Search Results

Search found 20786 results on 832 pages for 'static variables'.

Page 234/832 | < Previous Page | 230 231 232 233 234 235 236 237 238 239 240 241  | Next Page >

  • Extending Enums, Overkill?

    - by CkH
    I have an object that needs to be serialized to an EDI format. For this example we'll say it's a car. A car might not be the best example b/c options change over time, but for the real object the Enums will never change. I have many Enums like the following with custom attributes applied. public enum RoofStyle { [DisplayText("Glass Top")] [StringValue("GTR")] Glass, [DisplayText("Convertible Soft Top")] [StringValue("CST")] ConvertibleSoft, [DisplayText("Hard Top")] [StringValue("HT ")] HardTop, [DisplayText("Targa Top")] [StringValue("TT ")] Targa, } The Attributes are accessed via Extension methods: public static string GetStringValue(this Enum value) { // Get the type Type type = value.GetType(); // Get fieldinfo for this type FieldInfo fieldInfo = type.GetField(value.ToString()); // Get the stringvalue attributes StringValueAttribute[] attribs = fieldInfo.GetCustomAttributes( typeof(StringValueAttribute), false) as StringValueAttribute[]; // Return the first if there was a match. return attribs.Length > 0 ? attribs[0].StringValue : null; } public static string GetDisplayText(this Enum value) { // Get the type Type type = value.GetType(); // Get fieldinfo for this type FieldInfo fieldInfo = type.GetField(value.ToString()); // Get the DisplayText attributes DisplayTextAttribute[] attribs = fieldInfo.GetCustomAttributes( typeof(DisplayTextAttribute), false) as DisplayTextAttribute[]; // Return the first if there was a match. return attribs.Length > 0 ? attribs[0].DisplayText : value.ToString(); } There is a custom EDI serializer that serializes based on the StringValue attributes like so: StringBuilder sb = new StringBuilder(); sb.Append(car.RoofStyle.GetStringValue()); sb.Append(car.TireSize.GetStringValue()); sb.Append(car.Model.GetStringValue()); ... There is another method that can get Enum Value from StringValue for Deserialization: car.RoofStyle = Enums.GetCode<RoofStyle>(EDIString.Substring(4, 3)) Defined as: public static class Enums { public static T GetCode<T>(string value) { foreach (object o in System.Enum.GetValues(typeof(T))) { if (((Enum)o).GetStringValue() == value.ToUpper()) return (T)o; } throw new ArgumentException("No code exists for type " + typeof(T).ToString() + " corresponding to value of " + value); } } And Finally, for the UI, the GetDisplayText() is used to show the user friendly text. What do you think? Overkill? Is there a better way? or Goldie Locks (just right)? Just want to get feedback before I intergrate it into my personal framework permanently. Thanks.

    Read the article

  • What's a clean way to break up a DataTable into chunks of a fixed size with Linq?

    - by Michael Haren
    Update: Here's a similar question Suppose I have a DataTable with a few thousand DataRows in it. I'd like to break up the table into chunks of smaller rows for processing. I thought C#3's improved ability to work with data might help. This is the skeleton I have so far: DataTable Table = GetTonsOfData(); // Chunks should be any IEnumerable<Chunk> type var Chunks = ChunkifyTableIntoSmallerChunksSomehow; // ** help here! ** foreach(var Chunk in Chunks) { // Chunk should be any IEnumerable<DataRow> type ProcessChunk(Chunk); } Any suggestions on what should replace ChunkifyTableIntoSmallerChunksSomehow? I'm really interested in how someone would do this with access C#3 tools. If attempting to apply these tools is inappropriate, please explain! Update 3 (revised chunking as I really want tables, not ienumerables; going with an extension method--thanks Jacob): Final implementation: Extension method to handle the chunking: public static class HarenExtensions { public static IEnumerable<DataTable> Chunkify(this DataTable table, int chunkSize) { for (int i = 0; i < table.Rows.Count; i += chunkSize) { DataTable Chunk = table.Clone(); foreach (DataRow Row in table.Select().Skip(i).Take(chunkSize)) { Chunk.ImportRow(Row); } yield return Chunk; } } } Example consumer of that extension method, with sample output from an ad hoc test: class Program { static void Main(string[] args) { DataTable Table = GetTonsOfData(); foreach (DataTable Chunk in Table.Chunkify(100)) { Console.WriteLine("{0} - {1}", Chunk.Rows[0][0], Chunk.Rows[Chunk.Rows.Count - 1][0]); } Console.ReadLine(); } static DataTable GetTonsOfData() { DataTable Table = new DataTable(); Table.Columns.Add(new DataColumn()); for (int i = 0; i < 1000; i++) { DataRow Row = Table.NewRow(); Row[0] = i; Table.Rows.Add(Row); } return Table; } }

