Search Results

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

Page 195/832 | < Previous Page | 191 192 193 194 195 196 197 198 199 200 201 202  | Next Page >

• Oracle HRMS API – Update Employee Assignment

  - by PRajkumar

  To Update Supervisor, Manager Flag, Bargaining Unit, Labour Union Member Flag, Gre, Time Card, Work Schedule, Normal Hours, Frequency, Time Normal Finish, Time Normal Start, Default Code Combination, Set of Books Id API -- hr_assignment_api.update_emp_asg   To Update Grade, Location, Job, Payroll, Organization, Employee Category, People Group API -- hr_assignment_api.update_emp_asg_criteria   Example --   DECLARE    -- Local Variables    -- -----------------------    lc_dt_ud_mode           VARCHAR2(100)    := NULL;    ln_assignment_id       NUMBER                  := 33561;    ln_supervisor_id        NUMBER                  := 2;    ln_object_number       NUMBER                  := 1;    ln_people_group_id  NUMBER                  := 1;      -- Out Variables for Find Date Track Mode API    -- -----------------------------------------------------------------    lb_correction                           BOOLEAN;    lb_update                                 BOOLEAN;    lb_update_override              BOOLEAN;    lb_update_change_insert   BOOLEAN;       -- Out Variables for Update Employee Assignment API    -- ----------------------------------------------------------------------------    ln_soft_coding_keyflex_id       HR_SOFT_CODING_KEYFLEX.SOFT_CODING_KEYFLEX_ID%TYPE;    lc_concatenated_segments       VARCHAR2(2000);    ln_comment_id                             PER_ALL_ASSIGNMENTS_F.COMMENT_ID%TYPE;    lb_no_managers_warning        BOOLEAN;  -- Out Variables for Update Employee Assgment Criteria  -- -------------------------------------------------------------------------------  ln_special_ceiling_step_id                    PER_ALL_ASSIGNMENTS_F.SPECIAL_CEILING_STEP_ID%TYPE;  lc_group_name                                          VARCHAR2(30);  ld_effective_start_date                             PER_ALL_ASSIGNMENTS_F.EFFECTIVE_START_DATE%TYPE;  ld_effective_end_date                              PER_ALL_ASSIGNMENTS_F.EFFECTIVE_END_DATE%TYPE;  lb_org_now_no_manager_warning   BOOLEAN;  lb_other_manager_warning                  BOOLEAN;  lb_spp_delete_warning                          BOOLEAN;  lc_entries_changed_warning                VARCHAR2(30);  lb_tax_district_changed_warn             BOOLEAN;   BEGIN    -- Find Date Track Mode    -- --------------------------------    dt_api.find_dt_upd_modes    (    p_effective_date                  => TO_DATE('12-JUN-2011'),         p_base_table_name            => 'PER_ALL_ASSIGNMENTS_F',         p_base_key_column           => 'ASSIGNMENT_ID',         p_base_key_value               => ln_assignment_id,          -- Output data elements          -- --------------------------------          p_correction                          => lb_correction,          p_update                                => lb_update,          p_update_override              => lb_update_override,          p_update_change_insert   => lb_update_change_insert      );      IF ( lb_update_override = TRUE OR lb_update_change_insert = TRUE )    THEN        -- UPDATE_OVERRIDE        -- ---------------------------------        lc_dt_ud_mode := 'UPDATE_OVERRIDE';    END IF;     IF ( lb_correction = TRUE )   THEN       -- CORRECTION       -- ----------------------      lc_dt_ud_mode := 'CORRECTION';   END IF;     IF ( lb_update = TRUE )   THEN       -- UPDATE       -- --------------       lc_dt_ud_mode := 'UPDATE';    END IF;     -- Update Employee Assignment   -- ---------------------------------------------  hr_assignment_api.update_emp_asg  ( -- Input data elements   -- ------------------------------   p_effective_date                              => TO_DATE('12-JUN-2011'),   p_datetrack_update_mode         => lc_dt_ud_mode,   p_assignment_id                            => ln_assignment_id,   p_supervisor_id                              => NULL,   p_change_reason                           => NULL,   p_manager_flag                              => 'N',   p_bargaining_unit_code              => NULL,   p_labour_union_member_flag   => NULL,   p_segment1                                       => 204,   p_segment3                                       => 'N',   p_normal_hours                              => 10,   p_frequency                                       => 'W',   -- Output data elements   -- -------------------------------   p_object_version_number             => ln_object_number,   p_soft_coding_keyflex_id              => ln_soft_coding_keyflex_id,   p_concatenated_segments             => lc_concatenated_segments,   p_comment_id                                   => ln_comment_id,   p_effective_start_date                      => ld_effective_start_date,   p_effective_end_date                        => ld_effective_end_date,   p_no_managers_warning               => lb_no_managers_warning,   p_other_manager_warning            => lb_other_manager_warning  );    -- Find Date Track Mode for Second API   -- ------------------------------------------------------   dt_api.find_dt_upd_modes   (  p_effective_date                   => TO_DATE('12-JUN-2011'),      p_base_table_name            => 'PER_ALL_ASSIGNMENTS_F',      p_base_key_column           => 'ASSIGNMENT_ID',      p_base_key_value               => ln_assignment_id,      -- Output data elements      -- -------------------------------      p_correction                           => lb_correction,      p_update                                 => lb_update,      p_update_override               => lb_update_override,      p_update_change_insert    => lb_update_change_insert   );     IF ( lb_update_override = TRUE OR lb_update_change_insert = TRUE )   THEN     -- UPDATE_OVERRIDE     -- --------------------------------     lc_dt_ud_mode := 'UPDATE_OVERRIDE';   END IF;      IF ( lb_correction = TRUE )    THEN      -- CORRECTION      -- ----------------------      lc_dt_ud_mode := 'CORRECTION';   END IF;      IF ( lb_update = TRUE )    THEN      -- UPDATE      -- --------------      lc_dt_ud_mode := 'UPDATE';    END IF;    -- Update Employee Assgment Criteria  -- -----------------------------------------------------  hr_assignment_api.update_emp_asg_criteria  ( -- Input data elements   -- ------------------------------   p_effective_date                                   => TO_DATE('12-JUN-2011'),   p_datetrack_update_mode               => lc_dt_ud_mode,   p_assignment_id                                 => ln_assignment_id,   p_location_id                                        => 204,   p_grade_id                                             => 29,   p_job_id                                                  => 16,   p_payroll_id                                          => 52,   p_organization_id                               => 239,   p_employment_category                    => 'FR',   -- Output data elements   -- -------------------------------   p_people_group_id                              => ln_people_group_id,   p_object_version_number                   => ln_object_number,   p_special_ceiling_step_id                  => ln_special_ceiling_step_id,   p_group_name                                        => lc_group_name,   p_effective_start_date                           => ld_effective_start_date,   p_effective_end_date                             => ld_effective_end_date,   p_org_now_no_manager_warning  => lb_org_now_no_manager_warning,   p_other_manager_warning                 => lb_other_manager_warning,   p_spp_delete_warning                         => lb_spp_delete_warning,   p_entries_changed_warning              => lc_entries_changed_warning,   p_tax_district_changed_warning     => lb_tax_district_changed_warn  );    COMMIT; EXCEPTION          WHEN OTHERS THEN                       ROLLBACK;                       dbms_output.put_line(SQLERRM); END; / SHOW ERR;    

