, $s0, $a0 addi $t6, $t6, -32 sb $t6, 0($t5) j toUpperCase upperEnd: la $a0, Buffer jr $ra The final subroutine, which checks if the string is a palindrome isn't anywhere near complete at the moment. I'm having trouble finding the end of the string because I'm not sure what PC-SPIM uses as the carriage return character. Any help is appreciated, I have the feeling most of my problems result from something silly and stupid so feel free to point out anything, no matter how small.

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  • Is there a standard format string in ASP.NET to convert 1/2/3/... to 1st/2nd/3rd...?

    - by Dr. Monkey
    I have an integer in an Access database, which is being displayed in ASP.NET. The integer represents the position achieved by a competitor in a sporting event (1st, 2nd, 3rd, etc.), and I'd like to display it with a standard suffix like 'st', 'nd', 'rd' as appropriate, rather than just a naked number. An important limitation is that this is for an assignment which specifies that no VB or C# code be written (in fact it instructs code behind files to be deleted entirely). Ideally I'd like to use a standard format string if available, otherwise perhaps a custom string (I haven't worked with format strings much, and this isn't high enough priority to dedicate significant time to*, but I am very curious about whether there's a standard string for this). (* The assignment is due tonight, and I've learned the hard way that I can't afford to spend time on things that don't get the marks, even if they irk me significantly.)

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  • SQL SERVER – Concat Function in SQL Server – SQL Concatenation

    - by pinaldave
    Earlier this week, I was delivering Advanced BI training on the subject of “SQL Server 2008 R2″. I had great time delivering the session. During the session, we talked about SQL Server 2010 Denali. Suddenly one of the attendees suggested his displeasure for the product. He said, even though, SQL Server is now in moving very fast and have proved many times a good enterprise solution, it does not have some basic functions. I naturally asked him for example and he suggested CONCAT() which exists in MySQL and Oracle. The answer is very simple – the equalent function in SQL Server to CONCAT() is ‘+’ (plus operator without quotes). Method 1: Concatenating two strings SELECT 'FirstName' + ' ' + 'LastName' AS FullName Method 2: Concatenating two Numbers SELECT CAST(1 AS VARCHAR(10)) + 'R' + CAST(2 AS VARCHAR(10)) Method 3: Concatenating values from table columns SELECT FirstName + ' ' + LastName FROM AdventureWorks.Person.Contact Well, this may look very simple but sometime it is very difficult to find the information for simple things only. Do you have any such example which you would like to share with community? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL String, SQL Tips and Tricks, T SQL, Technology

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  • How to verify the Liskov substitution principle in an inheritance hierarchy?

    - by Songo
    Inspired by this answer: Liskov Substitution Principle requires that Preconditions cannot be strengthened in a subtype. Postconditions cannot be weakened in a subtype. Invariants of the supertype must be preserved in a subtype. History constraint (the "history rule"). Objects are regarded as being modifiable only through their methods (encapsulation). Since subtypes may introduce methods that are not present in the supertype, the introduction of these methods may allow state changes in the subtype that are not permissible in the supertype. The history constraint prohibits this. I was hoping if someone would post a class hierarchy that violates these 4 points and how to solve them accordingly. I'm looking for an elaborate explanation for educational purposes on how to identify each of the 4 points in the hierarchy and the best way to fix it. Note: I was hoping to post a code sample for people to work on, but the question itself is about how to identify the faulty hierarchies :)

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  • Android SQLiteConstraintException: error code 19: constraint failed