    Read the article

  • log4j performance

    - by Bob
    Hi, I'm developing a web app, and I'd like to log some information to help me improve and observe the app. (I'm using Tomcat6) First I thought I would use StringBuilders, append the logs to them and a task would persist them into the database like every 2 minutes. Because I was worried about the out-of-the-box logging system's performance. Then I made some test. Especially with log4j. Here is my code: Main.java public static void main(String[] args) { Thread[] threads = new Thread[LoggerThread.threadsNumber]; for(int i = 0; i < LoggerThread.threadsNumber; ++i){ threads[i] = new Thread(new LoggerThread("name - " + i)); } LoggerThread.startTimestamp = System.currentTimeMillis(); for(int i = 0; i < LoggerThread.threadsNumber; ++i){ threads[i].start(); } LoggerThread.java public class LoggerThread implements Runnable{ public static int threadsNumber = 10; public static long startTimestamp; private static int counter = 0; private String name; public LoggerThread(String name) { this.name = name; } private Logger log = Logger.getLogger(this.getClass()); @Override public void run() { for(int i=0; i<10000; ++i){ log.info(name + ": " + i); if(i == 9999){ int c = increaseCounter(); if(c == threadsNumber){ System.out.println("Elapsed time: " + (System.currentTimeMillis() - startTimestamp)); } } } } private synchronized int increaseCounter(){ return ++counter; } } } log4j.properties log4j.logger.main.LoggerThread=debug, f log4j.appender.f=org.apache.log4j.RollingFileAppender log4j.appender.f.layout=org.apache.log4j.PatternLayout log4j.appender.f.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n log4j.appender.f.File=c:/logs/logging.log log4j.appender.f.MaxFileSize=15000KB log4j.appender.f.MaxBackupIndex=50 I think this is a very common configuration for log4j. First I used log4j 1.2.14 then I realized there was a newer version, so I switched to 1.2.16 Here are the figures (all in millisec) LoggerThread.threadsNumber = 10 1.2.14: 4235, 4267, 4328, 4282 1.2.16: 2780, 2781, 2797, 2781 LoggerThread.threadsNumber = 100 1.2.14: 41312, 41014, 42251 1.2.16: 25606, 25729, 25922 I think this is very fast. Don't forget that: in every cycle the run method not just log into the file, it has to concatenate strings (name + ": " + i), and check an if test (i == 9999). When threadsNumber is 10, there are 100.000 loggings and if tests and concatenations. When it is 100, there are 1.000.000 loggings and if tests and concatenations. (I've read somewhere JVM uses StringBuilder's append for concatenation, not simple concatenation). Did I missed something? Am I doing something wrong? Did I forget any factor that could decrease the performance? If these figures are correct I think, I don't have to worry about log4j's performance even if I heavily log, do I?

    Read the article

  • C# Simple Event Handler for Setting Alarm

    - by yeeen
    Why does the following line "alarm.AlarmEvent += new AlarmEventHandler(alarm_Sound);" gives me "An object reference is required for the non-static field, method, or property 'AlarmClock.Alarm.alarm_Sound(object, System.EventArgs)'" public static void Main(string[] args) { Alarm alarm = new Alarm(new DateTime(2010, 4, 7, 23, 2, 0)); alarm.Set(); alarm.AlarmEvent += new AlarmEventHandler(alarm_Sound); } Full source code here: Program.cs AlarmEventArgs

    Read the article

  • What am I missing in this ASP.NET XSS Security Helper class?

