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  • eclipse - starting with android sdk

    - by dontHaveName
    I want start programming for android.. What I have: -Windows 7 -Eclipse Classic 4.2 -Downloaded all there required files - http://developer.android.com/sdk/installing/adding-packages.html -ADT Plugin I want install new ADT plugin.. at first I tried to download it from http://dl-ssl.google.com/android/eclipse, I add it, but if i selected it there is only "pending.." and nothing has load..(maybe internet connection?I have selected Native connection in preferences after pending it wrotes: Unable to connect to repository http://dl-ssl.google.com/android/eclipse/content.xml org.eclipse.equinox.p2.core.ProvidesException ) Thats why I download ADT plugin. So if I select downloaded ADT plugin - content of it load - developer tools and ndk plugin so I select all and click next. It loads and writes this: "Cannot complete the install because one or more required items could not be found. Software being installed: Android Development Tools 20.0.3.v201208082019-427395 (com.android.ide.eclipse.adt.feature.group 20.0.3.v201208082019-427395) Missing requirement: Android Development Tools 20.0.3.v201208082019-427395 (com.android.ide.eclipse.adt.feature.group 20.0.3.v201208082019-427395) requires 'org.eclipse.wst.sse.core 0.0.0' but it could not be found" requires 'org.eclipse.wst.sse.core 0.0.0 this problem is shown here: http://developer.android.com/resources/faq/troubleshooting.html#installeclipsecomponents but there is solution only for version 3.3 and 3.4 (I have 4.2) anyway but I tried it- I look for updates but nothing were found I really dont know where could be problem.. Thanks for any answer. (sorry for my english) I will send 1€ to somebody who can solve my problem ;) (I think all problems all for internet connection but I cant set it..)

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  • perl - converting a date into a string

    - by Jason
    I need to convert a date to a string, the date is entered as 07/04/2010 and should then read July 4th 2010. It should also be able to be entered using singe digits instead of double (7 instead of 07, and it needs to add the 20 to the year if the user enters only /10) This is what I have so far - #!/usr/bin/perl use CGI qw(:standard); use strict; #declare variables my ($date, $month, $day, $year); my @months = ("January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"); #assign input item to variable $date = param('Date'); #break date apart $date =~ /([0-9]{1,2})\/([0-9]{1,2})\/([0-9]{2,2}|20[0-9]{2,2})/; $month = $1; $day = $2; $year = $3; unless($year =~ /20[0-9]{2,2}/){ $year = "20".$year; } $date = $months[int($1)]." ".$day.", ".$year; #display date print "<HTML><HEAD><TITLE>The Date</TITLE></HEAD>\n"; print "<BODY>\n"; print "The date is: $date\n"; print "</BODY></HTML>\n"; However I keep getting errors Use of uninitialized value in pattern match (m//) at c08ex6.cgi line 14. Use of uninitialized value in pattern match (m//) at c08ex6.cgi line 18. Use of uninitialized value in concatenation (.) or string at c08ex6.cgi line 19. Use of uninitialized value in int at c08ex6.cgi line 21. Use of uninitialized value in concatenation (.) or string at c08ex6.cgi line 21.

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  • Assign different colors to individual array elements

    - by rk.
    Say I have the array, arr1. I want to print this array (i.e. just display the numbers) but, I want to color the numbers based on their values. If arr1[i]<15, green, if arr1[i]20, red, else orange. Something to this effect. var arr1 = [ 5,10,13,19,21,25,22,18,15,13,11,12,15,20,18,17,16,18,23,25,25,22,18,15,13,11,12,15,20,18]; Here is what I tried doing: for(var i=0; i<arr1.length;i++){ if(arr1[i]<15){ var temp = $(this).css("color","green"); $this.text(temp); } else if(arr1[i]>20){ var temp = $(this).css("color","red"); $this.text(temp); } else { var temp = $(this).css("color","orange"); $this.text(temp); } } I tried changing the css property of individual elements and them adding them to the div, but it did not work for me. Can someone suggest how should I go about doing this?

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  • How to exclude rows where matching join is in an SQL tree

    - by Greg K
    Sorry for the poor title, I couldn't think how to concisely describe this problem. I have a set of items that should have a 1-to-1 relationship with an attribute. I have a query to return those rows where the data is wrong and this relationship has been broken (1-to-many). I'm gathering these rows to fix them and restore this 1-to-1 relationship. This is a theoretical simplification of my actual problem but I'll post example table schema here as it was requested. item table: +------------+------------+-----------+ | item_id | name | attr_id | +------------+------------+-----------+ | 1 | BMW 320d | 20 | | 1 | BMW 320d | 21 | | 2 | BMW 335i | 23 | | 2 | BMW 335i | 34 | +------------+------------+-----------+ attribute table: +---------+-----------------+------------+ | attr_id | value | parent_id | +---------+-----------------+------------+ | 20 | SE | 21 | | 21 | M Sport | 0 | | 23 | AC | 24 | | 24 | Climate control | 0 | .... | 34 | Leather seats | 0 | +---------+-----------------+------------+ A simple query to return items with more than one attribute. SELECT item_id, COUNT(DISTINCT(attr_id)) AS attributes FROM item GROUP BY item_id HAVING attributes > 1 This gets me a result set like so: +-----------+------------+ | item_id | attributes | +-----------+------------+ | 1 | 2 | | 2 | 2 | | 3 | 2 | -- etc. -- However, there's an exception. The attribute table can hold a tree structure, via parent links in the table. For certain rows, parent_id can hold the ID of another attribute. There's only one level to this tree. Example: +---------+-----------------+------------+ | attr_id | value | parent_id | +---------+-----------------+------------+ | 20 | SE | 21 | | 21 | M Sport | 0 | .... I do not want to retrieve items in my original query where, for a pair of associated attributes, they related like attributes 20 & 21. I do want to retrieve items where: the attributes have no parent for two or more attributes they are not related (e.g. attributes 23 & 34) Example result desired, just the item ID: +------------+ | item_id | +------------+ | 2 | +------------+ How can I join against attributes from items and exclude these rows? Do I use a temporary table or can I achieve this from a single query? Thanks.

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  • How do I Order on common attribute of two models in the DB?

    - by Will
    If i have two tables Books, CDs with corresponding models. I want to display to the user a list of books and CDs. I also want to be able to sort this list on common attributes (release date, genre, price, etc.). I also have basic filtering on the common attributes. The list will be large so I will be using pagination in manage the load. items = [] items << CD.all(:limit => 20, :page => params[:page], :order => "genre ASC") items << Book.all(:limit => 20, :page => params[:page], :order => "genre ASC") re_sort(items,"genre ASC") Right now I am doing two queries concatenating them and then sorting them. This is very inefficient. Also this breaks down when I use paging and filtering. If I am on page 2 of how do I know what page of each table individual table I am really on? There is no way to determine this information without getting all items from each table. I have though that if I create a new Class called items that has a one to one relationship with either a Book or CD and do something like Item.all(:limit => 20, :page => params[:page], :include => [:books, :cds], :order => "genre ASC") However this gives back an ambiguous error. So can only be refined as Item.all(:limit => 20, :page => params[:page], :include => [:books, :cds], :order => "books.genre ASC") And does not interleave the books and CDs in a way that I want. Any suggestions.

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  • advanced select in Stored Procedure

    - by Auro
    Hey i got this Table: CREATE TABLE Test_Table ( old_val VARCHAR2(3), new_val VARCHAR2(3), Updflag NUMBER, WorkNo NUMBER ); and this is in my Table: INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('1',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 20',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('2',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('3',' 30',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); INSERT INTO Test_Table (old_val, new_val, Updflag , WorkNo) VALUES('4',' 40',0,0); now my Table Looks like this: Row Old_val New_val Updflag WorkNo 1 '1' ' 20' 0 0 2 '2' ' 20' 0 0 3 '2' ' 30' 0 0 4 '3' ' 30' 0 0 5 '4' ' 40' 0 0 6 '5' ' 40' 0 0 (if the value in the new_val column are same then they are together and the same goes to old_val) so in the example above row 1-4 are together and row 5-6 at the moment i have in my Stored Procedure a cursor: SELECT t1.Old_val, t1.New_val, t1.updflag, t1.WorkNo FROM Test_Table t1 WHERE t1.New_val = ( SELECT t2.New_val FROM Test_Table t2 WHERE t2.Updflag = 0 AND t2.Worknr = 0 AND ROWNUM = 1 ) the output is this: Row Old_val New_val Updflag WorkNo 1 1 20 0 0 2 2 20 0 0 my Problem is, i dont know how to get row 1 to 4 with one select. (i had an idea with 4 sub-querys but this wont work if its more data that matches together) does anyone of you have an idea?