  Read the article

• Java Array Index Out of Bounds Exception

  - by user1302023

  I need help debugging the following program: I'm getting a run time error that reads: Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: -1 at SearchEngine.main(SearchEngine.java:126) import java.util.*; import java.io.*; public class SearchEngine { public static int getNumberOfWords (File f) throws FileNotFoundException { int numWords = 0; Scanner scan = new Scanner(f); while (scan.hasNext()) { numWords++; scan.next(); } scan.close(); return numWords; } public static void readInWords (File input, String [] x) throws FileNotFoundException { Scanner scan = new Scanner(input); int i = 0; while (scan.hasNext() && i<x.length) { x[i] = scan.next(); i++; } scan.close(); } public static int getNumOfDistinctWords (File input, String [] x) throws FileNotFoundException { Scanner scan = new Scanner(input); int count = 0; int i = 1; while (scan.hasNext() && i<x.length) { if (!x[i].equals(x[i-1])) { count++; } i++; } scan.close(); return count; } public static void readInDistinctWords (String [] x, String [] y) { int i = 1; int k = 0; while (i<x.length) { if (!x[i].equals(x[i-1])) { y[k] = x[i]; k++; } i++; } } public static int getNumberOfLines (File input) throws FileNotFoundException { int numLines = 0; Scanner scan = new Scanner(input); while (scan.hasNextLine()) { numLines++; scan.nextLine(); } scan.close(); return numLines; } public static void readInLines (File input, String [] x) throws FileNotFoundException { Scanner scan = new Scanner(input); int i = 0; while (scan.hasNextLine() && i<x.length) { x[i] = scan.nextLine(); i++; } scan.close(); } public static void main(String [] args) { try { //gets file name System.out.println("Enter the name of the text file you wish to search"); Scanner kb = new Scanner(System.in); String fileName = kb.nextLine(); String TXT = ".txt"; if (!fileName.endsWith(TXT)) { fileName = fileName.concat(TXT); } File input = new File(fileName); //First part of creating index System.out.println("Creating vocabArray"); int NUM_WORDS = getNumberOfWords(input); //System.out.println(NUM_WORDS); String [] wordArray = new String[NUM_WORDS]; readInWords(input, wordArray); Arrays.sort(wordArray); int NUM_DISTINCT_WORDS = getNumOfDistinctWords(input, wordArray); String [] vocabArray = new String[NUM_DISTINCT_WORDS]; readInDistinctWords(wordArray, vocabArray); System.out.println("Finished creating vocabArray"); System.out.println("Creating concordanceArray"); int NUM_LINES = getNumberOfLines(input); String [] concordanceArray = new String[NUM_LINES]; readInLines(input, concordanceArray); System.out.println("Finished creating concordanceArray"); System.out.println("Creating invertedIndex"); int [][] invertedIndex = new int[NUM_DISTINCT_WORDS][10]; int [] wordCountArray = new int[NUM_DISTINCT_WORDS]; int lineNum = 0; while (lineNum<concordanceArray.length) { Scanner scan = new Scanner(concordanceArray[lineNum]); while (scan.hasNext()) { int wordPos = Arrays.binarySearch(vocabArray, scan.next()); wordCountArray[wordPos]+=1; for(int i = 0; i < invertedIndex.length; i++) { for(int j = 0; j < invertedIndex[i].length; j++) { if (invertedIndex[i][j] == 0) { invertedIndex[i][j] = lineNum; break; } } } } lineNum++; } System.out.println("Finished creating invertedIndex"); } catch (FileNotFoundException exception) { System.out.println("File Not Found"); } } //main } //class

  Read the article

• How to give position zero of spinner a prompt value?

  - by Eugene H

  The database is then transferring the data to a spinner which I want to leave position 0 blank so I can add a item to the spinner with no value making it look like a prompt. I have been going at it all day. FAil after Fail MainActivity public class MainActivity extends Activity { Button AddBtn; EditText et; EditText cal; Spinner spn; SQLController SQLcon; ProgressDialog PD; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); AddBtn = (Button) findViewById(R.id.addbtn_id); et = (EditText) findViewById(R.id.et_id); cal = (EditText) findViewById(R.id.et_cal); spn = (Spinner) findViewById(R.id.spinner_id); spn.setOnItemSelectedListener(new OnItemSelectedListenerWrapper( new OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) { SQLcon.open(); Cursor c = SQLcon.readData(); if (c.moveToPosition(pos)) { String name = c.getString(c .getColumnIndex(DBhelper.MEMBER_NAME)); String calories = c.getString(c .getColumnIndex(DBhelper.KEY_CALORIES)); et.setText(name); cal.setText(calories); } SQLcon.close(); // closing database } @Override public void onNothingSelected(AdapterView<?> parent) { // TODO Auto-generated method stub } })); SQLcon = new SQLController(this); // opening database SQLcon.open(); loadtospinner(); AddBtn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { new MyAsync().execute(); } }); } public void loadtospinner() { ArrayList<String> al = new ArrayList<String>(); Cursor c = SQLcon.readData(); c.moveToFirst(); while (!c.isAfterLast()) { String name = c.getString(c.getColumnIndex(DBhelper.MEMBER_NAME)); String calories = c.getString(c .getColumnIndex(DBhelper.KEY_CALORIES)); al.add(name + ", Calories: " + calories); c.moveToNext(); } ArrayAdapter<String> aa1 = new ArrayAdapter<String>( getApplicationContext(), android.R.layout.simple_spinner_item, al); spn.setAdapter(aa1); // closing database SQLcon.close(); } private class MyAsync extends AsyncTask<Void, Void, Void> { @Override protected void onPreExecute() { super.onPreExecute(); PD = new ProgressDialog(MainActivity.this); PD.setTitle("Please Wait.."); PD.setMessage("Loading..."); PD.setCancelable(false); PD.show(); } @Override protected Void doInBackground(Void... params) { String name = et.getText().toString(); String calories = cal.getText().toString(); // opening database SQLcon.open(); // insert data into table SQLcon.insertData(name, calories); return null; } @Override protected void onPostExecute(Void result) { super.onPostExecute(result); loadtospinner(); PD.dismiss(); } } } DataBase public class SQLController { private DBhelper dbhelper; private Context ourcontext; private SQLiteDatabase database; public SQLController(Context c) { ourcontext = c; } public SQLController open() throws SQLException { dbhelper = new DBhelper(ourcontext); database = dbhelper.getWritableDatabase(); return this; } public void close() { dbhelper.close(); } public void insertData(String name, String calories) { ContentValues cv = new ContentValues(); cv.put(DBhelper.MEMBER_NAME, name); cv.put(DBhelper.KEY_CALORIES, calories); database.insert(DBhelper.TABLE_MEMBER, null, cv); } public Cursor readData() { String[] allColumns = new String[] { DBhelper.MEMBER_ID, DBhelper.MEMBER_NAME, DBhelper.KEY_CALORIES }; Cursor c = database.query(DBhelper.TABLE_MEMBER, allColumns, null, null, null, null, null); if (c != null) { c.moveToFirst(); } return c; } } Helper public class DBhelper extends SQLiteOpenHelper { // TABLE INFORMATTION public static final String TABLE_MEMBER = "member"; public static final String MEMBER_ID = "_id"; public static final String MEMBER_NAME = "name"; public static final String KEY_CALORIES = "calories"; // DATABASE INFORMATION static final String DB_NAME = "MEMBER.DB"; static final int DB_VERSION = 2; // TABLE CREATION STATEMENT private static final String CREATE_TABLE = "create table " + TABLE_MEMBER + "(" + MEMBER_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + MEMBER_NAME + " TEXT NOT NULL," + KEY_CALORIES + " INT NOT NULL);"; public DBhelper(Context context) { super(context, DB_NAME, null, DB_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_TABLE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO Auto-generated method stub db.execSQL("DROP TABLE IF EXISTS " + TABLE_MEMBER); onCreate(db); } }