    - by smartcaveman
    I need a generic method for preventing XSS attacks in ASP.NET. The approach I came up with is a ValidateRequest method that evaluates the HttpRequest for any potential issues, and if issues are found, redirect the user to the same page, but in a away that is not threatening to the application. (Source code below) While I know this method will prevent most XSS attacks, I am not certain that I am adequately preventing all possible attacks while also minimizing false positives. So, what is the most effective way to adequately prevent all possible attacks, while minimizing false positives? Are there changes I should make to the helper class below, or is there an alternative approach or third party library that offers something more convincing? public static class XssSecurity { public const string PotentialXssAttackExpression = "(http(s)*(%3a|:))|(ftp(s)*(%3a|:))|(javascript)|(alert)|(((\\%3C) <)[^\n]+((\\%3E) >))"; private static readonly Regex PotentialXssAttackRegex = new Regex(PotentialXssAttackExpression, RegexOptions.IgnoreCase); public static bool IsPotentialXssAttack(this HttpRequest request) { if(request != null) { string query = request.QueryString.ToString(); if(!string.IsNullOrEmpty(query) && PotentialXssAttackRegex.IsMatch(query)) return true; if(request.HttpMethod.Equals("post", StringComparison.InvariantCultureIgnoreCase)) { string form = request.Form.ToString(); if (!string.IsNullOrEmpty(form) && PotentialXssAttackRegex.IsMatch(form)) return true; } if(request.Cookies.Count > 0) { foreach(HttpCookie cookie in request.Cookies) { if(PotentialXssAttackRegex.IsMatch(cookie.Value)) { return true; } } } } return false; } public static void ValidateRequest(this HttpContext context, string redirectToPath = null) { if(context == null || !context.Request.IsPotentialXssAttack()) return; // expire all cookies foreach(HttpCookie cookie in context.Request.Cookies) { cookie.Expires = DateTime.Now.Subtract(TimeSpan.FromDays(1)); context.Response.Cookies.Set(cookie); } // redirect to safe path bool redirected = false; if(redirectToPath != null) { try { context.Response.Redirect(redirectToPath,true); redirected = true; } catch { redirected = false; } } if (redirected) return; string safeUrl = context.Request.Url.AbsolutePath.Replace(context.Request.Url.Query, string.Empty); context.Response.Redirect(safeUrl,true); } }

    Read the article

  • Built in Analyzer in Xcode 3.1.4

    - by Mustafa
    Hi all, I wonder if the built in Analyzer in Xcode 3.1.4 makes it redundant to use LLVM/Clang Static Analyzer separately? Please refer to the original article here: Finding memory leaks with the LLVM/Clang Static Analyzer Thanks.

    Read the article

  • How to load a springframework ApplicationContext from Jython

    - by staticman
    I have a class that loads a springframework application context like so: package com.offlinesupport; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class OfflineScriptSupport { private static ApplicationContext appCtx; public static final void initialize() { appCtx = new ClassPathXmlApplicationContext( new String[] { "mycontext.spring.xml" } ); } public static final ApplicationContext getApplicationContext() { return appCtx; } public static final void main( String[] args ) { System.out.println( "Starting..." ); initialize(); System.out.println( "loaded" ); } } The class OfflineScriptSupport, and the file mycontext.spring.xml are each deployed into separate jars (along with other classes and resources in their respective modules). Lets say the jar files are OfflineScriptSupport.jar and *MyContext.jar". mycontext.spring.xml is put at the root of the jar. In a Jython script (*myscript.jy"), I try to call the initialize method to create the application context: from com.offlinesupport import OfflineScriptSupport OfflineScriptSupport.initialize(); I execute the Jython script with the following command (from Linux): jython -Dpython.path=spring.jar:OfflineScriptSupport.jar:MyContext.jar myscript.jy The Springframework application context cannot find the mycontext.spring.xml file. It displays the following error: java.io.FileNotFoundException: class path resource [mycontext.spring.xml] cannot be opened because it does not exist at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:137) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:167) at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:148) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:126) at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:142) at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:113) at org.springframework.context.support.AbstractXmlApplicationContext.loadBeanDefinitions(AbstractXmlApplicationContext.java:81) at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:89) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:269) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:87) at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:72) at com.offlinesupport.OfflineScriptSupport.initialize(OfflineScriptSupport.java:27) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) If I run the jar directly from Java (using the main entry point in OfflineScriptSupport) it works and there is no error thrown. Is there something special about the way Jython handles classpaths making the Springframework's ClassPathXmlApplicationContext not work (i.e. not be able to find resource files in the classpath)?

    Read the article

  • How would I set up this enum to return the image I want?

    - by Justen
    I'm trying to set up this enum so that it has the ability to return the correct image, though I'm struggling with a way to incorporate the context since it is in a separate class. public enum CubeType { GREEN { public Drawable getImage() { return Context.getResources().getDrawable( R.drawable.cube_green ); } }; abstract public Drawable getImage(); } The error I'm getting is: Cannot make a static reference to the non-static method getResources() from the type Context

    Read the article

  • trace this java method

    - by Bader
    public static int ABC(int x, int y) { if(y==0) return(0); else return(x + ABC(x,y-1)); } /** * @param args */ public static void main(String[] args) { // TODO Auto-generated method stub System.out.println(ABC(5,3)); }

    Read the article

  • Call a c# method from Javascript

    - by Luis
    Hi i want to call a C# method.. I already tryed with webmethod, but in the c# method i will not have acces to textbox or others controls. this is how i done without success.. http://www.singingeels.com/Articles/Using_Page_Methods_in_ASPNET_AJAX.aspx With static works, but i want without static, so i can access to the controls in the aspx and validate the page. how can i do it?