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  • Update a portion UIView

    - by Brett
    Hi; I'm using -setNeedsDisplayinRect to update only a part of my UIView. However, all of my drawing done previously to calling this method is erased. Here is my code in the UIView subclass: -(void)drawRect:(CGRect)rect{ CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetRGBFillColor(context, r, g, b, 1); CGContextSetRGBStrokeColor(context, r, g, b, 1); CGRect arect = CGRectMake(x,y,1,1); CGContextFillRect(context, arect); NSLog(@"drawing"); } and in the view controller: -(void)drawView{ drawingView = [[DrawingView alloc]init]; x=10; y=10; r=0; g=0; b=0; [drawingView setNeedsDisplayInRect:CGRectMake(x, y, 1, 1)]; x=20; y=20; r=0; g=0; b=0; [drawingView setNeedsDisplayInRect:CGRectMake(x, y, 1, 1)]; } I end up with a screen where there is only one pixel at 20,20. Any help with this is so much appreciated. I am a beginner with XCode and am trying to complete a class project asap.

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  • algorithm to find longest non-overlapping sequences

    - by msalvadores
    I am trying to find the best way to solve the following problem. By best way I mean less complex. As an input a list of tuples (start,length) such: [(0,5),(0,1),(1,9),(5,5),(5,7),(10,1)] Each element represets a sequence by its start and length, for example (5,7) is equivalent to the sequence (5,6,7,8,9,10,11) - a list of 7 elements starting with 5. One can assume that the tuples are sorted by the start element. The output should return a non-overlapping combination of tuples that represent the longest continuos sequences(s). This means that, a solution is a subset of ranges with no overlaps and no gaps and is the longest possible - there could be more than one though. For example for the given input the solution is: [(0,5),(5,7)] equivalent to (0,1,2,3,4,5,6,7,8,9,10,11) is it backtracking the best approach to solve this problem ? I'm interested in any different approaches that people could suggest. Also if anyone knows a formal reference of this problem or another one that is similar I'd like to get references. BTW - this is not homework. Edit Just to avoid some mistakes this is another example of expected behaviour for an input like [(0,1),(1,7),(3,20),(8,5)] the right answer is [(3,20)] equivalent to (3,4,5,..,22) with length 20. Some of the answers received would give [(0,1),(1,7),(8,5)] equivalent to (0,1,2,...,11,12) as right answer. But this last answer is not correct because is shorter than [(3,20)].

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  • Best practice to hide/encrypt email adress in webpage

    - by Sebi
    I couldn't find a similar question, that's why here it is: Whats the best way to hide or encrypt an email link in a website, so that a crawler can't read it, but the user can nevertheless click it? I don't want to conufse the users by typing the email like this: john (at) mail.com or similar ways. (and i think this kind of links can nevertheless read by crawlers?) I also tried things like that: <script>// <![CDATA[eval(unescape('%76%61%72%20%73%3D%27%61%6D%6C%69%6F%74%72%3A%62%61%40%65%64%61%6E%6F%6C%2E%69%27%3B%76%61%72%20%72%3D%27%27%3B%66%6F%72%28%76%61%72%20%69%3D%30%3B%69%3C%73%2E%6C%65%6E%67%74%68%3B%69%2B%2B%2C%69%2B%2B%29%7B%72%3D%72%2B%73%2E%73%75%62%73%74%72%69%6E%67%28%69%2B%31%2C%69%2B%32%29%2B%73%2E%73%75%62%73%74%72%69%6E%67%28%69%2C%69%2B%31%29%7D%64%6F%63%75%6D%65%6E%74%2E%77%72%69%74%65%28%27%3C%61%20%68%72%65%66%3D%22%27%2B%72%2B%27%22%3E%4F%62%65%72%70%61%72%6C%65%69%74%65%72%3C%2F%61%3E%27%29%3B'))]]></script> but i heard this can also be read by crawler and it isn't really good practices are ther any common approaches?

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  • Why might this work on my server but not my schools?

    - by Doug
    I created a captcha just now, and it works PERFECTLY on my own server. On the school's server, it doesn't generate an image. Why might this be? The difference in code is one line. *Edit:*Originally, it was working, but I deleted the directory by mistake and I do not know why did it suddenly work in the first place. Source code on school server: <?php session_save_path("/ichanged/this/path/for/this/post/"); session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?> Source code on my server: <?php session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?>

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  • Function to even out multiple arrays

    - by Moak
    Assume I have a function evenOut($array, $limit){ //returns exactly $limit items } and this data $animals = array(); $animals['barn'] = array_fill(0,20, 'b'); $animals['forest'] = array_fill(0,20, 'f'); $animals['house'] = array_fill(0,20, 'h'); $animals['mountain'] = array_fill(0,20, 'm'); I want to return a maximum of 10 animals, however they should be spread out evenly among the locations they come from. so if i did evenOut($animals,8); i'd get 2 of each('b','b','f','f','h','h','m','m',) evenOut($animals,2); should return ('b','f') if I have this data $animals = array(); $animals['barn'] = array_fill(0,1, 'b'); $animals['forest'] = array_fill(0,3, 'f'); $animals['house'] = array_fill(0,8, 'h'); $animals['mountain'] = array_fill(0,1, 'm'); evenOut($animals,8); expected result would be ('b','f','f','f','h','h','h','m',) evenOut($animals,10); expected result would be ('b','f','f','f','h','h','h','h','h','m',) $animals = array(); $animals['barn'] = array_fill(0,0, 'b'); $animals['forest'] = array_fill(0,3, 'f'); evenOut($animals,10); expected result would be ('f','f','f') I'm not sure how I should approach this, I am hoping there is a simple way

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  • Read char from txt file in C++

    - by Jack in the Box
    I have a program that will read the number of rows and columns from a txt file. Also, the program has to read the contents of a 2D array from the same file. Here is the txt file 8 20 * * *** *** 8 and 20 are the number of rows and columns respectively. The spaces and asterisks are the contents of the array, Array[8][20] For example, Array[0][1] = '*' I did make the program reading 8 and 20 as follow: ifstream myFile; myFile.open("life.txt"); if(!myFile) { cout << endl << "Failed to open file"; return 1; } myFile >> rows >> cols; myFile.close(); grid = new char*[rows]; for (int i = 0; i < rows; i++) { grid[i] = new char[cols]; } Now, how to assign the spaces and the asterisks to to the fields in the array? I hope you got the point.

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  • Action listener for JButton array

    - by user530809
    Let's say I have a program with 2D array of buttons, and when you click one of them it turns red. I didn't want to declare every single button seperately so I just created JButton[][] array for them. The problem is that I don't know how to use action listener on any of the buttons in the array so it would change the color of this particular button, and none of related questions is relevant to this. I tried to use "for" but it doesn't help: package appli; import javax.swing.*; import java.awt.*; import java.awt.event.*; public class MainW extends JFrame implements ActionListener { public MainW(){ setSize(640,480); setTitle("title"); setLayout(null); JButton[][] btnz = new JButton[5][5]; for(Integer i=0;i<5;i++) { for(Integer j=0;j<5;j++) { btnz[i][j]= new JButton(""); btnz[i][j].setBackground(Color.WHITE); btnz[i][j].setBounds(10+20*i,10+20*j,20,20); add(btnz[i][j]); btnz[i][j].addActionListener(this); } } setDefaultCloseOperation(EXIT_ON_CLOSE); setVisible(true); } public void actionPerformed(ActionEvent e){ for(Integer i=0;i<5;i++) { for(Integer j=0;j<5;j++) { if (e.getSource()==btnz[i][j]); { btnz[i][j].setBackground(Color.RED); } } } } }

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  • Why does my perl script return a zero return code when I explicitly call exit with a non-zero parame

    - by Tom Duckering
    I have a perl script which calls another script. The perl script should be propagating the script's return code but seems to be returning zero to its caller (a Java application) desipte the explicit call to exit $scriptReturnCode. It's probably something dumb since I'm by no means a perl expert. Code and output as follows (I realise that <=> could/should be != but that's what I have): print "INFO: Calling ${scriptDirectory}/${script} ${args}" $scriptReturnCode = system("${scriptDirectory}/${script} ${args}"); if ( $scriptReturnCode <=> 0 ) { print "ERROR: The script returned $scriptReturnCode\n"; exit $scriptReturnCode; } else { print "INFO: The script returned $scriptReturnCode.\n"; exit 0; } The output I have from my Java is: 20/04/2010 14:40:01 - INFO: Calling /path/to/script/script.ksh arg1 arg2 20/04/2010 14:40:01 - Could not find installer files <= this is from the script.ksh 20/04/2010 14:40:01 - ERROR: The script returned 256 20/04/2010 14:40:01 - Command Finished. Exit Code: 0 <= this is the Java app.

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  • C read X bytes from a file, padding if needed

    - by Hunter McMillen
    I am trying to read in an input file 64 bits at a time, then do some calculations on those 64 bits, the problem is I need to convert the ascii text to hexadecimal characters. I have searched around but none of the answers posted seem to work for my situation. Here is what I have: int main(int argc, int * argv) { char buffer[9]; FILE *f; unsigned long long test; if(f = fopen("input2.txt", "r")) { while( fread(buffer, 8, 1, f) != 0) //while not EOF read 8 bytes at a time { buffer[8] = '\0'; test = strtoull(buffer, NULL, 16); //interpret as hex printf("%llu\n", test); printf("%s\n", buffer); } fclose(f); } } For an input like this: "testing string to hex conversion" I get results like this: 0 testing 0 string t 0 o hex co 0 nversion Where I would expect: 74 65 73 74 69 6e 67 20 <- "testing" in hex testing 73 74 72 69 6e 67 20 74 <- "string t" in hex string t 6f 20 68 65 78 20 63 6f <- "o hex co" in hex o hex co 6e 76 65 72 73 69 6f 6e <- "nversion" in hex nversion Can anyone see where I misstepped?