  Read the article

• SOA 10g Developing a Simple Hello World Process

  - by [email protected]

  Softwares & Hardware Needed Intel Pentium D CPU 3 GHz, 2 GB RAM, Windows XP System ( Thats what i am using ) You could as well use Linux , but please choose High End RAM 10G SOA Suite from Oracle(TM) , Read Installation documents at www.Oracle.com J Developer 10.1.3.3 Official Documents at http://www.oracle.com/technology/products/ias/bpel/index.html java -version Java HotSpot(TM) Client VM (build 1.5.0_06-b05, mixed mode)BPEL Introduction - Developing a Simple Hello World Process  Synchronous BPEL Process      This Exercise focuses on developing a Synchronous Process, which mean you give input to the BPEL Process you get output immediately no waiting at all. The Objective of this exercise is to give input as name and it greets with Hello Appended by that name example, if I give input as "James" the BPEL process returns "Hello James". 1. Open the Oracle JDeveloper click on File -> New Application give the name "JamesApp" you can give your own name if it pleases you. Select the folder where you want to place the application. Click "OK" 2. Right Click on the "JamesApp" in the Application Navigator, Select New Menu. 3. Select "Projects" under "General" and "BPEL Process Project", click "OK" these steps remain same for all BPEL Projects 4. Project Setting Wizard Appears, Give the "Process Name" as "MyBPELProc" and Namespace as http://xmlns.james.com/ MyBPELProc, Select Template as "Synchronous BPEL Process click "Next" 5. Accept the input and output schema names as it is, click "Finish" 6. You would see the BPEL Process Designer, some of the folders such as Integration content and Resources are created and few more files 7. Assign Activity : Allows Assigning values to variables or copying values of one variable to another and also do some string manipulation or mathematical operations In the component palette at extreme right, select Process Activities from the drop down, and drag and drop "Assign" between "receive Input" and "replyOutput" 8. You can right click and edit the Assign activity and give any suitable name "AssignHello", 9. Select "Copy Operation" Tab create "Copy Operation" 10. In the From variables click on expression builder, select input under "input variable", Click on insert into expression bar, complete the concat syntax, Note to use "Ctrl+space bar" inside expression window to Auto Populate the expression as shown in the figure below. What we are actually doing here is concatenating the String "Hello ", with the variable value received through the variable named "input" 11. Observe that once an expression is completed the "To Variable" is assigned to a variable by name "result" 12. Finally the copy variable looks as below 13. It's the time to deploy, start the SOA Suite 14. Establish connection to the Server from JDeveloper, this can be done adding a New Application Server under Connection, give the server name, username and password and test connection. 15. Deploy the "MyBPELProc" to the "default domain" 16. http://localhost:8080/ allows connecting to SOA Suite web portal, click on "BPEL Control" , login with the username "oc4jadmin" password what ever you gave during installation 17. "MyBPELProc" is visisble under "Deployed BPEL Processes" in the "Dashboard" Tab, click on the it 18. Initiate tab open to accept input, enter data such as input is "James" click on "Post XML Button" 19. Click on Visual Flow 20. Click on receive Input , it shows "James" as input received 21. Click on reply Output, it shows "Hello James" so the BPEL process is successfully executed. 22. It may be worth seeing all the instance created everytime a BPEL process is executed by giving some inputs. Purge All button allows to delete all the unwanted previous instances of BPEL process, dont worry it wont delete the BPEL process itself :-) 23. It may also be some importance to understand the XSD File which holds input & output variable names & data types. 24. You could drag n drop variables as elements over sequence at the designer or directly edit the XML Source file. 

  Read the article

• T-SQL Improvements And Data Types in ms sql 2008

  - by Aamir Hasan

   Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

  Read the article

• Thread Synchronization and Synchronization Primitives

  When considering synchronization in an application, the decision truly depends on what the application and its worker threads are going to do. I would use synchronization if two or more threads could possibly manipulate the same instance of an object at the same time. An example of this in C# can be demonstrated through the use of storing data in a static object. A static object is initialized once per application and the data within the object can be accessed by all threads. I would use the synchronization primitives to prevent any data from being manipulated by multiple threads simultaneously. This would reduce any data corruption from occurring within the object. On the other hand if all the threads used non static objects and were independent of the other tasks there would be no need to use synchronization. Synchronization Primitives in C#: Basic Blocking Locking Signaling Non-Blocking Synchronization Constructs The Basic Blocking methods include Sleep, Join, and Task.Wait.  These methods force threads to wait until other threads have completed. In addition, these methods can also force a thread to wait a set amount of time before continuing to work.   The Locking primitive prevents a thread from entering a critical section of code while another thread is in the same critical section.  If another thread attempts to enter a locked code, it will wait, until the code block is released. The Signaling primitive allows a thread to temporarily pause work until receiving a notification from another thread that it is ok to continue working. The Signaling primitive removes the need for polling.The Non-Blocking Synchronization Constructs protect access to a common field by calling upon processor primitives.