    Read the article

  • Response is not available in this context when creation cookie's

    - by Sadegh
    hi i defined one class to create cookie by received parameter's from user. when i want to add cookie to context i receive an exception. My Class public static class ManageCookies { public static void Create(string name, string value) { HttpCookie cookie = new HttpCookie(name); cookie.Value = value; cookie.Expires = DateTime.Now.AddYears(1); HttpContext.Current.Response.Cookies.Add(cookie); } } Occured Exception: Response is not available in this context.

    Read the article

  • How to create constant NSString by concatenating strings in Obj-C ?

    - by eric-morand
    Hi guys, I'm trying to instanciate a constant NSString by concatanating other NSString instances. Here is what I'm doing in my implementation file : static NSString *const MY_CONST = @"TEST"; static NSString *const MY_CONCATENATE_CONST = [NSString stringWithFormat:@"STRING %@", MY_CONST]; It leads to the following compilation error : Initializer element is not constant I suppose this is because stringWithFormat doesn't return a constant NSString, but since there is no other way to concatenate strings in Obj-C, what am I supposed to do ? Thanks for your help, Eric.

    Read the article

  • Problem running code with JML2 in Eclipse

    - by devoured elysium
    I'm having trouble running JML2 in Eclipse. I have the foolowing code: public class MainClass { public static void main(String[] args) { System.out.println(-9.0); } //@requires x >= 7.0 public static double getSquare(double x) { return Math.sqrt(x); } } The error I'm getting is: Is there anything wrong with the syntax I've used? Thanks

    Read the article

  • Library is missing

    - by andrejs-igumenovs
    Corresponding to Wiki (http://code.google.com/p/core-plot/wiki/UsingCorePlotInApplications): "Core Plot is built as a static library for iPhone, so you'll need to drag the libCorePlot-CocoaTouch.a static library from under the CorePlot-CocoaTouch.xcodeproj group to your target's Link Binary With Libraries folder." I do not see mentioned library there..

    Read the article

  • Why the output is not same ??

    - by javatechi
    public class swapex{ public static int var1, var2; public void badSwap(int var1, int var2){ int temp = var1; this.var1 = var2; this.var2 = temp; System.out.println("var1 " + var1 + " var2 "+ var2); } public static void main(String args[]) { swapex sw= new swapex(); sw.badSwap(10,20); System.out.println("var1 " + var1 + " var2 "+ var2); } }