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  • swap! alter and alike

    - by mekka
    Hello, I am having a problem understanding how these functions update the underlying ref, atom etc. The docs say: (apply f current-value-of-identity args) (def one (atom 0)) (swap! one inc) ;; => 1 So I am wondering how it got "expanded" to the apply form. It's not mentioned what exactly 'args' in the apply form is. Is it a sequence of arguments or are these separate values? Was it "expanded" to: (apply inc 0) ; obviously this wouldnt work, so that leaves only one possibility (apply inc 0 '()) (swap! one + 1 2 3) ;; #=> 7 Was it: (apply + 1 1 2 3 '()) ;or (apply + 1 [1 2 3]) (def two (atom [])) (swap! two conj 10 20) ;; #=> [10 20] Was it: (apply conj [] [10 20]) ;or (apply conj [] 10 20 '()) If I swap with a custom function like this: (def three (atom 0)) (swap! three (fn [current elem] (println (class elem))) 10) ;;#=> java.Lang.Integer Which means that the value '10' doesnt magically get changed into a seq '(10) and leads me to the conclusion, that it gets "expanded" to: (apply f current-value-of-identity arg1 arg2 arg3... '()) Is that a correct assumption and the docs are simply lacking a better description?

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  • How To Delete objet whit mouse click ?

    - by Meko
    Hi all. I made a simple FlowChat Editor that creates rectangles and triangles and connect them each other and shows the way from up to down. I can move this elements on screen to .But I am tying to create button to delete element which I clicked. There is problem that I can delete mytriangle object but but I cant delete myRectangle objects.It deletes but not object which i clicked.I delete from first object to last ..Here my code ... if (deleteObj) { if (rectsList.size() != 0) { for (int i = 0; i < rectsList.size(); i++) { MyRect rect = (MyRect) rectsList.get(i); if (e.getX() <= rect.c.x + 50 && e.getX() >= rect.c.x - 50 && e.getY() <= rect.c.y + 15 && e.getY() >= rect.c.y - 15) { rectsList.remove(rect); System.out.println("This is REctangle DELETED\n"); } } } if (triangleList.size() != 0) { for (int j = 0; j < triangleList.size(); j++) { MyTriangle trian = (MyTriangle) triangleList.get(j); if (e.getX() <= trian.c.x + 20 && e.getX() >= trian.c.x - 20 && e.getY() <= trian.c.y + 20 && e.getY() >= trian.c.y - 20) { triangleList.remove(trian); System.out.println("This is Triangle Deleted\n"); } } }

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  • CoffeeScript 2 Dimensional Array Usage

    - by Chris
    I feel like I'm missing something with CoffeeScript and 2 dimensional arrays. I'm simply attempting to make a grid of spaces (think checkers). After some searching and a discovery with the arrays.map function, I came up with this: @spaces = [0...20].map (x)-> [0...20].map (y) -> new Elements.Space() And this seems to work great, I have a nice 2 dimensional array with my Space object created in each. But now I want to send the created space constructor the x,y location. Because I'm two layers deep, I lost the x variable when I entered the map function for y. Ideally I would want to do something like: @spaces = [0...20].map (x)-> [0...20].map (y) -> new Elements.Space(x, y) or something that feels more natural to me like: for row in rows for column in row @spaces[row][column] = new Elements.Space(row, column) I'm really open to any better way of doing this. I know how I would do it in standard JavaScript, but really would like to learn how to do it in CoffeeScript.

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  • ???Flashback Log???????Redo Log?

    - by Liu Maclean(???)
    ????????????????????redo log?   RVWR( Recovery Writer)?3s??flashback generate buffer??block before image?????????? ?????block change???RVWR??block before image ?flashback log? ?????????,Oracle???????????before image????????,????????flashback database logs?????   ???????????,????? ??????????????????,???????????before image?????shared pool??flashback log buffer?,RVWR??????flashback log buffer??????????? ?DBWR???????????????,DBWR?????buffer header??FBA(Flashback Byte Address)?flashback log buffer?????????? ???? ?????? ??? ????????????? , RVWR???????????(flashback markers)?flashback database logs?? ????(flashback markers)?????????????Oracle??flashback ??????????  ??????????, Oracle ??????(flashback markers)????????????flashback database log???????????block image; ??Oracle ???????(forward recovery)?????????????????SCN?????? flashback markers for example: **** Record at fba: (lno 1 thr 1 seq 1 bno 4 bof 8184) **** RECORD HEADER: Type: 3 (Skip) Size: 8132 RECORD DATA (Skip): **** Record at fba: (lno 1 thr 1 seq 1 bno 4 bof 52) **** RECORD HEADER: Type: 7 (Begin Crash Recovery Record) Size: 36 RECORD DATA (Begin Crash Recovery Record): Previous logical record fba: (lno 1 thr 1 seq 1 bno 3 bof 316) Record scn: 0x0000.00000000 [0.0] **** Record at fba: (lno 1 thr 1 seq 1 bno 3 bof 8184) **** RECORD HEADER: Type: 3 (Skip) Size: 7868 RECORD DATA (Skip): **** Record at fba: (lno 1 thr 1 seq 1 bno 3 bof 316) **** RECORD HEADER: Type: 2 (Marker) Size: 300 RECORD DATA (Marker): Previous logical record fba: (lno 0 thr 0 seq 0 bno 0 bof 0) Record scn: 0x0000.00000000 [0.0] Marker scn: 0x0000.0060e024 [0.6348836] 06/13/2012 15:56:35 Flag 0x0 Flashback threads: 1, Enabled redo threads 1 Recovery Start Checkpoint: scn: 0x0000.0060e024 [0.6348836] 06/13/2012 15:56:12 thread:1 rba:(0x80.180.10) Flashback thread Markers: Thread:1 status:0 fba: (lno 1 thr 1 seq 1 bno 2 bof 8184) Redo Thread Checkpoint Info: Thread:1 rba:(0x80.180.10) **** Record at fba: (lno 1 thr 1 seq 1 bno 2 bof 8184) **** RECORD HEADER: Type: 3 (Skip) Size: 8168 RECORD DATA (Skip): End-Of-Thread reached ????????????????block change ????before image????????flashback log?? ?????block change???flashback log record ????????? redo log???!????flashback log ???????before image ? redo log??? change vector ?  Oracle?????????????????????????????????????,??????I/O??????????????: ??hot block??,Oracle???????????block image?????; Oracle ?????????(flashback barriers)???????????????,flashback barriers???????(???15??),??????????(flashback barriers)????(flashback markers)????????? ????, ??????change?????, ???????????????????????????, ?15????????????????????flashback log????????before image?????????????,?????????????????????,?????????????? ????????,??????????????(flashback barriers), flashback barriers???????,?????15????? ?????flashback barriers????????(flashback markers)???????????????,???????????????????(????barriers?????)??????block image ,????????????????????????????????? ??????????flashback log????redo log????! ????,????????????????, ?????????? SQL> select * from v$version; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production PL/SQL Release 11.2.0.3.0 - Production CORE 11.2.0.3.0 Production TNS for Linux: Version 11.2.0.3.0 - Production NLSRTL Version 11.2.0.3.0 - Production SQL> select * from global_name; GLOBAL_NAME -------------------------------------------------------------------------------- www.oracledatabase12g.com SQL> create table flash_maclean (t1 varchar2(200)) tablespace users; Table created. SQL> insert into flash_maclean values('MACLEAN LOVE HANNA'); 1 row created. SQL> commit; Commit complete. SQL> startup force; ORACLE instance started. Total System Global Area 939495424 bytes Fixed Size 2233960 bytes Variable Size 713034136 bytes Database Buffers 218103808 bytes Redo Buffers 6123520 bytes Database mounted. Database opened. SQL> update flash_maclean set t1='HANNA LOVE MACLEAN'; 1 row updated. commit; Commit complete. SQL> alter system checkpoint; System altered. SQL> select dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_relative_fno(rowid) from flash_maclean; DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID) DBMS_ROWID.ROWID_RELATIVE_FNO(ROWID) ------------------------------------ ------------------------------------ 140431 4 datafile 4 block 140431 ??RDBA rdba: 0x0102248f (4/140431) SQL> ! ps -ef|grep rvwr|grep -v grep oracle 26695 1 0 15:56 ? 00:00:00 ora_rvwr_G11R23 SQL> oradebug setospid 26695 Oracle pid: 20, Unix process pid: 26695, image: [email protected] (RVWR) SQL> ORADEBUG DUMP FBTAIL 1; Statement processed. To dump the last 2000 flashback records , ??ORADEBUG DUMP FBTAIL 1????????2000?????? SQL> oradebug tracefile_name /s01/orabase/diag/rdbms/g11r23/G11R23/trace/G11R23_rvwr_26695.trc ? TRACE?????????block? before image **** Record at fba: (lno 1 thr 1 seq 1 bno 55 bof 2564) **** RECORD HEADER: Type: 1 (Block Image) Size: 28 RECORD DATA (Block Image): file#: 4 rdba: 0x0102248f Next scn: 0x0000.00000000 [0.0] Flag: 0x0 Block Size: 8192 BLOCK IMAGE: buffer rdba: 0x0102248f scn: 0x0000.00609044 seq: 0x01 flg: 0x06 tail: 0x90440601 frmt: 0x02 chkval: 0xc626 type: 0x06=trans data Hex dump of block: st=0, typ_found=1 Dump of memory from 0x00002B1D94183C00 to 0x00002B1D94185C00 2B1D94183C00 0000A206 0102248F 00609044 06010000 [.....$..D.`.....] 2B1D94183C10 0000C626 00000001 00014AD4 0060903A [&........J..:.`.] 2B1D94183C20 00000000 00320002 01022488 00090006 [......2..$......] 2B1D94183C30 00000CC8 00C00340 000D0542 00008000 [[email protected].......] 2B1D94183C40 006040BC 000F000A 00000920 00C002E4 [.@`..... .......] 2B1D94183C50 0017048F 00002001 00609044 00000000 [..... ..D.`.....] 2B1D94183C60 00000000 00010100 0014FFFF 1F6E1F77 [............w.n.] 2B1D94183C70 00001F6E 1F770001 00000000 00000000 [n.....w.........] 2B1D94183C80 00000000 00000000 00000000 00000000 [................] Repeat 500 times 2B1D94185BD0 00000000 00000000 2C000000 4D120102 [...........,...M] 2B1D94185BE0 454C4341 4C204E41 2045564F 4E4E4148 [ACLEAN LOVE HANN] 2B1D94185BF0 01002C41 43414D07 4E41454C 90440601 [A,...MACLEAN..D.] Block header dump: 0x0102248f Object id on Block? Y seg/obj: 0x14ad4 csc: 0x00.60903a itc: 2 flg: E typ: 1 - DATA brn: 0 bdba: 0x1022488 ver: 0x01 opc: 0 inc: 0 exflg: 0 Itl Xid Uba Flag Lck Scn/Fsc 0x01 0x0006.009.00000cc8 0x00c00340.0542.0d C--- 0 scn 0x0000.006040bc 0x02 0x000a.00f.00000920 0x00c002e4.048f.17 --U- 1 fsc 0x0000.00609044 bdba: 0x0102248f data_block_dump,data header at 0x2b1d94183c64 =============== tsiz: 0x1f98 hsiz: 0x14 pbl: 0x2b1d94183c64 76543210 flag=-------- ntab=1 nrow=1 frre=-1 fsbo=0x14 fseo=0x1f77 avsp=0x1f6e tosp=0x1f6e 0xe:pti[0] nrow=1 offs=0 0x12:pri[0] offs=0x1f77 block_row_dump: tab 0, row 0, @0x1f77 tl: 22 fb: --H-FL-- lb: 0x2 cc: 1 col 0: [18] 4d 41 43 4c 45 41 4e 20 4c 4f 56 45 20 48 41 4e 4e 41 end_of_block_dump SQL> select dump('MACLEAN LOVE HANNA',16) from dual; DUMP('MACLEANLOVEHANNA',16) -------------------------------------------------------------------- Typ=96 Len=18: 4d,41,43,4c,45,41,4e,20,4c,4f,56,45,20,48,41,4e,4e,41 ???????????????????????,??flashback log??before image????????? create table flash_maclean1 (t1 int) tablespace users; SQL> select vs.name, ms.value 2 from v$mystat ms, v$sysstat vs 3 where vs.statistic# = ms.statistic# 4 and vs.name in ('redo size','db block changes'); NAME VALUE ---------------------------------------------------------------- ---------- db block changes 0 redo size 0 SQL> select name,value from v$sysstat where name like 'flashback log%'; NAME VALUE ---------------------------------------------------------------- ---------- flashback log writes 49 flashback log write bytes 9306112 SQL> begin 2 for i in 1..5000 loop 3 update flash_maclean1 set t1=t1+1; 4 commit; 5 end loop; 6 end; 7 / PL/SQL procedure successfully completed. SQL> select vs.name, ms.value 2 from v$mystat ms, v$sysstat vs 3 where vs.statistic# = ms.statistic# 4 and vs.name in ('redo size','db block changes'); NAME VALUE ---------------------------------------------------------------- ---------- db block changes 20006 redo size 3071288 SQL> select name,value from v$sysstat where name like 'flashback log%'; NAME VALUE ---------------------------------------------------------------- ---------- flashback log writes 52 flashback log write bytes 10338304 ??????????? ??hot block,???20006 ?block changes???? ??? 3000k ?redo log ? ??1000k? flashback log ?