    - by Tom D
    I've seen other questions about this exception, but all of them seem to be resolved with the solution that a row with the primary key specified already exists. This doesn't seem to be the case for me. I have tried replacing all single quotes in my strings with double quotes, but the same problem occurs. I'm trying to insert a row into the Settings table of the SQLite database I've created by doing the following: db.execSQL("DROP TABLE IF EXISTS "+Settings.SETTINGS_TABLE_NAME + ";"); db.execSQL(CREATE_MEDIA_TABLE); db.execSQL(CREATE_SETTINGS_TABLE); Cursor c = getAllSettings(); //If there isn't already a settings row, create a row full of defaults if(c.getCount()==0){ ContentValues cv = new ContentValues(); cv.put(Settings.SETTING_UNIQUE_ID, "'"+Settings.uniqueID+"'"); cv.put(Settings.SETTING_DEVICE_ID, Settings.SETTING_DEVICE_ID_DEFAULT); cv.put(Settings.SETTING_CONNECTION_PREFERENCE, Settings.SETTING_CONNECTION_PREFERENCE_DEFAULT); cv.put(Settings.SETTING_AD_HOC_ENABLED, Settings.SETTING_AD_HOC_ENABLED_DEFAULT); cv.put(Settings.SETTING_SERVER_ADDRESS, Settings.SETTING_SERVER_ADDRESS_DEFAULT); cv.put(Settings.SETTING_RECORDING_MODE, Settings.SETTING_RECORDING_MODE_DEFAULT); cv.put(Settings.SETTING_PREVIEW_ENABLED, Settings.SETTING_PREVIEW_ENABLED_DEFAULT); cv.put(Settings.SETTING_PICTURE_RESOLUTION_X, Settings.SETTING_PICTURE_RESOLUTION_X_DEFAULT); cv.put(Settings.SETTING_PICTURE_RESOLUTION_Y, Settings.SETTING_PICTURE_RESOLUTION_Y_DEFAULT); cv.put(Settings.SETTING_VIDEO_RESOLUTION_X, Settings.SETTING_VIDEO_RESOLUTION_X_DEFAULT); cv.put(Settings.SETTING_VIDEO_RESOLUTION_Y, Settings.SETTING_VIDEO_RESOLUTION_Y_DEFAULT); cv.put(Settings.SETTING_VIDEO_FPS, Settings.SETTING_VIDEO_FPS_DEFAULT); cv.put(Settings.SETTING_AUDIO_BITRATE_KBPS, Settings.SETTING_AUDIO_BITRATE_KBPS_DEFAULT); cv.put(Settings.SETTING_STORE_TO_SD, Settings.SETTING_STORE_TO_SD_DEFAULT); cv.put(Settings.SETTING_STORAGE_LIMIT_MB, Settings.SETTING_STORAGE_LIMIT_MB_DEFAULT); this.db.insert(Settings.SETTINGS_TABLE_NAME, null, cv); } The CREATE_SETTINGS_TABLE string is defined as the following: private static String CREATE_SETTINGS_TABLE = "CREATE TABLE IF NOT EXISTS " + Settings.SETTINGS_TABLE_NAME + "(" + Settings.SETTING_UNIQUE_ID + " TEXT NOT NULL PRIMARY KEY, " + Settings.SETTING_DEVICE_ID + " TEXT NOT NULL , " + Settings.SETTING_CONNECTION_PREFERENCE + " TEXT NOT NULL CHECK("+Settings.SETTING_CONNECTION_PREFERENCE+" IN("+Settings.SETTING_CONNECTION_PREFERENCE_ALLOWED+")), " + Settings.SETTING_AD_HOC_ENABLED + " TEXT NOT NULL CHECK("+Settings.SETTING_AD_HOC_ENABLED+" IN("+Settings.SETTING_AD_HOC_ENABLED_ALLOWED+")), " + Settings.SETTING_SERVER_ADDRESS + " TEXT NOT NULL, " + Settings.SETTING_RECORDING_MODE + " TEXT NOT NULL CHECK("+Settings.SETTING_RECORDING_MODE+" IN("+Settings.SETTING_RECORDING_MODE_ALLOWED+")), " + Settings.SETTING_PREVIEW_ENABLED + " TEXT NOT NULL CHECK("+Settings.SETTING_PREVIEW_ENABLED+" IN("+Settings.SETTING_PREVIEW_ENABLED_ALLOWED+")), " + Settings.SETTING_PICTURE_RESOLUTION_X + " TEXT NOT NULL, " + Settings.SETTING_PICTURE_RESOLUTION_Y + " TEXT NOT NULL, " + Settings.SETTING_VIDEO_RESOLUTION_X + " TEXT NOT NULL, " + Settings.SETTING_VIDEO_RESOLUTION_Y + " TEXT NOT NULL, " + Settings.SETTING_VIDEO_FPS + " TEXT NOT NULL, " + Settings.SETTING_AUDIO_BITRATE_KBPS + " TEXT NOT NULL, " + Settings.SETTING_STORE_TO_SD + " TEXT NOT NULL CHECK("+Settings.SETTING_STORE_TO_SD+" IN("+Settings.SETTING_STORE_TO_SD_ALLOWED+")), " + Settings.SETTING_STORAGE_LIMIT_MB + " TEXT NOT NULL )"; However, when I execute my insert, I always get: 03-19 19:37:36.974: ERROR/Database(386): Error inserting server_address='0.0.0.0' storage_limit='-1' connection='none' preview_enabled='0' sd_enabled='1' video_fps='15' audio_bitrate='96' device_id='-1' recording_mode='none' picture_resolution_x='-1' picture_resolution_y='-1' unique_id='000000000000000' adhoc_enable='0' video_resolution_x='320' video_resolution_y='240' 