    Read the article

  • twitter4j code doent work on ICS and JellyBean help me

    - by swapnil adsure
    Hey guys i am using twitter4J to post tweet on twitter Here i Change the Code according to your suggestion . i do some google search. The problem is When i try to shift from main activity to twitter activity it show force close. Main activity is = "MainActivity" twitter activity is = "twiti_backup" I think there is problem in Manifestfile but i dont know what was it. public class twiti_backup extends Activity { private static final String TAG = "Blundell.TweetToTwitterActivity"; private static final String PREF_ACCESS_TOKEN = ""; private static final String PREF_ACCESS_TOKEN_SECRET = ""; private static final String CONSUMER_KEY = ""; private static final String CONSUMER_SECRET = ""; private static final String CALLBACK_URL = "android:///"; private SharedPreferences mPrefs; private Twitter mTwitter; private RequestToken mReqToken; private Button mLoginButton; private Button mTweetButton; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); Log.i(TAG, "Loading TweetToTwitterActivity"); setContentView(R.layout.twite); mPrefs = getSharedPreferences("twitterPrefs", MODE_PRIVATE); mTwitter = new TwitterFactory().getInstance(); mTwitter.setOAuthConsumer(CONSUMER_KEY, CONSUMER_SECRET); mLoginButton = (Button) findViewById(R.id.login_button); mTweetButton = (Button) findViewById(R.id.tweet_button); } public void buttonLogin(View v) { Log.i(TAG, "Login Pressed"); if (mPrefs.contains(PREF_ACCESS_TOKEN)) { Log.i(TAG, "Repeat User"); loginAuthorisedUser(); } else { Log.i(TAG, "New User"); loginNewUser(); } } public void buttonTweet(View v) { Log.i(TAG, "Tweet Pressed"); tweetMessage(); } private void loginNewUser() { try { Log.i(TAG, "Request App Authentication"); mReqToken = mTwitter.getOAuthRequestToken(CALLBACK_URL); Log.i(TAG, "Starting Webview to login to twitter"); WebView twitterSite = new WebView(this); twitterSite.loadUrl(mReqToken.getAuthenticationURL()); setContentView(twitterSite); } catch (TwitterException e) { Toast.makeText(this, "Twitter Login error, try again later", Toast.LENGTH_SHORT).show(); } } private void loginAuthorisedUser() { String token = mPrefs.getString(PREF_ACCESS_TOKEN, null); String secret = mPrefs.getString(PREF_ACCESS_TOKEN_SECRET, null); // Create the twitter access token from the credentials we got previously AccessToken at = new AccessToken(token, secret); mTwitter.setOAuthAccessToken(at); Toast.makeText(this, "Welcome back", Toast.LENGTH_SHORT).show(); enableTweetButton(); } @Override protected void onNewIntent(Intent intent) { super.onNewIntent(intent); Log.i(TAG, "New Intent Arrived"); dealWithTwitterResponse(intent); } @Override protected void onResume() { super.onResume(); Log.i(TAG, "Arrived at onResume"); } private void dealWithTwitterResponse(Intent intent) { Uri uri = intent.getData(); if (uri != null && uri.toString().startsWith(CALLBACK_URL)) { // If the user has just logged in String oauthVerifier = uri.getQueryParameter("oauth_verifier"); authoriseNewUser(oauthVerifier); } } private void authoriseNewUser(String oauthVerifier) { try { AccessToken at = mTwitter.getOAuthAccessToken(mReqToken, oauthVerifier); mTwitter.setOAuthAccessToken(at); saveAccessToken(at); // Set the content view back after we changed to a webview setContentView(R.layout.twite); enableTweetButton(); } catch (TwitterException e) { Toast.makeText(this, "Twitter auth error x01, try again later", Toast.LENGTH_SHORT).show(); } } private void enableTweetButton() { Log.i(TAG, "User logged in - allowing to tweet"); mLoginButton.setEnabled(false); mTweetButton.setEnabled(true); } private void tweetMessage() { try { mTwitter.updateStatus("Test - Tweeting with @Blundell_apps #AndroidDev Tutorial using #Twitter4j http://blog.blundell-apps.com/sending-a-tweet/"); Toast.makeText(this, "Tweet Successful!", Toast.LENGTH_SHORT).show(); } catch (TwitterException e) { Toast.makeText(this, "Tweet error, try again later", Toast.LENGTH_SHORT).show(); } } private void saveAccessToken(AccessToken at) { String token = at.getToken(); String secret = at.getTokenSecret(); Editor editor = mPrefs.edit(); editor.putString(PREF_ACCESS_TOKEN, token); editor.putString(PREF_ACCESS_TOKEN_SECRET, secret); editor.commit(); } } And here is Manifest <application android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name=".MainActivity" android:label="@string/title_activity_main" android:launchMode="singleInstance" android:configChanges="orientation|screenSize"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".twiti_backup" android:launchMode="singleInstance"> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="android.intent.category.BROWSABLE" /> <data android:scheme="android" android:host="callback_main" /> </activity> <activity android:name=".MyTwite"/> <activity android:name=".mp3" /> <activity android:name=".myfbapp" /> </application> Here is Log cat when i try to launch twiti_backup from main activity W/dalvikvm(16357): threadid=1: thread exiting with uncaught exception (group=0x4001d5a0) E/AndroidRuntime(16357): FATAL EXCEPTION: main E/AndroidRuntime(16357): java.lang.VerifyError: com.example.uitest.twiti_backup E/AndroidRuntime(16357): at java.lang.Class.newInstanceImpl(Native Method) E/AndroidRuntime(16357): at java.lang.Class.newInstance(Class.java:1409) E/AndroidRuntime(16357): at android.app.Instrumentation.newActivity(Instrumentation.java:1040) E/AndroidRuntime(16357): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1735) E/AndroidRuntime(16357): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1842) E/AndroidRuntime(16357): at android.app.ActivityThread.access$1500(ActivityThread.java:132) E/AndroidRuntime(16357): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1038) E/AndroidRuntime(16357): at android.os.Handler.dispatchMessage(Handler.java:99) E/AndroidRuntime(16357): at android.os.Looper.loop(Looper.java:143) E/AndroidRuntime(16357): at android.app.ActivityThread.main(ActivityThread.java:4263) E/AndroidRuntime(16357): at java.lang.reflect.Method.invokeNative(Native Method) E/AndroidRuntime(16357): at java.lang.reflect.Method.invoke(Method.java:507) E/AndroidRuntime(16357): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) E/AndroidRuntime(16357): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) E/AndroidRuntime(16357): at dalvik.system.NativeStart.main(Native Method)