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  • So…is it a Seek or a Scan?

    - by Paul White
    You’re probably most familiar with the terms ‘Seek’ and ‘Scan’ from the graphical plans produced by SQL Server Management Studio (SSMS).  The image to the left shows the most common ones, with the three types of scan at the top, followed by four types of seek.  You might look to the SSMS tool-tip descriptions to explain the differences between them: Not hugely helpful are they?  Both mention scans and ranges (nothing about seeks) and the Index Seek description implies that it will not scan the index entirely (which isn’t necessarily true). Recall also yesterday’s post where we saw two Clustered Index Seek operations doing very different things.  The first Seek performed 63 single-row seeking operations; and the second performed a ‘Range Scan’ (more on those later in this post).  I hope you agree that those were two very different operations, and perhaps you are wondering why there aren’t different graphical plan icons for Range Scans and Seeks?  I have often wondered about that, and the first person to mention it after yesterday’s post was Erin Stellato (twitter | blog): Before we go on to make sense of all this, let’s look at another example of how SQL Server confusingly mixes the terms ‘Scan’ and ‘Seek’ in different contexts.  The diagram below shows a very simple heap table with two columns, one of which is the non-clustered Primary Key, and the other has a non-unique non-clustered index defined on it.  The right hand side of the diagram shows a simple query, it’s associated query plan, and a couple of extracts from the SSMS tool-tip and Properties windows. Notice the ‘scan direction’ entry in the Properties window snippet.  Is this a seek or a scan?  The different references to Scans and Seeks are even more pronounced in the XML plan output that the graphical plan is based on.  This fragment is what lies behind the single Index Seek icon shown above: You’ll find the same confusing references to Seeks and Scans throughout the product and its documentation. Making Sense of Seeks Let’s forget all about scans for a moment, and think purely about seeks.  Loosely speaking, a seek is the process of navigating an index B-tree to find a particular index record, most often at the leaf level.  A seek starts at the root and navigates down through the levels of the index to find the point of interest: Singleton Lookups The simplest sort of seek predicate performs this traversal to find (at most) a single record.  This is the case when we search for a single value using a unique index and an equality predicate.  It should be readily apparent that this type of search will either find one record, or none at all.  This operation is known as a singleton lookup.  Given the example table from before, the following query is an example of a singleton lookup seek: Sadly, there’s nothing in the graphical plan or XML output to show that this is a singleton lookup – you have to infer it from the fact that this is a single-value equality seek on a unique index.  The other common examples of a singleton lookup are bookmark lookups – both the RID and Key Lookup forms are singleton lookups (an RID lookup finds a single record in a heap from the unique row locator, and a Key Lookup does much the same thing on a clustered table).  If you happen to run your query with STATISTICS IO ON, you will notice that ‘Scan Count’ is always zero for a singleton lookup. Range Scans The other type of seek predicate is a ‘seek plus range scan’, which I will refer to simply as a range scan.  The seek operation makes an initial descent into the index structure to find the first leaf row that qualifies, and then performs a range scan (either backwards or forwards in the index) until it reaches the end of the scan range. The ability of a range scan to proceed in either direction comes about because index pages at the same level are connected by a doubly-linked list – each page has a pointer to the previous page (in logical key order) as well as a pointer to the following page.  The doubly-linked list is represented by the green and red dotted arrows in the index diagram presented earlier.  One subtle (but important) point is that the notion of a ‘forward’ or ‘backward’ scan applies to the logical key order defined when the index was built.  In the present case, the non-clustered primary key index was created as follows: CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col ASC) ) ; Notice that the primary key index specifies an ascending sort order for the single key column.  This means that a forward scan of the index will retrieve keys in ascending order, while a backward scan would retrieve keys in descending key order.  If the index had been created instead on key_col DESC, a forward scan would retrieve keys in descending order, and a backward scan would return keys in ascending order. A range scan seek predicate may have a Start condition, an End condition, or both.  Where one is missing, the scan starts (or ends) at one extreme end of the index, depending on the scan direction.  Some examples might help clarify that: the following diagram shows four queries, each of which performs a single seek against a column holding every integer from 1 to 100 inclusive.  The results from each query are shown in the blue columns, and relevant attributes from the Properties window appear on the right: Query 1 specifies that all key_col values less than 5 should be returned in ascending order.  The query plan achieves this by seeking to the start of the index leaf (there is no explicit starting value) and scanning forward until the End condition (key_col < 5) is no longer satisfied (SQL Server knows it can stop looking as soon as it finds a key_col value that isn’t less than 5 because all later index entries are guaranteed to sort higher). Query 2 asks for key_col values greater than 95, in descending order.  SQL Server returns these results by seeking to the end of the index, and scanning backwards (in descending key order) until it comes across a row that isn’t greater than 95.  Sharp-eyed readers may notice that the end-of-scan condition is shown as a Start range value.  This is a bug in the XML show plan which bubbles up to the Properties window – when a backward scan is performed, the roles of the Start and End values are reversed, but the plan does not reflect that.  Oh well. Query 3 looks for key_col values that are greater than or equal to 10, and less than 15, in ascending order.  This time, SQL Server seeks to the first index record that matches the Start condition (key_col >= 10) and then scans forward through the leaf pages until the End condition (key_col < 15) is no longer met. Query 4 performs much the same sort of operation as Query 3, but requests the output in descending order.  Again, we have to mentally reverse the Start and End conditions because of the bug, but otherwise the process is the same as always: SQL Server finds the highest-sorting record that meets the condition ‘key_col < 25’ and scans backward until ‘key_col >= 20’ is no longer true. One final point to note: seek operations always have the Ordered: True attribute.  This means that the operator always produces rows in a sorted order, either ascending or descending depending on how the index was defined, and whether the scan part of the operation is forward or backward.  You cannot rely on this sort order in your queries of course (you must always specify an ORDER BY clause if order is important) but SQL Server can make use of the sort order internally.  In the four queries above, the query optimizer was able to avoid an explicit Sort operator to honour the ORDER BY clause, for example. Multiple Seek Predicates As we saw yesterday, a single index seek plan operator can contain one or more seek predicates.  These seek predicates can either be all singleton seeks or all range scans – SQL Server does not mix them.  For example, you might expect the following query to contain two seek predicates, a singleton seek to find the single record in the unique index where key_col = 10, and a range scan to find the key_col values between 15 and 20: SELECT key_col FROM dbo.Example WHERE key_col = 10 OR key_col BETWEEN 15 AND 20 ORDER BY key_col ASC ; In fact, SQL Server transforms the singleton seek (key_col = 10) to the equivalent range scan, Start:[key_col >= 10], End:[key_col <= 10].  This allows both range scans to be evaluated by a single seek operator.  To be clear, this query results in two range scans: one from 10 to 10, and one from 15 to 20. Final Thoughts That’s it for today – tomorrow we’ll look at monitoring singleton lookups and range scans, and I’ll show you a seek on a heap table. Yes, a seek.  On a heap.  Not an index! If you would like to run the queries in this post for yourself, there’s a script below.  Thanks for reading! IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; -- ================ -- Singleton lookup -- ================ ; -- Single value equality seek in a unique index -- Scan count = 0 when STATISTIS IO is ON -- Check the XML SHOWPLAN SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 32 ; -- =========== -- Range Scans -- =========== ; -- Query 1 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col <= 5 ORDER BY E.key_col ASC ; -- Query 2 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col > 95 ORDER BY E.key_col DESC ; -- Query 3 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 10 AND E.key_col < 15 ORDER BY E.key_col ASC ; -- Query 4 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 20 AND E.key_col < 25 ORDER BY E.key_col DESC ; -- Final query (singleton + range = 2 range scans) SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 10 OR E.key_col BETWEEN 15 AND 20 ORDER BY E.key_col ASC ; -- === TIDY UP === DROP TABLE dbo.Example; © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