  Read the article

• Revisiting ANTS Performance Profiler 7.4

  - by James Michael Hare

  Last year, I did a small review on the ANTS Performance Profiler 6.3, now that it’s a year later and a major version number higher, I thought I’d revisit the review and revise my last post. This post will take the same examples as the original post and update them to show what’s new in version 7.4 of the profiler. Background A performance profiler’s main job is to keep track of how much time is typically spent in each unit of code. This helps when we have a program that is not running at the performance we expect, and we want to know where the program is experiencing issues. There are many profilers out there of varying capabilities. Red Gate’s typically seem to be the very easy to “jump in” and get started with very little training required. So let’s dig into the Performance Profiler. I’ve constructed a very crude program with some obvious inefficiencies. It’s a simple program that generates random order numbers (or really could be any unique identifier), adds it to a list, sorts the list, then finds the max and min number in the list. Ignore the fact it’s very contrived and obviously inefficient, we just want to use it as an example to show off the tool: 1: // our test program 2: public static class Program 3: { 4: // the number of iterations to perform 5: private static int _iterations = 1000000; 6: 7: // The main method that controls it all 8: public static void Main() 9: { 10: var list = new List<string>(); 11: 12: for (int i = 0; i < _iterations; i++) 13: { 14: var x = GetNextId(); 15: 16: AddToList(list, x); 17: 18: var highLow = GetHighLow(list); 19: 20: if ((i % 1000) == 0) 21: { 22: Console.WriteLine("{0} - High: {1}, Low: {2}", i, highLow.Item1, highLow.Item2); 23: Console.Out.Flush(); 24: } 25: } 26: } 27: 28: // gets the next order id to process (random for us) 29: public static string GetNextId() 30: { 31: var random = new Random(); 32: var num = random.Next(1000000, 9999999); 33: return num.ToString(); 34: } 35: 36: // add it to our list - very inefficiently! 37: public static void AddToList(List<string> list, string item) 38: { 39: list.Add(item); 40: list.Sort(); 41: } 42: 43: // get high and low of order id range - very inefficiently! 44: public static Tuple<int,int> GetHighLow(List<string> list) 45: { 46: return Tuple.Create(list.Max(s => Convert.ToInt32(s)), list.Min(s => Convert.ToInt32(s))); 47: } 48: } So let’s run it through the profiler and see what happens! Visual Studio Integration First, let’s look at how the ANTS profilers integrate with Visual Studio’s menu system. Once you install the ANTS profilers, you will get an ANTS menu item with several options: Notice that you can either Profile Performance or Launch ANTS Performance Profiler. These sound similar but achieve two slightly different actions: Profile Performance: this immediately launches the profiler with all defaults selected to profile the active project in Visual Studio. Launch ANTS Performance Profiler: this launches the profiler much the same way as starting it from the Start Menu. The profiler will pre-populate the application and path information, but allow you to change the settings before beginning the profile run. So really, the main difference is that Profile Performance immediately begins profiling with the default selections, where Launch ANTS Performance Profiler allows you to change the defaults and attach to an already-running application. Let’s Fire it Up! So when you fire up ANTS either via Start Menu or Launch ANTS Performance Profiler menu in Visual Studio, you are presented with a very simple dialog to get you started: Notice you can choose from many different options for application type. You can profile executables, services, web applications, or just attach to a running process. In fact, in version 7.4 we see two new options added: ASP.NET Web Application (IIS Express) SharePoint web application (IIS) So this gives us an additional way to profile ASP.NET applications and the ability to profile SharePoint applications as well. You can also choose your level of detail in the Profiling Mode drop down. If you choose Line-Level and method-level timings detail, you will get a lot more detail on the method durations, but this will also slow down profiling somewhat. If you really need the profiler to be as unintrusive as possible, you can change it to Sample method-level timings. This is performing very light profiling, where basically the profiler collects timings of a method by examining the call-stack at given intervals. Which method you choose depends a lot on how much detail you need to find the issue and how sensitive your program issues are to timing. So for our example, let’s just go with the line and method timing detail. So, we check that all the options are correct (if you launch from VS2010, the executable and path are filled in already), and fire it up by clicking the [Start Profiling] button. Profiling the Application Once you start profiling the application, you will see a real-time graph of CPU usage that will indicate how much your application is using the CPU(s) on your system. During this time, you can select segments of the graph and bookmark them, giving them mnemonic names. This can be useful if you want to compare performance in one part of the run to another part of the run. Notice that once you select a block, it will give you the call tree breakdown for that selection only, and the relative performance of those calls. Once you feel you have collected enough information, you can click [Stop Profiling] to stop the application run and information collection and begin a more thorough analysis. Analyzing Method Timings So now that we’ve halted the run, we can look around the GUI and see what we can see. By default, the times are shown in terms of percentage of time of the total run of the application, though you can change it in the View menu item to milliseconds, ticks, or seconds as well. This won’t affect the percentages of methods, it only affects what units the times are shown. Notice also that the major hotspot seems to be in a method without source, ANTS Profiler will filter these out by default, but you can right-click on the line and remove the filter to see more detail. This proves especially handy when a bottleneck is due to a method in the BCL. So now that we’ve removed the filter, we see a bit more detail: In addition, ANTS Performance Profiler gives you the ability to decompile the methods without source so that you can dive even deeper, though typically this isn’t necessary for our purposes. When looking at timings, there are generally two types of timings for each method call: Time: This is the time spent ONLY in this method, not including calls this method makes to other methods. Time With Children: This is the total of time spent in both this method AND including calls this method makes to other methods. In other words, the Time tells you how much work is being done exclusively in this method, and the Time With Children tells you how much work is being done inclusively in this method and everything it calls. You can also choose to display the methods in a tree or in a grid. The tree view is the default and it shows the method calls arranged in terms of the tree representing all method calls and the parent method that called them, etc. This is useful for when you find a hot-spot method, you can see who is calling it to determine if the problem is the method itself, or if it is being called too many times. The grid method represents each method only once with its totals and is useful for quickly seeing what method is the trouble spot. In addition, you can choose to display Methods with source which are generally the methods you wrote (as opposed to native or BCL code), or Any Method which shows not only your methods, but also native calls, JIT overhead, synchronization waits, etc. So these are just two ways of viewing the same data, and you’re free to choose the organization that best suits what information you are after. Analyzing Method Source If we look at the timings above, we see that our AddToList() method (and in particular, it’s call to the List<T>.Sort() method in the BCL) is the hot-spot in this analysis. If ANTS sees a method that is consuming the most time, it will flag it as a hot-spot to help call out potential areas of concern. This doesn’t mean the other statistics aren’t meaningful, but that the hot-spot is most likely going to be your biggest bang-for-the-buck to concentrate on. So let’s select the AddToList() method, and see what it shows in the source window below: Notice the source breakout in the bottom pane when you select a method (from either tree or grid view). This shows you the timings in this method per line of code. This gives you a major indicator of where the trouble-spot in this method is. So in this case, we see that performing a Sort() on the List<T> after every Add() is killing our performance! Of course, this was a very contrived, duh moment, but you’d be surprised how many performance issues become duh moments. Note that this one line is taking up 86% of the execution time of this application! If we eliminate this bottleneck, we should see drastic improvement in the performance. So to fix this, if we still wanted to maintain the List<T> we’d have many options, including: delay Sort() until after all Add() methods, using a SortedSet, SortedList, or SortedDictionary depending on which is most appropriate, or forgoing the sorting all together and using a Dictionary. Rinse, Repeat! So let’s just change all instances of List<string> to SortedSet<string> and run this again through the profiler: Now we see the AddToList() method is no longer our hot-spot, but now the Max() and Min() calls are! This is good because we’ve eliminated one hot-spot and now we can try to correct this one as well. As before, we can then optimize this part of the code (possibly by taking advantage of the fact the list is now sorted and returning the first and last elements). We can then rinse and repeat this process until we have eliminated as many bottlenecks as possible. Calls by Web Request Another feature that was added recently is the ability to view .NET methods grouped by the HTTP requests that caused them to run. This can be helpful in determining which pages, web services, etc. are causing hot spots in your web applications. Summary If you like the other ANTS tools, you’ll like the ANTS Performance Profiler as well. It is extremely easy to use with very little product knowledge required to get up and running. There are profilers built into the higher product lines of Visual Studio, of course, which are also powerful and easy to use. But for quickly jumping in and finding hot spots rapidly, Red Gate’s Performance Profiler 7.4 is an excellent choice. Technorati Tags: Influencers,ANTS,Performance Profiler,Profiler