03-19 19:45:34.284: ERROR/Database(446): android.database.sqlite.SQLiteConstraintException: error code 19: constraint failed It seems as if all the columns in my insert are not null. The row's primary key HAS to be unique, because it's the only row in the table. Therefore, the only thing I can think of is my CHECK conditions aren't true. Here are the predefined strings I'm using: public static final String SETTING_UNIQUE_ID = "unique_id"; public static final String SETTING_DEVICE_ID = "device_id"; public static final String SETTING_DEVICE_ID_DEFAULT = "'-1'"; public static final String SETTING_CONNECTION_PREFERENCE = "connection"; public static final String SETTING_CONNECTION_PREFERENCE_3G = "'3g'"; public static final String SETTING_CONNECTION_PREFERENCE_WIFI = "'wifi'"; public static final String SETTING_CONNECTION_PREFERENCE_NONE = "'none'"; public static final String SETTING_CONNECTION_PREFERENCE_ALLOWED = SETTING_CONNECTION_PREFERENCE_3G+","+SETTING_CONNECTION_PREFERENCE_WIFI+","+SETTING_CONNECTION_PREFERENCE_NONE; public static final String SETTING_CONNECTION_PREFERENCE_DEFAULT = SETTING_CONNECTION_PREFERENCE_NONE; public static final String SETTING_AD_HOC_ENABLED = "adhoc_enable"; public static final String SETTING_AD_HOC_ENABLED_ALLOWED = TRUE+","+FALSE; public static final String SETTING_AD_HOC_ENABLED_DEFAULT = FALSE; public static final String SETTING_SERVER_ADDRESS = "server_address"; public static final String SETTING_SERVER_ADDRESS_DEFAULT = "'0.0.0.0'"; public static final String SETTING_RECORDING_MODE = "recording_mode"; public static final String SETTING_RECORDING_MODE_VIDEO = "'video'"; public static final String SETTING_RECORDING_MODE_AUDIO = "'audio'"; public static final String SETTING_RECORDING_MODE_PICTURE = "'picture'"; public static final String SETTING_RECORDING_MODE_NONE = "'none'"; public static final String SETTING_RECORDING_MODE_ALLOWED = SETTING_RECORDING_MODE_VIDEO+","+SETTING_RECORDING_MODE_AUDIO+","+SETTING_RECORDING_MODE_PICTURE+","+SETTING_RECORDING_MODE_NONE; public static final String SETTING_RECORDING_MODE_DEFAULT = SETTING_RECORDING_MODE_NONE; public static final String SETTING_PREVIEW_ENABLED = "preview_enabled"; public static final String SETTING_PREVIEW_ENABLED_ALLOWED = TRUE+","+FALSE; public static final String SETTING_PREVIEW_ENABLED_DEFAULT = FALSE; public static final String SETTING_PICTURE_RESOLUTION_X = "picture_resolution_x"; public static final String SETTING_PICTURE_RESOLUTION_X_DEFAULT = "'-1'"; public static final String SETTING_PICTURE_RESOLUTION_Y = "picture_resolution_y"; public static final String SETTING_PICTURE_RESOLUTION_Y_DEFAULT = "'-1'"; public static final String SETTING_VIDEO_RESOLUTION_X = "video_resolution_x"; public static final String SETTING_VIDEO_RESOLUTION_X_DEFAULT = "'320'"; public static final String SETTING_VIDEO_RESOLUTION_Y = "video_resolution_y"; public static final String SETTING_VIDEO_RESOLUTION_Y_DEFAULT = "'240'"; public static final String SETTING_VIDEO_FPS = "video_fps"; public static final String SETTING_VIDEO_FPS_DEFAULT = "'15'"; public static final String SETTING_AUDIO_BITRATE_KBPS = "audio_bitrate"; public static final String SETTING_AUDIO_BITRATE_KBPS_DEFAULT = "'96'"; public static final String SETTING_STORE_TO_SD = "sd_enabled"; public static final String SETTING_STORE_TO_SD_ALLOWED = TRUE+","+FALSE; public static final String SETTING_STORE_TO_SD_DEFAULT = TRUE; public static final String SETTING_STORAGE_LIMIT_MB = "storage_limit"; public static final String SETTING_STORAGE_LIMIT_MB_DEFAULT = "'-1'"; public static final String SETTING_CLIP_LENGTH_SECONDS = "clip_length"; public static final String SETTING_CLIP_LENGTH_SECONDS_DEFAULT = "'300'"; Does anyone see what could be going on? I'm stumped. Thanks in advance.