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  • problem in login in yahoo massanger

    - by khoyendra
    package session; import java.io.FileWriter; import java.text.DateFormat; import java.text.SimpleDateFormat; import javax.swing.JOptionPane; import org.openymsg.network.FireEvent; import org.openymsg.network.Session; import org.openymsg.network.SessionState; import org.openymsg.network.event.SessionListener; public class BotGUI extends javax.swing.JFrame implements SessionListener{ /** Creates new form BotGUI */ FileWriter fw; DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss"); public BotGUI() { initComponents(); } @SuppressWarnings("unchecked") // <editor-fold defaultstate="collapsed" desc="Generated Code"> private void initComponents() { jPanel1 = new javax.swing.JPanel(); jPanel2 = new javax.swing.JPanel(); jPanel3 = new javax.swing.JPanel(); jLabel1 = new javax.swing.JLabel(); jPanel4 = new javax.swing.JPanel(); jLabel2 = new javax.swing.JLabel(); jLabel3 = new javax.swing.JLabel(); uNameTextField = new javax.swing.JTextField(); uPassPasswordField = new javax.swing.JPasswordField(); jButton1 = new javax.swing.JButton(); jMenuBar1 = new javax.swing.JMenuBar(); jMenu1 = new javax.swing.JMenu(); jMenuItem1 = new javax.swing.JMenuItem(); jMenuItem2 = new javax.swing.JMenuItem(); jMenuItem3 = new javax.swing.JMenuItem(); jMenu2 = new javax.swing.JMenu(); setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); jPanel2.setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout()); jPanel3.setBackground(new java.awt.Color(51, 51, 51)); jLabel1.setBackground(new java.awt.Color(0, 0, 255)); jLabel1.setFont(new java.awt.Font("Tahoma", 1, 12)); jLabel1.setForeground(new java.awt.Color(255, 255, 255)); jLabel1.setText("Yahoo Login Panel"); javax.swing.GroupLayout jPanel3Layout = new javax.swing.GroupLayout(jPanel3); jPanel3.setLayout(jPanel3Layout); jPanel3Layout.setHorizontalGroup( jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel3Layout.createSequentialGroup() .addGap(38, 38, 38) .addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 140, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(532, Short.MAX_VALUE)) ); jPanel3Layout.setVerticalGroup( jPanel3Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jLabel1, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 30, Short.MAX_VALUE) ); jPanel2.add(jPanel3, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 0, 710, 30)); jPanel4.setLayout(new org.netbeans.lib.awtextra.AbsoluteLayout()); jLabel2.setText("Username"); jPanel4.add(jLabel2, new org.netbeans.lib.awtextra.AbsoluteConstraints(30, 20, 60, 20)); jLabel3.setText("Password"); jPanel4.add(jLabel3, new org.netbeans.lib.awtextra.AbsoluteConstraints(270, 20, 60, 20)); jPanel4.add(uNameTextField, new org.netbeans.lib.awtextra.AbsoluteConstraints(100, 20, 140, 20)); jPanel4.add(uPassPasswordField, new org.netbeans.lib.awtextra.AbsoluteConstraints(330, 20, 140, -1)); jButton1.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N jButton1.setText("Login"); jButton1.addActionListener(new java.awt.event.ActionListener() { public void actionPerformed(java.awt.event.ActionEvent evt) { jButton1ActionPerformed(evt); } }); jPanel4.add(jButton1, new org.netbeans.lib.awtextra.AbsoluteConstraints(490, 15, 90, -1)); jPanel2.add(jPanel4, new org.netbeans.lib.awtextra.AbsoluteConstraints(0, 30, 710, 60)); javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1); jPanel1.setLayout(jPanel1Layout); jPanel1Layout.setHorizontalGroup( jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel2, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); jPanel1Layout.setVerticalGroup( jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addGroup(jPanel1Layout.createSequentialGroup() .addComponent(jPanel2, javax.swing.GroupLayout.PREFERRED_SIZE, 135, javax.swing.GroupLayout.PREFERRED_SIZE) .addContainerGap(293, Short.MAX_VALUE)) ); jMenu1.setText("Option"); jMenuItem1.setText("Logout"); jMenu1.add(jMenuItem1); jMenuItem2.setText("Load CSV"); jMenu1.add(jMenuItem2); jMenuItem3.setText("Exit"); jMenu1.add(jMenuItem3); jMenuBar1.add(jMenu1); jMenu2.setText("Help"); jMenuBar1.add(jMenu2); setJMenuBar(jMenuBar1); javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); getContentPane().setLayout(layout); layout.setHorizontalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); layout.setVerticalGroup( layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) .addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE) ); pack(); }// </editor-fold> public void handleConnectionClosed() { connectionClosed = true; loggedIn = false; } private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) { if(!uNameTextField.getText().equals("") && !uPassPasswordField.getText().equals("")){ Yahoo_login(uNameTextField.getText(),uPassPasswordField.getText()); }else{ JOptionPane.showMessageDialog(null, "Plese Enter User Id and Password"); } } Session yahooMessengerSession; MySessionListener mySessionListener; boolean loggedIn = false; boolean connectionClosed = false; public void Yahoo_login(String uName, String pass) { connectionClosed = false; if (loggedIn == false) { yahooMessengerSession = new Session(); mySessionListener = new MySessionListener(this); yahooMessengerSession.addSessionListener(mySessionListener); try { if ((uName.equals("")) || (pass.equals(""))) { System.out.println("User name/password is blank"); } else{ //initialized a file writer for log file System.out.println("Login start........"); yahooMessengerSession.login(uName, pass, true); //checks whether user was succesful in login in if (yahooMessengerSession!=null && yahooMessengerSession.getSessionStatus()== SessionState.LOGGED_ON) { //this loop is reached when the user has been successfully logined System.out.println("Login Success"); fw.write("User (" + uName + ") logged in at : " + dateFormat.format("09.05.10") + " \n"); fw.close(); } else { yahooMessengerSession.reset(); } } } catch(Exception e){ } } } public static void main(String args[]) { java.awt.EventQueue.invokeLater(new Runnable() { public void run() { new BotGUI().setVisible(true); } }); } // Variables declaration - do not modify private javax.swing.JButton jButton1; private javax.swing.JLabel jLabel1; private javax.swing.JLabel jLabel2; private javax.swing.JLabel jLabel3; private javax.swing.JMenu jMenu1; private javax.swing.JMenu jMenu2; private javax.swing.JMenuBar jMenuBar1; private javax.swing.JMenuItem jMenuItem1; private javax.swing.JMenuItem jMenuItem2; private javax.swing.JMenuItem jMenuItem3; private javax.swing.JPanel jPanel1; private javax.swing.JPanel jPanel2; private javax.swing.JPanel jPanel3; private javax.swing.JPanel jPanel4; private javax.swing.JTextField uNameTextField; private javax.swing.JPasswordField uPassPasswordField; // End of variables declaration public void dispatch(FireEvent fe) { throw new UnsupportedOperationException("Not supported yet."); } } i have to find the error SEVERE: error during the dispatch of event: FireEvent [org.openymsg.network.event.SessionListEvent to:null from:null message:null timestamp:0 status:0 list type:Friends size:2 LIST] java.lang.UnsupportedOperationException: Not supported yet. at yahoomessangerbot.MySessionListener.dispatch(MySessionListener.java:131) at org.openymsg.network.EventDispatcher.runEventNOW(EventDispatcher.java:133) at org.openymsg.network.EventDispatcher.run(EventDispatcher.java:114)