  Read the article

• STUN-server using AWS

  - by Yrlec

  We are about to hire some consultants to help us set up an AWS-based server environment that will enable us to handle NAT Traversal for our P2P application. One important part of the NAT Traversal infrastructure is the STUN-server (http://en.wikipedia.org/wiki/STUN). They just told us that in order for the STUN-server to work you must have two public static IP-addresses pointing to the same server. To more specific they said this: It appears that you need 2 static IPs for each server for the STUN to work. Please note, these IPs have to be put into the configuration file, therefore, each time you restart the instance you have to make sure you either use the same IPs or you have to update configuration. As you plan to use AWS for your installation, please confirm that you can have 2 static IP for each server. Our question is if this is possible using AWS and if so, how? If not, do you know any other way to set up a STUN-server using AWS?

  Read the article

• Linux: setting up an elite/high-anonimity Web proxy on a dedicated server

  - by YellowSquirrel

  I'm renting a dedicated server which I'd like to use to "surf the Web": basically I want to always surf the Web from the same static IP (the one of my dedicated server). I can do it by running Xvnc/FreeNX on the dedicated server, but this is kinda slow and clumsy (I tried it). What are the steps needed to install an "elite/high-anonimity" Web proxy on a dedicated (Debian) Linux server knowing that my two requirements are: I'm the only person that needs access to the proxy all I want is that my broadband (dynamic) IP is completely hidden (I want to always surf from my dedicated server's IP). Note that using the static IP people can find my domains and my real name and I'm perfectly fine with that (actually it is what I want). What I don't want is people knowing from which dynamic IP (broadband) I'm connecting. What are the steps needed to do that? (basically I don't care about "anonimity", what I want is to appear to surf from a static IP and I think I need what is called an "elite" Web proxy to do that, but I'm not sure) Technical infos and sample configuration most welcome :)

  Read the article

• Connect ViewModel and View using Unity

  - by brainbox

  In this post i want to describe the approach of connecting View and ViewModel which I'm using in my last project.The main idea is to do it during resolve inside of unity container. It can be achived using InjectionFactory introduced in Unity 2.0 public static class MVVMUnityExtensions{    public static void RegisterView<TView, TViewModel>(this IUnityContainer container) where TView : FrameworkElement    {        container.RegisterView<TView, TView, TViewModel>();    }    public static void RegisterView<TViewFrom, TViewTo, TViewModel>(this IUnityContainer container)        where TViewTo : FrameworkElement, TViewFrom    {        container.RegisterType<TViewFrom>(new InjectionFactory(            c =>            {                var model = c.Resolve<TViewModel>();                var view = Activator.CreateInstance<TViewTo>();                view.DataContext = model;                return view;            }         ));    }}}And here is the sample how it could be used:var unityContainer = new UnityContainer();unityContainer.RegisterView<IFooView, FooView, FooViewModel>();IFooView view = unityContainer.Resolve<IFooView>(); // view with injected viewmodel in its datacontextPlease tell me your prefered way to connect viewmodel and view.

  Read the article

• Dual Nic, one keeps dropping

  - by user1215018

  I'm running windows server 2008 r2 on a dell poweredge 2850. I have 2 NICs, one is configured behind a firewall with a dhcp server on the main local LAN and another one has it's own dedicated connection to one of our 13 static IPs. So in a nutshell we have 2 of our static IPs going to this server, one indirectly through a firewall/dhcp server, and the other directly. I am trying to reach IIS on port 80 and port 443. The problem is that the NIC with the direct connection (NIC2) keeps dropping and says either "No internet connection" or "Unauthenticated". However, the NIC behind the firewall (NIC1) has no problems at all. Update: This is the second time this has happened in 3 days and each time the fix has been enabling the dhcp client on the NIC, allowing it to error out to a 169.x.x.x address, then re-enabling the nic with it's static IP assignment.