    Read the article

  • Constructor or Explicit cast

    - by Felan
    In working with Linq to Sql I create a seperate class to ferry data to a web page. To simplify creating these ferry objects I either use a specialized constructor or an explicit conversion operator. I have two questions. First which approach is better from a readibility perspective? Second while the clr code that is generated appeared to be the same to me, are there situations where one would be treated different than the other by the compiler (in lambda's or such). Example code (DatabaseFoo uses specialized constructor and BusinessFoo uses explicit operator): public class DatabaseFoo { private static int idCounter; // just to help with generating data public int Id { get; set; } public string Name { get; set; } public DatabaseFoo() { Id = idCounter++; Name = string.Format("Test{0}", Id); } public DatabaseFoo(BusinessFoo foo) { this.Id = foo.Id; this.Name = foo.Name; } } public class BusinessFoo { public int Id { get; set; } public string Name { get; set; } public static explicit operator BusinessFoo(DatabaseFoo foo) { return FromDatabaseFoo(foo); } public static BusinessFoo FromDatabaseFoo(DatabaseFoo foo) { return new BusinessFoo {Id = foo.Id, Name = foo.Name}; } } public class Program { static void Main(string[] args) { Console.WriteLine("Creating the initial list of DatabaseFoo"); IEnumerable<DatabaseFoo> dafoos = new List<DatabaseFoo>() { new DatabaseFoo(), new DatabaseFoo(), new DatabaseFoo(), new DatabaseFoo(), new DatabaseFoo(), new DatabaseFoo()}; foreach(DatabaseFoo dafoo in dafoos) Console.WriteLine(string.Format("{0}\t{1}", dafoo.Id, dafoo.Name)); Console.WriteLine("Casting the list of DatabaseFoo to a list of BusinessFoo"); IEnumerable<BusinessFoo> bufoos = from x in dafoos select (BusinessFoo) x; foreach (BusinessFoo bufoo in bufoos) Console.WriteLine(string.Format("{0}\t{1}", bufoo.Id, bufoo.Name)); Console.WriteLine("Creating a new list of DatabaseFoo by calling the constructor taking BusinessFoo"); IEnumerable<DatabaseFoo> fufoos = from x in bufoos select new DatabaseFoo(x); foreach(DatabaseFoo fufoo in fufoos) Console.WriteLine(string.Format("{0}\t{1}", fufoo.Id, fufoo.Name)); } }

    Read the article

  • Java program has errors, 80 lines of code

    - by user2961687
    I have a problem with a program. It contains a lot of errors in Eclipse. Sorry for my english and thank you in advance. Here is the task: I. Declare a class that contains private fields Jam: String taste, double weight Create constructors containing variables as parameters: (String taste, double weight), (double weight), (String taste). Parameters constructors should initialize class fields. In case the constructor does not provide the necessary parameter, it must be assumed that the field taste must have the value "No Name" and weight - 100.0. Introduce the use of all constructors creating objects that represent three kinds of jams. Note: it must be assumed that the only constructor with two parameters can be assigned to fields of the class. Declare a class Jar that contains the field Jam jam, a dedicated constructor initiating all declared fields and methods: open close isItOpen Next, create an object of class Jar and fill it with the selected type of jam, operations repeat for all the kinds of jams. This is my code this far: public class App { public static void main(String[] args) { Jam strawberry = new Jam("strawberry", 20.45); Jam raspberry = new Jam(40.50); Jam peach = new Jam("peach"); Jar jar_1 = new Jar(); Jar jar_2 = new Jar(); Jar jar_3 = new Jar(); jar_1.open(); jar_1.fillIn(strawberry); jar_2.fillIn(peach); jar_3.fillIn(raspberry); } } class Jam { String taste; double weight; public Jam(String taste, double weight) { this.taste = taste; this.weight = weight; } public Jam(double weight) { this.taste = "No name"; this.weight = weight; } public Jam(String taste) { this.taste = taste; this.weight = 100.0; } } class Jar { public Jam Jam = new Jam(); private String state_jar; public Jar() { Jam.weight = 0; Jam.taste = ""; state_jar = "closed"; } public static String open() { state_jar = open; return state_jar; } public static String close() { state_jar = "closed"; return state_jar; } public static boolean isItOpen() { return state_jar; } public void fillIn(Jam jam) { if (isItOpen == false) open(); this.Jam.weight = jam.weight; this.Jam.taste = jam.taste; this.Jam.close(); } }

    Read the article

  • C array initialization.

    - by chrisdew
    Why does static char *opcode_str[] = { "DATA" , "DATA_REQUEST_ACK" , "ACK_TIMER_EXPIRED" , "ACK_UNEXPECTED_SEQ" , "ACK_AS_REQUESTED" } ; work, but static char **opcode_str = { "DATA" , "DATA_REQUEST_ACK" , "ACK_TIMER_EXPIRED" , "ACK_UNEXPECTED_SEQ" , "ACK_AS_REQUESTED" } ; fails with SEGV when opcode_str[0] is printf'd? I think it's because the second listing has not allocated memory for the five element array of pointers, but I need a more comprehensive explanation. All the best, Chris.