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  • PE Header Requirements

    - by Pindatjuh
    What are the requirements of a PE file (PE/COFF)? What fields should be set, which value, at a bare minimum for enabling it to "run" on Windows (i.e. executing "ret" instruction and then close, without error). The library I am building first is the linker: Now, the problem I have is the PE file (PE/COFF). I don't know what is "required" for a PE file before it can actually execute on my platform. My testing platform is Vista. I get an error message, saying "This is not a valid Win32 executable." when I execute it by double-clicking, and I get an "Access Denied." when executing it with CLI cmd. I have two sections, .text and .data. I've implemented the PE headers as provided by several online documents, i.e. MSDN and some other thirdparty documentation. If I use a hex-editor, it looks almost like a regular PE file. I don't use any imports, nor IAT, nor any directories in the PE header. Edit: I've added an import table, still not a valid .exe-file, says my Windows. I've tried to use values which are also mentioned at the smallest PE-file guide. No luck. Really the only thing I can't seem to figure out is what is required and what isn't. Some guides tell me everything is required, whilst others say about deprications: and it can be zero. I hope this is enough information. Thank you, in advance. Raw data (as requested) of current PE header: 4D 5A 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 40 00 00 00 50 45 00 00 4C 01 02 00 C8 7A 55 4B 00 00 00 00 00 00 00 00 E0 00 82 01 0B 01 0D 25 00 10 00 00 00 10 00 00 00 00 00 00 00 10 00 00 00 10 00 00 00 20 00 00 00 00 40 00 00 10 00 00 00 02 00 00 01 00 0B 00 00 00 00 00 03 00 0A 00 00 00 00 00 00 22 00 00 38 01 00 00 00 00 00 00 03 00 00 00 00 40 00 00 00 40 00 00 00 40 00 00 00 40 00 00 00 00 00 00 0E 00 00 00 00 00 00 00 00 00 00 00 00 20 00 00 24 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 2E 74 65 78 74 00 00 00 00 00 00 00 00 10 00 00 00 02 00 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00 20 00 00 60 2E 69 64 61 74 61 00 00 00 00 00 00 00 20 00 00 00 02 00 00 00 04 00 00 00 00 00 00 00 00 00 00 00 00 00 00 40 00 00 C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 3C 20 00 00 00 00 00 00 00 00 00 00 24 20 00 00 34 20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 4B 45 52 4E 45 4C 33 32 2E 64 6C 6C 00 00 00 00 01 00 00 80 00 00 00 00 01 00 00 80 00 00 00 00

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  • Sorting and Re-arranging List of HashMaps

    - by HonorGod
    I have a List which is straight forward representation of a database table. I am trying to sort and apply some magic after the data is loaded into List of HashMaps. In my case this is the only hard and fast way of doing it becoz I have a rules engine that actually updates the values in the HashMap after several computations. Here is a sample data representation of the HashMap (List of HashMap) - {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=21, toDate=Tue Mar 23 10:54:12 EDT 2010, actionId=1234} {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=11, toDate=Wed Mar 17 10:54:12 EDT 2010, actionId=456} {fromDate=Sat Mar 20 10:54:12 EDT 2010, eventId=20, toDate=Thu Apr 01 10:54:12 EDT 2010, actionId=1234} {fromDate=Wed Mar 24 10:54:12 EDT 2010, eventId=22, toDate=Sat Mar 27 10:54:12 EDT 2010, actionId=1234} {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=11, toDate=Fri Mar 26 10:54:12 EDT 2010, actionId=1234} {fromDate=Sat Mar 20 10:54:12 EDT 2010, eventId=11, toDate=Wed Mar 31 10:54:12 EDT 2010, actionId=1234} {fromDate=Mon Mar 15 10:54:12 EDT 2010, eventId=12, toDate=Wed Mar 17 10:54:12 EDT 2010, actionId=567} I am trying to achieve couple of things - 1) Sort the list by actionId and eventId after which the data would look like - {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=11, toDate=Wed Mar 17 10:54:12 EDT 2010, actionId=456} {fromDate=Mon Mar 15 10:54:12 EDT 2010, eventId=12, toDate=Wed Mar 17 10:54:12 EDT 2010, actionId=567} {fromDate=Wed Mar 24 10:54:12 EDT 2010, eventId=22, toDate=Sat Mar 27 10:54:12 EDT 2010, actionId=1234} {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=21, toDate=Tue Mar 23 10:54:12 EDT 2010, actionId=1234} {fromDate=Sat Mar 20 10:54:12 EDT 2010, eventId=20, toDate=Thu Apr 01 10:54:12 EDT 2010, actionId=1234} {fromDate=Wed Mar 17 10:54:12 EDT 2010, eventId=11, toDate=Fri Mar 26 10:54:12 EDT 2010, actionId=1234} {fromDate=Sat Mar 20 10:54:12 EDT 2010, eventId=11, toDate=Wed Mar 31 10:54:12 EDT 2010, actionId=1234} 2) If we group the above list by actionId they would be resolved into 3 groups - actionId=1234, actionId=567 and actionId=456. Now here is my question - For each group having the same eventId, I need to update the records so that they have wider fromDate to toDate. Meaning, if you consider the last two rows they have same actionId = 1234 and same eventId = 11. Now we can to pick the least fromDate from those 2 records which is Wed Mar 17 10:54:12 and farther toDate which is Wed Mar 31 10:54:12 and update those 2 record's fromDate and toDate to Wed Mar 17 10:54:12 and Wed Mar 31 10:54:12 respectively. Any ideas? PS: I already have some pseudo code to start with. import java.util.ArrayList; import java.util.Calendar; import java.util.Collections; import java.util.Comparator; import java.util.Date; import java.util.HashMap; import java.util.List; import org.apache.commons.lang.builder.CompareToBuilder; public class Tester { boolean ascending = true ; boolean sortInstrumentIdAsc = true ; boolean sortEventTypeIdAsc = true ; public static void main(String args[]) { Tester tester = new Tester() ; tester.printValues() ; } public void printValues () { List<HashMap<String,Object>> list = new ArrayList<HashMap<String,Object>>() ; HashMap<String,Object> map = new HashMap<String,Object>(); map.put("actionId", new Integer(1234)) ; map.put("eventId", new Integer(21)) ; map.put("fromDate", getDate(1) ) ; map.put("toDate", getDate(7) ) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(456)) ; map.put("eventId", new Integer(11)) ; map.put("fromDate", getDate(1)) ; map.put("toDate", getDate(1) ) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(1234)) ; map.put("eventId", new Integer(20)) ; map.put("fromDate", getDate(4) ) ; map.put("toDate", getDate(16) ) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(1234)) ; map.put("eventId", new Integer(22)) ; map.put("fromDate",getDate(8) ) ; map.put("toDate", getDate(11)) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(1234)) ; map.put("eventId", new Integer(11)) ; map.put("fromDate",getDate(1) ) ; map.put("toDate", getDate(10) ) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(1234)) ; map.put("eventId", new Integer(11)) ; map.put("fromDate",getDate(4) ) ; map.put("toDate", getDate(15) ) ; list.add(map); map = new HashMap<String,Object>(); map.put("actionId", new Integer(567)) ; map.put("eventId", new Integer(12)) ; map.put("fromDate", getDate(-1) ) ; map.put("toDate",getDate(1)) ; list.add(map); System.out.println("\n Before Sorting \n "); for(int j = 0 ; j < list.size() ; j ++ ) System.out.println(list.get(j)); Collections.sort ( list , new HashMapComparator2 () ) ; System.out.println("\n After Sorting \n "); for(int j = 0 ; j < list.size() ; j ++ ) System.out.println(list.get(j)); } public static Date getDate(int days) { Calendar cal = Calendar.getInstance(); cal.setTime(new Date()); cal.add(Calendar.DATE, days); return cal.getTime() ; } public class HashMapComparator2 implements Comparator { public int compare ( Object object1 , Object object2 ) { if ( ascending == true ) { return new CompareToBuilder() .append(( ( HashMap ) object1 ).get ( "actionId" ), ( ( HashMap ) object2 ).get ( "actionId" )) .append(( ( HashMap ) object2 ).get ( "eventId" ), ( ( HashMap ) object1 ).get ( "eventId" )) .toComparison(); } else { return new CompareToBuilder() .append(( ( HashMap ) object2 ).get ( "actionId" ), ( ( HashMap ) object1 ).get ( "actionId" )) .append(( ( HashMap ) object2 ).get ( "eventId" ), ( ( HashMap ) object1 ).get ( "eventId" )) .toComparison(); } } } }