  Read the article

• DocumentDB - Another Azure NoSQL Storage Service

  - by Shaun

  Originally posted on: http://geekswithblogs.net/shaunxu/archive/2014/08/25/documentdb---another-azure-nosql-storage-service.aspxMicrosoft just released a bunch of new features for Azure on 22nd and one of them I was interested in most is DocumentDB, a document NoSQL database service on the cloud.   Quick Look at DocumentDB We can try DocumentDB from the new azure preview portal. Just click the NEW button and select the item named DocumentDB to create a new account. Specify the name of the DocumentDB, which will be the endpoint we are going to use to connect later. Select the capacity unit, resource group and subscription. In resource group section we can select which region our DocumentDB will be located. Same as other azure services select the same location with your consumers of the DocumentDB, for example the website, web services, etc.. After several minutes the DocumentDB will be ready. Click the KEYS button we can find the URI and primary key, which will be used when connecting. Now let's open Visual Studio and try to use the DocumentDB we had just created. Create a new console application and install the DocumentDB .NET client library from NuGet with the keyword "DocumentDB". You need to select "Include Prerelase" in NuGet Package Manager window since this library was not yet released. Next we will create a new database and document collection under our DocumentDB account. The code below created an instance of DocumentClient with the URI and primary key we just copied from azure portal, and create a database and collection. And it also prints the document and collection link string which will be used later to insert and query documents. 1: static void Main(string[] args) 2: { 3: var endpoint = new Uri("https://shx.documents.azure.com:443/"); 4: var key = "LU2NoyS2fH0131TGxtBE4DW/CjHQBzAaUx/mbuJ1X77C4FWUG129wWk2oyS2odgkFO2Xdif9/ZddintQicF+lA=="; 5:  6: var client = new DocumentClient(endpoint, key); 7: Run(client).Wait(); 8:  9: Console.WriteLine("done"); 10: Console.ReadKey(); 11: } 12:  13: static async Task Run(DocumentClient client) 14: { 15:  16: var database = new Database() { Id = "testdb" }; 17: database = await client.CreateDatabaseAsync(database); 18: Console.WriteLine("database link = {0}", database.SelfLink); 19:  20: var collection = new DocumentCollection() { Id = "testcol" }; 21: collection = await client.CreateDocumentCollectionAsync(database.SelfLink, collection); 22: Console.WriteLine("collection link = {0}", collection.SelfLink); 23: } Below is the result from the console window. We need to copy the collection link string for future usage. Now if we back to the portal we will find a database was listed with the name we specified in the code. Next we will insert a document into the database and collection we had just created. In the code below we pasted the collection link which copied in previous step, create a dynamic object with several properties defined. As you can see we can add some normal properties contains string, integer, we can also add complex property for example an array, a dictionary and an object reference, unless they can be serialized to JSON. 1: static void Main(string[] args) 2: { 3: var endpoint = new Uri("https://shx.documents.azure.com:443/"); 4: var key = "LU2NoyS2fH0131TGxtBE4DW/CjHQBzAaUx/mbuJ1X77C4FWUG129wWk2oyS2odgkFO2Xdif9/ZddintQicF+lA=="; 5:  6: var client = new DocumentClient(endpoint, key); 7:  8: // collection link pasted from the result in previous demo 9: var collectionLink = "dbs/AAk3AA==/colls/AAk3AP6oFgA=/"; 10:  11: // document we are going to insert to database 12: dynamic doc = new ExpandoObject(); 13: doc.firstName = "Shaun"; 14: doc.lastName = "Xu"; 15: doc.roles = new string[] { "developer", "trainer", "presenter", "father" }; 16:  17: // insert the docuemnt 18: InsertADoc(client, collectionLink, doc).Wait(); 19:  20: Console.WriteLine("done"); 21: Console.ReadKey(); 22: } the insert code will be very simple as below, just provide the collection link and the object we are going to insert. 1: static async Task InsertADoc(DocumentClient client, string collectionLink, dynamic doc) 2: { 3: var document = await client.CreateDocumentAsync(collectionLink, doc); 4: Console.WriteLine(await JsonConvert.SerializeObjectAsync(document, Formatting.Indented)); 5: } Below is the result after the object had been inserted. Finally we will query the document from the database and collection. Similar to the insert code, we just need to specify the collection link so that the .NET SDK will help us to retrieve all documents in it. 1: static void Main(string[] args) 2: { 3: var endpoint = new Uri("https://shx.documents.azure.com:443/"); 4: var key = "LU2NoyS2fH0131TGxtBE4DW/CjHQBzAaUx/mbuJ1X77C4FWUG129wWk2oyS2odgkFO2Xdif9/ZddintQicF+lA=="; 5:  6: var client = new DocumentClient(endpoint, key); 7:  8: var collectionLink = "dbs/AAk3AA==/colls/AAk3AP6oFgA=/"; 9:  10: SelectDocs(client, collectionLink); 11:  12: Console.WriteLine("done"); 13: Console.ReadKey(); 14: } 15:  16: static void SelectDocs(DocumentClient client, string collectionLink) 17: { 18: var docs = client.CreateDocumentQuery(collectionLink + "docs/").ToList(); 19: foreach(var doc in docs) 20: { 21: Console.WriteLine(doc); 22: } 23: } Since there's only one document in my collection below is the result when I executed the code. As you can see all properties, includes the array was retrieve at the same time. DocumentDB also attached some properties we didn't specified such as "_rid", "_ts", "_self" etc., which is controlled by the service.   DocumentDB Benefit DocumentDB is a document NoSQL database service. Different from the traditional database, document database is truly schema-free. In a short nut, you can save anything in the same database and collection if it could be serialized to JSON. We you query the document database, all sub documents will be retrieved at the same time. This means you don't need to join other tables when using a traditional database. Document database is very useful when we build some high performance system with hierarchical data structure. For example, assuming we need to build a blog system, there will be many blog posts and each of them contains the content and comments. The comment can be commented as well. If we were using traditional database, let's say SQL Server, the database schema might be defined as below. When we need to display a post we need to load the post content from the Posts table, as well as the comments from the Comments table. We also need to build the comment tree based on the CommentID field. But if were using DocumentDB, what we need to do is to save the post as a document with a list contains all comments. Under a comment all sub comments will be a list in it. When we display this post we just need to to query the post document, the content and all comments will be loaded in proper structure. 1: { 2: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 3: "title": "xxxxx", 4: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 5: "postedOn": "08/25/2014 13:55", 6: "comments": 7: [ 8: { 9: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 10: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 11: "commentedOn": "08/25/2014 14:00", 12: "commentedBy": "xxx" 13: }, 14: { 15: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 16: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 17: "commentedOn": "08/25/2014 14:10", 18: "commentedBy": "xxx", 19: "comments": 20: [ 21: { 22: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 23: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 24: "commentedOn": "08/25/2014 14:18", 25: "commentedBy": "xxx", 26: "comments": 27: [ 28: { 29: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 30: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 31: "commentedOn": "08/25/2014 18:22", 32: "commentedBy": "xxx", 33: } 34: ] 35: }, 36: { 37: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 38: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 39: "commentedOn": "08/25/2014 15:02", 40: "commentedBy": "xxx", 41: } 42: ] 43: }, 44: { 45: "id": "xxxxx-xxxxx-xxxxx-xxxxx", 46: "content": "xxxxx, xxxxxxxxx. xxxxxx, xx, xxxx.", 47: "commentedOn": "08/25/2014 14:30", 48: "commentedBy": "xxx" 49: } 50: ] 51: }   DocumentDB vs. Table Storage DocumentDB and Table Storage are all NoSQL service in Microsoft Azure. One common question is "when we should use DocumentDB rather than Table Storage". Here are some ideas from me and some MVPs. First of all, they are different kind of NoSQL database. DocumentDB is a document database while table storage is a key-value database. Second, table storage is cheaper. DocumentDB supports scale out from one capacity unit to 5 in preview period and each capacity unit provides 10GB local SSD storage. The price is $0.73/day includes 50% discount. For storage service the highest price is $0.061/GB, which is almost 10% of DocumentDB. Third, table storage provides local-replication, geo-replication, read access geo-replication while DocumentDB doesn't support. Fourth, there is local emulator for table storage but none for DocumentDB. We have to connect to the DocumentDB on cloud when developing locally. But, DocumentDB supports some cool features that table storage doesn't have. It supports store procedure, trigger and user-defined-function. It supports rich indexing while table storage only supports indexing against partition key and row key. It supports transaction, table storage supports as well but restricted with Entity Group Transaction scope. And the last, table storage is GA but DocumentDB is still in preview.   Summary In this post I have a quick demonstration and introduction about the new DocumentDB service in Azure. It's very easy to interact through .NET and it also support REST API, Node.js SDK and Python SDK. Then I explained the concept and benefit of  using document database, then compared with table storage.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

  Read the article

• Django Dying on Shared Hosting Environment (Too Many MySQL Connections)

  - by Tom

  I've had a Django site up and running on HostGator (client requirement), following these instructions, for a few weeks now. I had seen two error emails about pages dying with (1040: Too many MySQL connections) but had never been able to recreate the problem. As of today, the site is completely unresponsive and all pages, even the static files, are dying with that error. Two questions: What can I do to fix this (other than caching more stuff)? Why would static files be dying like that? I can request them directly without a problem, so how are they getting run through Django? The shared hosting setup doesn't allow for a <Location> block, but there's a flag in the rewrite rule that says only requests for files that don't exist in the filesystem should be processed. All of my static files exist on the system, though they are symbolically linked files if it matters.