    Read the article

  • .NET Regex Instance Caching

    - by jvenema
    I've read this article, which describes how instance vs static methods get called with a .NET regex. However, what about if the instance itself is static? Does anyone know if .NET does any sort of caching that could potentially cause a memory leak?

    Read the article

  • RemoteViewsService never gets called whenever we update app widget

    - by user3689160
    I am making one task widget application. This is a simple widget application which can be used to add new tasks by clicking on "+New Task". So ideally what I have done is, I've added a widget first, then when we click on "+New Task" a new activity opens up from where we can type in a new task and it should get updated in the ListView inside the home screen widget. Problem: Now whenever I add a new task, the ListView does not get updated. The data gets inside the database a new is created as well. My onUpdate(...) method gets called as well. There is a WidgetService.java which is a RemoteViewService that is being used to call the RemoteViewFactory but WidgetService.java gets called only when we create the widget, never after that. WidgetService.java never gets called again. I have the following setup MyWidgetProvider.java AppWidgetProvider class for updating the widget and filling its remote views. public class MyWidgetProvider extends AppWidgetProvider { public static int randomNumber=132; static RemoteViews remoteViews = null; @Override public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { updateList(context,appWidgetManager,appWidgetIds); } public static void updateList(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds){ final int N = appWidgetIds.length; Log.d("MyWidgetProvider", "length="+appWidgetIds.length+""); for (int i = 0; i<N; ++i) { Log.d("MyWidgetProvider", "value"+ i + "="+appWidgetIds[i]); // Calling updateWidgetListView(context, appWidgetIds[i]); to load the listview with data remoteViews = updateWidgetListView(context, appWidgetIds[i]); // Updating the Widget with the new data filled remoteviews appWidgetManager.updateAppWidget(appWidgetIds[i], remoteViews); appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds[i], R.id.lv_tasks); } } private static RemoteViews updateWidgetListView(Context context, int appWidgetId) { Intent svcIntent = null; remoteViews = new RemoteViews(context.getPackageName(),R.layout.widget_demo); //RemoteViews Service needed to provide adapter for ListView svcIntent = new Intent(context, WidgetService.class); //passing app widget id to that RemoteViews Service svcIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId); //setting a unique Uri to the intent //binding the data from the WidgetService to the svcIntent svcIntent.setData(Uri.parse(svcIntent.toUri(Intent.URI_INTENT_SCHEME))); //setting adapter to listview of the widget remoteViews.setRemoteAdapter(R.id.lv_tasks, svcIntent); //setting click listner on the "New Task" (TextView) of the widget remoteViews.setOnClickPendingIntent(R.id.tv_add_task, buildButtonPendingIntent(context)); return remoteViews; } // Just to create PendingIntent, this will be broadcasted everytime textview containing "New Task" is clicked and OnReceive method of MyWidgetIntentReceiver.java will run public static PendingIntent buildButtonPendingIntent(Context context) { Intent intent = new Intent(); intent.putExtra("TASK_DONE_VALUE_VALID", false); intent.setAction("com.ommzi.intent.action.CLEARTASK"); return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT); } // This method is defined here so that we can update the remoteviews from other classes as well, like we'll do it in MyWidgetIntentReceiver.java public static void pushWidgetUpdate(Context context, RemoteViews remoteViews) { ComponentName myWidget = new ComponentName(context, MyWidgetProvider.class); AppWidgetManager manager = AppWidgetManager.getInstance(context); manager.updateAppWidget(myWidget, remoteViews); } } WidgetService.java A RemoteViewsService class for creating a RemoteViewsFactory. public class WidgetService extends RemoteViewsService { @Override public RemoteViewsFactory onGetViewFactory(Intent intent) { int appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID,AppWidgetManager.INVALID_APPWIDGET_ID); return (new ListProvider(this.getApplicationContext(), intent)); } } ListProvider.java A RemoteViewsFactory class for filling the ListView inside the widget. public class ListProvider implements RemoteViewsFactory { private List<TemplateTaskData> tasks; private Context context = null; private int appWidgetId; int increment=0; public ListProvider(Context context, Intent intent) { this.context = context; appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID,AppWidgetManager.INVALID_APPWIDGET_ID); //appWidgetId = Integer.valueOf(intent.getData().getSchemeSpecificPart())- MyWidgetProvider.randomNumber; populateListItem(); } private void populateListItem() { tasks = new ArrayList<TemplateTaskData>(); com.ommzi.database.sqliteDataBase letStartDB = new com.ommzi.database.sqliteDataBase(context); letStartDB.open(); tasks=letStartDB.getData(); letStartDB.close(); } public int getCount() { return tasks.size(); } public long getItemId(int position) { return position; } public RemoteViews getViewAt(int position) { // We are only showing the text view field here as there is limitation on using Checkbox within the widget // We prefer to on an activity for the user to make comprehensive changes as changes inside the widget is always limited. // To view the supported list of views for the widget you can visit http://developer.android.com/guide/topics/appwidgets/index.html final RemoteViews remoteView = new RemoteViews(context.getPackageName(), R.layout.screen_wcitem); TemplateTaskData taskDTO = tasks.get(position); Log.d("My ListProvider", "1"); remoteView.setTextViewText(R.id.wc_add_task, taskDTO.getTaskName()); if(taskDTO.getTaskDone()){ remoteView.setImageViewResource(R.id.imageView1, R.drawable.checked); }else{ remoteView.setImageViewResource(R.id.imageView1, R.drawable.unchecked); } Intent intent = new Intent(); intent.setAction("com.ommzi.intent.action.GETTASK"); intent.putExtra("TASK_DONE_VALUE_VALID", true); intent.putExtra("ROWID", taskDTO.getRowId()); intent.putExtra("TASK_NAME", taskDTO.getTaskName()); intent.putExtra("TASK_DONE_VALUE", taskDTO.getTaskDone()); remoteView.setOnClickPendingIntent(R.id.imageView1, PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)); Log.d("My ListProvider, Inside getView", "Value of Incrementor=" + increment + "\n ROWID=" + taskDTO.getRowId() + "\n TASK_NAME=" + taskDTO.getTaskName() + "\n TASK_DONE_VALUE=" +taskDTO.getTaskDone() + "\n Total Database Size=" + tasks.size()); return remoteView; } public RemoteViews getLoadingView() { // TODO Auto-generated method stub return null; } public int getViewTypeCount() { // TODO Auto-generated method stub return 1; } public boolean hasStableIds() { // TODO Auto-generated method stub return false; } public void onCreate() { // TODO Auto-generated method stub } public void onDataSetChanged() { // TODO Auto-generated method stub } public void onDestroy() { // TODO Auto-generated method stub } } GetTaskActivity.java This is another activity that is fired from a BroadcastReceiver(MyWidgetIntentReceiver.java). Purpose of this is to get a new task added to the list of task. MyWidgetIntentReceiver.java BroadcastReceiver fired using a pending intent that starts an activity GetTaskActivity.java. Please help me out with this problem. I am seen all the posts here and on other websites no body is having any solution. But I am sure a solution exist to this. Thanks for your help!