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  • change password code error

    - by ejah85
    I've created a code to change a password. Now it seem contain an error. When I fill in the form to change password, and click save the error message: Warning: mysql_real_escape_string() expects parameter 2 to be resource, null given in C:\Program Files\xampp\htdocs\e-Complaint(FYP)\userChangePass.php on line 103 Warning: mysql_real_escape_string() expects parameter 2 to be resource, null given in C:\Program Files\xampp\htdocs\e-Complaint(FYP)\userChangePass.php on line 103 I really don’t know what the error message means. Please guys. Help me fix it. Here's is the code: <?php session_start(); ?> <?php # change password.php //set the page title and include the html header. $page_title = 'Change Your Password'; //include('templates/header.inc'); if(isset($_POST['submit'])){//handle the form require_once('connectioncomplaint.php');//connect to the db. //include "connectioncomplaint.php"; //create a function for escaping the data. function escape_data($data){ global $dbc;//need the connection. if(ini_get('magic_quotes_gpc')){ $data=stripslashes($data); } return mysql_real_escape_string($data, $dbc); }//end function $message=NULL;//create the empty new variable. //check for a username if(empty($_POST['userid'])){ $u=FALSE; $message .='<p> You forgot enter your userid!</p>'; }else{ $u=escape_data($_POST['userid']); } //check for existing password if(empty($_POST['password'])){ $p=FALSE; $message .='<p>You forgot to enter your existing password!</p>'; }else{ $p=escape_data($_POST['password']); } //check for a password and match againts the comfirmed password. if(empty($_POST['password1'])) { $np=FALSE; $message .='<p> you forgot to enter your new password!</p>'; }else{ if($_POST['password1'] == $_POST['password2']){ $np=escape_data($_POST['password1']); }else{ $np=FALSE; $message .='<p> your new password did not match the confirmed new password!</p>'; } } if($u && $p && $np){//if everything's ok. $query="SELECT userid FROM access WHERE (userid='$u' AND password=PASSWORD('$p'))"; $result=@mysql_query($query); $num=mysql_num_rows($result); if($num == 1){ $row=mysql_fetch_array($result, MYSQL_NUM); //make the query $query="UPDATE access SET password=PASSWORD('$np') WHERE userid=$row[0]"; $result=@mysql_query($query);//run the query. if(mysql_affected_rows() == 1) {//if it run ok. //send an email,if desired. echo '<p><b>your password has been changed.</b></p>'; include('templates/footer.inc');//include the HTML footer. exit();//quit the script. }else{//if it did not run OK. $message= '<p>Your password could not be change due to a system error.We apolpgize for any inconvenience.</p><p>' .mysql_error() .'</p>'; } }else{ $message= '<p> Your username and password do not match our records.</p>'; } mysql_close();//close the database connection. }else{ $message .='<p>Please try again.</p>'; } }//end oh=f the submit conditional. //print the error message if there is one. if(isset($message)){ echo'<font color="red">' , $message, '</font>'; } ?> <form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post"> <body> <script language="JavaScript1.2">mmLoadMenus();</script> <table width="604" height="599" border="0" align="center" cellpadding="0" cellspacing="0"> <tr> <td height="130" colspan="7"><img src="images/banner(E-Complaint)-.jpg" width="759" height="130" /></td> </tr> <tr> <td width="100" height="30" bgcolor="#ABD519"></td> <td width="100" bgcolor="#ABD519"></td> <td width="100" bgcolor="#ABD519"></td> <td width="100" bgcolor="#ABD519"></td> <td width="100" bgcolor="#ABD519"></td> <td width="160" bgcolor="#ABD519"> <?php include "header.php"; ?>&nbsp;</td> </tr> <tr> <td colspan="7" bgcolor="#FFFFFF"> <fieldset><legend> Enter your information in the form below:</legend> <p><b>User ID:</b> <input type="text" name="username" size="10" maxlength="20" value="<?php if(isset($_POST['userid'])) echo $_POST['userid']; ?>" /></p> <p><b>Current Password:</b> <input type="password" name="password" size="20" maxlength="20" /></p> <p><b>New Password:</b> <input type="password" name="password1" size="20" maxlength="20" /></p> <p><b>Confirm New Password:</b> <input type="password" name="password2" size="20" maxlength="20" /></p> </fieldset> <div align="center"> <input type="submit" name="submit" value="Change My Password" /></div> </form><!--End Form--> </td> </tr> </table> </body> </html>

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  • Loosely coupled .NET Cache Provider using Dependency Injection