  Read the article

• KVM-Guests can't get past bridge - no internet connection

  - by tmn29a

  I'm running a backported KVM on a Debian Squeeze. ATM the KVM-Guest can't connect to the internet through the bridge I have set up. The guests can reach each other, the host but nothing outside. I can neither ping, nslookup or do anything to a remote address. The guest are configured to have a static IP. When I didn;t have the bridge but a virtual bridge (the KVM-default) the guest could connect fine. After setting up the bridge things broke, so I think the problem lies there. # The loopback network interface auto lo br0 iface lo inet loopback # Bonding Interface auto bond0 iface bond0 inet static address 10.XXX.XXX.84 netmask 255.255.255.192 network 10.XXX.XXX.64 gateway 10.XXX.XXX.65 slaves eth0 eth1 bond_mode active-backup bond_miimon 100 bond_downdelay 200 bond_updelay 200 iface br0 inet static bridge_ports eth0 eth1 address 172.xxx.xxx.65 broadcast 172.xxx.xxx.127 netmask 255.255.255.192 gateway 172.xxx.xxx.65 bridge_stp on bridge_maxwait 0 Thanks in advance for your help !

  Read the article

• Cannot Access Web Interface on HP 2510G

  - by Stephen

  I am currently setting up a new infrastructure with HP 2510s as edge switches and an HP E5406 as the main switch. I also have a DHCP and DNS server running on the same network. When i first set up one of my 2510 switches, I gave it a static IP through the console and then went to the web interface to continue my configuration. Later, I realized that I assigned it the wrong IP address, so i went through the web interface and changed the IP address to the correct one. Now, I can't access the web interface. I can telnet to the switch on the new IP address, but the web interface will not load. If I switch from static IP to DHCP, it loads the web interface. Any ideas on what could be causing the web server in the 2510 not to load with the new static IP address?

  Read the article

• Apache mod_jk replacing mod_rewrite rules

  - by organicveggie

  We have a slightly complex Apache 2.2 setup in front of a Tomcat 6.0 instance. The main Tomcat webapp is deployed in: /opt/tomcat/webapps/ROOT But we also have static content that we update semi-regularly. We didn't want to force a new build and deploy of the webapp, so that's stored separately in folders like: /opt/tomcat/webapps/css /opt/tomcat/webapps/foo /opt/tomcat/webapps/bar To handle this from Apache, we use mod_rewrite and rules look something like the following: RewriteCond %{REQUEST_FILENAME} -f RewriteRule ^/css/(.*)$ - [L] RewriteCond ROOT/%{REQUEST_FILENAME} -f RewriteRule ^/css/(.*)$ ROOT/$1 [L] RewriteCond %{REQUEST_FILENAME} -f RewriteRule ^(.*)\.(jpg|png|html|js)$ - [L] RewriteCond ROOT/%{REQUEST_FILENAME} -f RewriteRule ^(.*)\.(jpg|png|html|js)$ - [L] RewriteRule ^/(.*)$ http://localhost:8080/$1 [P,L] ProxyPassReverse / http://localhost:8080/ I now think I might want to start using mod_jk and I have two questions: Is it even worth using mod_jk? I don't need load balancing. Is it even possible to handle the cases I outlined where the static content is referenced as "http://www.example.com/css/foo.css", but we don't know if it's located in the Tomcat webapp or in one of the static folders.

  Read the article

• String.IsNullOrWhiteSpace

  - by Scott Dorman

  An empty string is different than an unassigned string variable (which is null), and is a string containing no characters between the quotes (""). The .NET Framework provides String.Empty to represent an empty string, and there is no practical difference between ("") and String.Empty. One of the most common string comparisons to perform is to determine if a string variable is equal to an empty string. The fastest and simplest way to determine if a string is empty is to test if the Length property is equal to 0. However, since strings are reference types it is possible for a string variable to be null, which would result in a runtime error when you tried to access the Length property. Since testing to determine if a string is empty is such a common occurrence, the .NET Framework provides the static method String.IsNullOrEmpty method: public static bool IsNullOrEmpty(string value) { if (value != null) { return (value.Length == 0); }   return true; } It is also very common to determine if a string is empty and contains more than just whitespace characters. For example, String.IsNullOrEmpty("   ") would return false, since this string is actually made up of three whitespace characters. In some cases, this may be acceptable, but in many others it is not. TO help simplify testing this scenario, the .NET Framework 4 introduces the String.IsNullOrWhiteSpace method: public static bool IsNullOrWhiteSpace(string value) { if (value != null) { for (int i = 0; i < value.Length; i++) { if (!char.IsWhiteSpace(value[i])) { return false; } } } return true; }   Using either String.IsNullOrEmpty or String.IsNullOrWhiteSpace helps ensure correctness, readability, and consistency, so they should be used in all situations where you need to determine if a string is null, empty, or contains only whitespace characters. Technorati Tags: .NET,C# 4

  Read the article

• Web Server Scripting Hack to Maintain State and Keep a Domain Cookieless

  - by jasonspalace

  Hello, I am looking for a solution on a LAMP server to keep a site cookieless such as "example.com", where static content is served from "static.example.com", and with rules in place to rewrite requests for "www.example.com" to "example.com". I am really hoping to avoid setting up a cookieless domain for the static content due to an unanswered SEO concern with regards to CNAMEing to a CDN. Is there a way, (or safe hack), that can be implemented where a second domain such as "www.example2.com" is CNAMEd, aliased, or otherwise used with "example.com" to somehow trick a php application into maintaining state with a cookie dropped on "www.example2.com" therefore keeping all of "example.com" cookieless? If such a solution is feasible, what implications would exists with regards to SSL and cross-browser compatibility other than requiring users to accept cookies from 3rd party domains and possibly needing an additional SSL to keep the cookie secure? Thanks in advance to all.

  Read the article

• PHP Aspect Oriented Design

  - by Devin Dixon

  This is a continuation of this Code Review question. What was taken away from that post, and other aspect oriented design is it is hard to debug. To counter that, I implemented the ability to turn tracing of the design patterns on. Turning trace on works like: //This can be added anywhere in the code Run::setAdapterTrace(true); Run::setFilterTrace(true); Run::setObserverTrace(true); //Execute the functon echo Run::goForARun(8); In the actual log with the trace turned on, it outputs like so: adapter 2012-02-12 21:46:19 {"type":"closure","object":"static","call_class":"\/public_html\/examples\/design\/ClosureDesigns.php","class":"Run","method":"goForARun","call_method":"goForARun","trace":"Run::goForARun","start_line":68,"end_line":70} filter 2012-02-12 22:05:15 {"type":"closure","event":"return","object":"static","class":"run_filter","method":"\/home\/prodigyview\/public_html\/examples\/design\/ClosureDesigns.php","trace":"Run::goForARun","start_line":51,"end_line":58} observer 2012-02-12 22:05:15 {"type":"closure","object":"static","class":"run_observer","method":"\/home\/prodigyview\/public_html\/public\/examples\/design\/ClosureDesigns.php","trace":"Run::goForARun","start_line":61,"end_line":63} When the information is broken down, the data translates to: Called by an adapter or filter or observer The function called was a closure The location of the closure Class:method the adapter was implemented on The Trace of where the method was called from Start Line and End Line The code has been proven to work in production environments and features various examples of to implement, so the proof of concept is there. It is not DI and accomplishes things that DI cannot. I wouldn't call the code boilerplate but I would call it bloated. In summary, the weaknesses are bloated code and a learning curve in exchange for aspect oriented functionality. Beyond the normal fear of something new and different, what are other weakness in this implementation of aspect oriented design, if any? PS: More examples of AOP here: https://github.com/ProdigyView/ProdigyView/tree/master/examples/design