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  • Ubuntu 12.04 Hp G72 Problem Installing proprietary wireless driver

    - by user69402
    I have a fresh Ubuntu 12.04 installed on HP G72 machine. In order for my wireless to work I need the proprietary driver installed - Broadcom STA wireless driver. Trying to install it from the System Settings gives me the error: "Sorry, installation of this driver failed. Please have a look at the log file for details: /var/log/jockey.log". So far I suspect the error to be caused by the bad "bcmwl-kernel-source" installation. What i tried: 1. remove "bcmwl-kernel-source" 2. install "bcmwl-kernel-source" installation through the terminal ends with "error code (1)". I would greatly appreciate any help Here is everything that the terminal returns: Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: bcmwl-kernel-source 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. Need to get 0 B/1,151 kB of archives. After this operation, 3,514 kB of additional disk space will be used. Selecting previously unselected package bcmwl-kernel-source. (Reading database ... 170331 files and directories currently installed.) Unpacking bcmwl-kernel-source (from .../bcmwl-kernel-source_5.100.82.38+bdcom-0ubuntu6.1_amd64.deb) ... Setting up bcmwl-kernel-source (5.100.82.38+bdcom-0ubuntu6.1) ... Loading new bcmwl-5.100.82.38+bdcom DKMS files... /usr/sbin/dkms: line 467: unset: POST_REMOVE$PRE_BUMLD': not a valid identifier /usr/sbin/dkms: line 467: unset:BUILD_E\CLUWIVE_ARCH': not a valid identifier /usr/sbin/dkms: line 467: unset: $': not a valid identifier /usr/sbin/dkms: line 467: unset:$': not a valid identifier /usr/sbin/dkms: line 467: unset: modules_conf_arra}': not a valid identifier /usr/sbin/dkms: line 467: unset:$': not a valid identifier /usr/sbin/dkms: line 467: unset: $': not a valid identifier /usr/sbin/dkms: line 467: unset:$': not a valid identifier /usr/sbin/dkms: line 467: unset: $': not a valid identifier /usr/sbin/dkms: line 467: unset:$': not a valid identifier /usr/sbin/dkms: line 467: unset: `$': not a valid identifier /usr/sbin/dkms: line 419: ${!POST_REMOVE$PRE_BUMLD[@]}: bad substitution /usr/sbin/dkms: line 419: ${!BUILD_E\CLUWIVE_ARCH[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution /usr/sbin/dkms: line 419: ${!$[@]}: bad substitution malloc: ../bash/subst.c:3671: assertion botched free: start and end chunk sizes differ Aborting.../tmp/tmp.pEXTnftUfI: line 4: modules_conf_arra}[[@]}]=[[@]}]}: command not found dkms.conf: Error! No 'DEST_MODULE_LOCATION' directive specified for record #0. dkms.conf: Error! Directive 'DEST_MODULE_LOCATION' does not begin with '/kernel', '/updates', or '/extra' in record #0. dkms.conf: Error! No 'PACKAGE_VERSION' directive specified. Error! Bad conf file. File: /usr/src/bcmwl-5.100.82.38+bdcom/dkms.conf does not represent a valid dkms.conf file. dpkg: error processing bcmwl-kernel-source (--configure): subprocess installed post-installation script returned error exit status 8 Errors were encountered while processing: bcmwl-kernel-source E: Sub-process /usr/bin/dpkg returned an error code (1)

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  • True / false evaluation doesn't work as expected in Scheme

    - by ron
    I'm trying to compare two booleans : (if (equal? #f (string->number "123b")) "not a number" "indeed a number") When I run this in the command line of DrRacket I get "not a number" , however , when I put that piece of code in my larger code , the function doesn't return that string ("not a number") , here's the code : (define (testing x y z) (define badInput "ERROR") (if (equal? #f (string->number "123b")) "not a number" "indeed a number") (display x)) And from command line : (testing "123" 1 2) displays : 123 Why ? Furthermore , how can I return a value , whenever I choose ? Here is my "real" problem : I want to do some input check to the input of the user , but the thing is , that I want to return the error message if I need , before the code is executed , because if won't - then I would run the algorithm of my code for some incorrect input : (define (convert originalNumber s_oldBase s_newBase) (define badInput "ERROR") ; Input check - if one of the inputs is not a number then return ERROR (if (equal? #f (string->number originalNumber)) badInput) (if (equal? #f (string->number s_oldBase)) badInput) (if (equal? #f (string->number s_newBase)) badInput) (define oldBase (string->number s_oldBase)) (define newBase (string->number s_newBase)) (define outDecimal (convertIntoDecimal originalNumber oldBase)) (define result "") ; holds the new number (define remainder 0) ; remainder for each iteration (define whole 0) ; the whole number after dividing (define temp 0) (do() ((= outDecimal 0)) ; stop when the decimal value reaches 0 (set! whole (quotient outDecimal newBase)) ; calc the whole number (set! temp (* whole newBase)) (set! remainder (- outDecimal temp)) ; calc the remainder (set! result (appending result remainder)) ; append the result (set! outDecimal (+ whole 0)) ; set outDecimal = whole ) ; end of do (if (> 1 0) (string->number (list->string(reverse (string->list result))))) ) ;end of method This code won't work since it uses another method that I didn't attach to the post (but it's irrelevant to the problem . Please take a look at those three IF-s ... I want to return "ERROR" if the user put some incorrect value , for example (convert "23asb4" "b5" "9") Thanks

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