    Read the article

  • initializer not constant?

    - by fuzzygoat
    Quick question if I may: I am just curious about the following (see below) Xcode says "initializer element is not constant" why this does not work, I guess its the NSArray ... static NSArray *stuffyNames = [NSArray arrayWithObjects:@"Ted",@"Dog",@"Snosa",nil]; and this does ... static NSString *stuffyNames[3] = {@"Ted",@"Dog",@"Snosa"}; gary

    Read the article

  • Java: file write on finalize method

    - by sowrov
    In my understanding a singleton object will destroy only when the application is about to terminate. So in C++ I write a Singleton class to log my application and in that Singleton logger's destructor I log the time when my application was terminated. Things worked perfectly in C++. Now I want to have that same logger in Java, as in java there is no destructor so I implemented the finalize method for that singleton logger. But it seem that finalize method actually never get called. So, I add that System.runFinalizersOnExit(true); line, somewhere in my code (though I know it is deprecated) and that finalize method get called every time before termination of the app. But still there is a problem! If I try to write anything on file in that finalize method, It does not work, though System.out work without any problem! :( Can you guys help me on this problem? Here is a sample code of what I am try to do: Singleton Logger Class: public class MyLogger { FileWriter writer; private MyLogger() { try { this.writer = new FileWriter("log.txt"); } catch (IOException ex) { } } public static MyLogger getInstance() { return MyLoggerHolder.INSTANCE; } private static class MyLoggerHolder { private static final MyLogger INSTANCE = new MyLogger(); } @Override protected void finalize () { try { super.finalize(); System.out.println("Here"); //worked correctly. this.writer.write(new Date().toString()+System.getProperty("line.separator")); this.writer.write("End"); this.writer.flush(); //does not work! this.writer.close(); } catch (Throwable ex) { } } public synchronized void log(String str) { try { this.writer.write(new Date().toString()+System.getProperty("line.separator")); this.writer.write(str+"\n"); this.writer.flush(); } catch (IOException ex) { } } } Main: public class Main { public static void main(String[] args) { System.runFinalizersOnExit(true); MyLogger logger = MyLogger.getInstance(); logger.log("test"); } }

    Read the article

< Previous Page | 230 231 232 233 234 235 236 237 238 239 240 241  | Next Page >