    - by Rhames
    I have recently been reading the excellent book “Dependency Injection in .NET”, written by Mark Seemann. I do not generally buy software development related books, as I never seem to have the time to read them, but I have found the time to read Mark’s book, and it was time well spent I think. Reading the ideas around Dependency Injection made me realise that the Cache Provider code I wrote about earlier (see http://geekswithblogs.net/Rhames/archive/2011/01/10/using-the-asp.net-cache-to-cache-data-in-a-model.aspx) could be refactored to use Dependency Injection, which should produce cleaner code. The goals are to: Separate the cache provider implementation (using the ASP.NET data cache) from the consumers (loose coupling). This will also mean that the dependency on System.Web for the cache provider does not ripple down into the layers where it is being consumed (such as the domain layer). Provide a decorator pattern to allow a consumer of the cache provider to be implemented separately from the base consumer (i.e. if we have a base repository, we can decorate this with a caching version). Although I used the term repository, in reality the cache consumer could be just about anything. Use constructor injection to provide the Dependency Injection, with a suitable DI container (I use Castle Windsor). The sample code for this post is available on github, https://github.com/RobinHames/CacheProvider.git ICacheProvider In the sample code, the key interface is ICacheProvider, which is in the domain layer. 1: using System; 2: using System.Collections.Generic; 3:   4: namespace CacheDiSample.Domain 5: { 6: public interface ICacheProvider<T> 7: { 8: T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry); 9: IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry); 10: } 11: }   This interface contains two methods to retrieve data from the cache, either as a single instance or as an IEnumerable. the second paramerter is of type Func<T>. This is the method used to retrieve data if nothing is found in the cache. The ASP.NET implementation of the ICacheProvider interface needs to live in a project that has a reference to system.web, typically this will be the root UI project, or it could be a separate project. The key thing is that the domain or data access layers do not need system.web references adding to them. In my sample MVC application, the CacheProvider is implemented in the UI project, in a folder called “CacheProviders”: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Web; 5: using System.Web.Caching; 6: using CacheDiSample.Domain; 7:   8: namespace CacheDiSample.CacheProvider 9: { 10: public class CacheProvider<T> : ICacheProvider<T> 11: { 12: public T Fetch(string key, Func<T> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry) 13: { 14: return FetchAndCache<T>(key, retrieveData, absoluteExpiry, relativeExpiry); 15: } 16:   17: public IEnumerable<T> Fetch(string key, Func<IEnumerable<T>> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry) 18: { 19: return FetchAndCache<IEnumerable<T>>(key, retrieveData, absoluteExpiry, relativeExpiry); 20: } 21:   22: #region Helper Methods 23:   24: private U FetchAndCache<U>(string key, Func<U> retrieveData, DateTime? absoluteExpiry, TimeSpan? relativeExpiry) 25: { 26: U value; 27: if (!TryGetValue<U>(key, out value)) 28: { 29: value = retrieveData(); 30: if (!absoluteExpiry.HasValue) 31: absoluteExpiry = Cache.NoAbsoluteExpiration; 32:   33: if (!relativeExpiry.HasValue) 34: relativeExpiry = Cache.NoSlidingExpiration; 35:   36: HttpContext.Current.Cache.Insert(key, value, null, absoluteExpiry.Value, relativeExpiry.Value); 37: } 38: return value; 39: } 40:   41: private bool TryGetValue<U>(string key, out U value) 42: { 43: object cachedValue = HttpContext.Current.Cache.Get(key); 44: if (cachedValue == null) 45: { 46: value = default(U); 47: return false; 48: } 49: else 50: { 51: try 52: { 53: value = (U)cachedValue; 54: return true; 55: } 56: catch 57: { 58: value = default(U); 59: return false; 60: } 61: } 62: } 63:   64: #endregion 65:   66: } 67: }   The FetchAndCache helper method checks if the specified cache key exists, if it does not, the Func<U> retrieveData method is called, and the results are added to the cache. Using Castle Windsor to register the cache provider In the MVC UI project (my application root), Castle Windsor is used to register the CacheProvider implementation, using a Windsor Installer: 1: using Castle.MicroKernel.Registration; 2: using Castle.MicroKernel.SubSystems.Configuration; 3: using Castle.Windsor; 4:   5: using CacheDiSample.Domain; 6: using CacheDiSample.CacheProvider; 7:   8: namespace CacheDiSample.WindsorInstallers 9: { 10: public class CacheInstaller : IWindsorInstaller 11: { 12: public void Install(IWindsorContainer container, IConfigurationStore store) 13: { 14: container.Register( 15: Component.For(typeof(ICacheProvider<>)) 16: .ImplementedBy(typeof(CacheProvider<>)) 17: .LifestyleTransient()); 18: } 19: } 20: }   Note that the cache provider is registered as a open generic type. Consuming a Repository I have an existing couple of repository interfaces defined in my domain layer: IRepository.cs 1: using System; 2: using System.Collections.Generic; 3:   4: using CacheDiSample.Domain.Model; 5:   6: namespace CacheDiSample.Domain.Repositories 7: { 8: public interface IRepository<T> 9: where T : EntityBase 10: { 11: T GetById(int id); 12: IList<T> GetAll(); 13: } 14: }   IBlogRepository.cs 1: using System; 2: using CacheDiSample.Domain.Model; 3:   4: namespace CacheDiSample.Domain.Repositories 5: { 6: public interface IBlogRepository : IRepository<Blog> 7: { 8: Blog GetByName(string name); 9: } 10: }   These two repositories are implemented in the DataAccess layer, using Entity Framework to retrieve data (this is not important though). One important point is that in the BaseRepository implementation of IRepository, the methods are virtual. This will allow the decorator to override them. The BlogRepository is registered in a RepositoriesInstaller, again in the MVC UI project. 1: using Castle.MicroKernel.Registration; 2: using Castle.MicroKernel.SubSystems.Configuration; 3: using Castle.Windsor; 4:   5: using CacheDiSample.Domain.CacheDecorators; 6: using CacheDiSample.Domain.Repositories; 7: using CacheDiSample.DataAccess; 8:   9: namespace CacheDiSample.WindsorInstallers 10: { 11: public class RepositoriesInstaller : IWindsorInstaller 12: { 13: public void Install(IWindsorContainer container, IConfigurationStore store) 14: { 15: container.Register(Component.For<IBlogRepository>() 16: .ImplementedBy<BlogRepository>() 17: .LifestyleTransient() 18: .DependsOn(new 19: { 20: nameOrConnectionString = "BloggingContext" 21: })); 22: } 23: } 24: }   Now I can inject a dependency on the IBlogRepository into a consumer, such as a controller in my sample code: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Web; 5: using System.Web.Mvc; 6:   7: using CacheDiSample.Domain.Repositories; 8: using CacheDiSample.Domain.Model; 9:   10: namespace CacheDiSample.Controllers 11: { 12: public class HomeController : Controller 13: { 14: private readonly IBlogRepository blogRepository; 15:   16: public HomeController(IBlogRepository blogRepository) 17: { 18: if (blogRepository == null) 19: throw new ArgumentNullException("blogRepository"); 20:   21: this.blogRepository = blogRepository; 22: } 23:   24: public ActionResult Index() 25: { 26: ViewBag.Message = "Welcome to ASP.NET MVC!"; 27:   28: var blogs = blogRepository.GetAll(); 29:   30: return View(new Models.HomeModel { Blogs = blogs }); 31: } 32:   33: public ActionResult About() 34: { 35: return View(); 36: } 37: } 38: }   Consuming the Cache Provider via a Decorator I used a Decorator pattern to consume the cache provider, this means my repositories follow the open/closed principle, as they do not require any modifications to implement the caching. It also means that my controllers do not have any knowledge of the caching taking place, as the DI container will simply inject the decorator instead of the root implementation of the repository. The first step is to implement a BlogRepository decorator, with the caching logic in it. Note that this can reside in the domain layer, as it does not require any knowledge of the data access methods. BlogRepositoryWithCaching.cs 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Text; 5:   6: using CacheDiSample.Domain.Model; 7: using CacheDiSample.Domain; 8: using CacheDiSample.Domain.Repositories; 9:   10: namespace CacheDiSample.Domain.CacheDecorators 11: { 12: public class BlogRepositoryWithCaching : IBlogRepository 13: { 14: // The generic cache provider, injected by DI 15: private ICacheProvider<Blog> cacheProvider; 16: // The decorated blog repository, injected by DI 17: private IBlogRepository parentBlogRepository; 18:   19: public BlogRepositoryWithCaching(IBlogRepository parentBlogRepository, ICacheProvider<Blog> cacheProvider) 20: { 21: if (parentBlogRepository == null) 22: throw new ArgumentNullException("parentBlogRepository"); 23:   24: this.parentBlogRepository = parentBlogRepository; 25:   26: if (cacheProvider == null) 27: throw new ArgumentNullException("cacheProvider"); 28:   29: this.cacheProvider = cacheProvider; 30: } 31:   32: public Blog GetByName(string name) 33: { 34: string key = string.Format("CacheDiSample.DataAccess.GetByName.{0}", name); 35: // hard code 5 minute expiry! 36: TimeSpan relativeCacheExpiry = new TimeSpan(0, 5, 0); 37: return cacheProvider.Fetch(key, () => 38: { 39: return parentBlogRepository.GetByName(name); 40: }, 41: null, relativeCacheExpiry); 42: } 43:   44: public Blog GetById(int id) 45: { 46: string key = string.Format("CacheDiSample.DataAccess.GetById.{0}", id); 47:   48: // hard code 5 minute expiry! 49: TimeSpan relativeCacheExpiry = new TimeSpan(0, 5, 0); 50: return cacheProvider.Fetch(key, () => 51: { 52: return parentBlogRepository.GetById(id); 53: }, 54: null, relativeCacheExpiry); 55: } 56:   57: public IList<Blog> GetAll() 58: { 59: string key = string.Format("CacheDiSample.DataAccess.GetAll"); 60:   61: // hard code 5 minute expiry! 62: TimeSpan relativeCacheExpiry = new TimeSpan(0, 5, 0); 63: return cacheProvider.Fetch(key, () => 64: { 65: return parentBlogRepository.GetAll(); 66: }, 67: null, relativeCacheExpiry) 68: .ToList(); 69: } 70: } 71: }   The key things in this caching repository are: I inject into the repository the ICacheProvider<Blog> implementation, via the constructor. This will make the cache provider functionality available to the repository. I inject the parent IBlogRepository implementation (which has the actual data access code), via the constructor. This will allow the methods implemented in the parent to be called if nothing is found in the cache. I override each of the methods implemented in the repository, including those implemented in the generic BaseRepository. Each override of these methods follows the same pattern. It makes a call to the CacheProvider.Fetch method, and passes in the parentBlogRepository implementation of the method as the retrieval method, to be used if nothing is present in the cache. Configuring the Caching Repository in the DI Container The final piece of the jigsaw is to tell Castle Windsor to use the BlogRepositoryWithCaching implementation of IBlogRepository, but to inject the actual Data Access implementation into this decorator. This is easily achieved by modifying the RepositoriesInstaller to use Windsor’s implicit decorator wiring: 1: using Castle.MicroKernel.Registration; 2: using Castle.MicroKernel.SubSystems.Configuration; 3: using Castle.Windsor; 4:   5: using CacheDiSample.Domain.CacheDecorators; 6: using CacheDiSample.Domain.Repositories; 7: using CacheDiSample.DataAccess; 8:   9: namespace CacheDiSample.WindsorInstallers 10: { 11: public class RepositoriesInstaller : IWindsorInstaller 12: { 13: public void Install(IWindsorContainer container, IConfigurationStore store) 14: { 15:   16: // Use Castle Windsor implicit wiring for the block repository decorator 17: // Register the outermost decorator first 18: container.Register(Component.For<IBlogRepository>() 19: .ImplementedBy<BlogRepositoryWithCaching>() 20: .LifestyleTransient()); 21: // Next register the IBlogRepository inmplementation to inject into the outer decorator 22: container.Register(Component.For<IBlogRepository>() 23: .ImplementedBy<BlogRepository>() 24: .LifestyleTransient() 25: .DependsOn(new 26: { 27: nameOrConnectionString = "BloggingContext" 28: })); 29: } 30: } 31: }   This is all that is needed. Now if the consumer of the repository makes a call to the repositories method, it will be routed via the caching mechanism. You can test this by stepping through the code, and seeing that the DataAccess.BlogRepository code is only called if there is no data in the cache, or this has expired. The next step is to add the SQL Cache Dependency support into this pattern, this will be a future post.

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