  Read the article

• Movement and Collision with AABB

  - by Jeremy Giberson

  I'm having a little difficulty figuring out the following scenarios. http://i.stack.imgur.com/8lM6i.png In scenario A, the moving entity has fallen to (and slightly into the floor). The current position represents the projected position that will occur if I apply the acceleration & velocity as usual without worrying about collision. The Next position, represents the corrected projection position after collision check. The resulting end position is the falling entity now rests ON the floor--that is, in a consistent state of collision by sharing it's bottom X axis with the floor's top X axis. My current update loop looks like the following: // figure out forces & accelerations and project an objects next position // check collision occurrence from current position -> projected position // if a collision occurs, adjust projection position Which seems to be working for the scenario of my object falling to the floor. However, the situation becomes sticky when trying to figure out scenario's B & C. In scenario B, I'm attempt to move along the floor on the X axis (player is pressing right direction button) additionally, gravity is pulling the object into the floor. The problem is, when the object attempts to move the collision detection code is going to recognize that the object is already colliding with the floor to begin with, and auto correct any movement back to where it was before. In scenario C, I'm attempting to jump off the floor. Again, because the object is already in a constant collision with the floor, when the collision routine checks to make sure moving from current position to projected position doesn't result in a collision, it will fail because at the beginning of the motion, the object is already colliding. How do you allow movement along the edge of an object? How do you allow movement away from an object you are already colliding with. Extra Info My collision routine is based on AABB sweeping test from an old gamasutra article, http://www.gamasutra.com/view/feature/3383/simple_intersection_tests_for_games.php?page=3 My bounding box implementation is based on top left/bottom right instead of midpoint/extents, so my min/max functions are adjusted. Otherwise, here is my bounding box class with collision routines: public class BoundingBox { public XYZ topLeft; public XYZ bottomRight; public BoundingBox(float x, float y, float z, float w, float h, float d) { topLeft = new XYZ(); bottomRight = new XYZ(); topLeft.x = x; topLeft.y = y; topLeft.z = z; bottomRight.x = x+w; bottomRight.y = y+h; bottomRight.z = z+d; } public BoundingBox(XYZ position, XYZ dimensions, boolean centered) { topLeft = new XYZ(); bottomRight = new XYZ(); topLeft.x = position.x; topLeft.y = position.y; topLeft.z = position.z; bottomRight.x = position.x + (centered ? dimensions.x/2 : dimensions.x); bottomRight.y = position.y + (centered ? dimensions.y/2 : dimensions.y); bottomRight.z = position.z + (centered ? dimensions.z/2 : dimensions.z); } /** * Check if a point lies inside a bounding box * @param box * @param point * @return */ public static boolean isPointInside(BoundingBox box, XYZ point) { if(box.topLeft.x <= point.x && point.x <= box.bottomRight.x && box.topLeft.y <= point.y && point.y <= box.bottomRight.y && box.topLeft.z <= point.z && point.z <= box.bottomRight.z) return true; return false; } /** * Check for overlap between two bounding boxes using separating axis theorem * if two boxes are separated on any axis, they cannot be overlapping * @param a * @param b * @return */ public static boolean isOverlapping(BoundingBox a, BoundingBox b) { XYZ dxyz = new XYZ(b.topLeft.x - a.topLeft.x, b.topLeft.y - a.topLeft.y, b.topLeft.z - a.topLeft.z); // if b - a is positive, a is first on the axis and we should use its extent // if b -a is negative, b is first on the axis and we should use its extent // check for x axis separation if ((dxyz.x >= 0 && a.bottomRight.x-a.topLeft.x < dxyz.x) // negative scale, reverse extent sum, flip equality ||(dxyz.x < 0 && b.topLeft.x-b.bottomRight.x > dxyz.x)) return false; // check for y axis separation if ((dxyz.y >= 0 && a.bottomRight.y-a.topLeft.y < dxyz.y) // negative scale, reverse extent sum, flip equality ||(dxyz.y < 0 && b.topLeft.y-b.bottomRight.y > dxyz.y)) return false; // check for z axis separation if ((dxyz.z >= 0 && a.bottomRight.z-a.topLeft.z < dxyz.z) // negative scale, reverse extent sum, flip equality ||(dxyz.z < 0 && b.topLeft.z-b.bottomRight.z > dxyz.z)) return false; // not separated on any axis, overlapping return true; } public static boolean isContactEdge(int xyzAxis, BoundingBox a, BoundingBox b) { switch(xyzAxis) { case XYZ.XCOORD: if(a.topLeft.x == b.bottomRight.x || a.bottomRight.x == b.topLeft.x) return true; return false; case XYZ.YCOORD: if(a.topLeft.y == b.bottomRight.y || a.bottomRight.y == b.topLeft.y) return true; return false; case XYZ.ZCOORD: if(a.topLeft.z == b.bottomRight.z || a.bottomRight.z == b.topLeft.z) return true; return false; } return false; } /** * Sweep test min extent value * @param box * @param xyzCoord * @return */ public static float min(BoundingBox box, int xyzCoord) { switch(xyzCoord) { case XYZ.XCOORD: return box.topLeft.x; case XYZ.YCOORD: return box.topLeft.y; case XYZ.ZCOORD: return box.topLeft.z; default: return 0f; } } /** * Sweep test max extent value * @param box * @param xyzCoord * @return */ public static float max(BoundingBox box, int xyzCoord) { switch(xyzCoord) { case XYZ.XCOORD: return box.bottomRight.x; case XYZ.YCOORD: return box.bottomRight.y; case XYZ.ZCOORD: return box.bottomRight.z; default: return 0f; } } /** * Test if bounding box A will overlap bounding box B at any point * when box A moves from position 0 to position 1 and box B moves from position 0 to position 1 * Note, sweep test assumes bounding boxes A and B's dimensions do not change * * @param a0 box a starting position * @param a1 box a ending position * @param b0 box b starting position * @param b1 box b ending position * @param aCollisionOut xyz of box a's position when/if a collision occurs * @param bCollisionOut xyz of box b's position when/if a collision occurs * @return */ public static boolean sweepTest(BoundingBox a0, BoundingBox a1, BoundingBox b0, BoundingBox b1, XYZ aCollisionOut, XYZ bCollisionOut) { // solve in reference to A XYZ va = new XYZ(a1.topLeft.x-a0.topLeft.x, a1.topLeft.y-a0.topLeft.y, a1.topLeft.z-a0.topLeft.z); XYZ vb = new XYZ(b1.topLeft.x-b0.topLeft.x, b1.topLeft.y-b0.topLeft.y, b1.topLeft.z-b0.topLeft.z); XYZ v = new XYZ(vb.x-va.x, vb.y-va.y, vb.z-va.z); // check for initial overlap if(BoundingBox.isOverlapping(a0, b0)) { // java pass by ref/value gotcha, have to modify value can't reassign it aCollisionOut.x = a0.topLeft.x; aCollisionOut.y = a0.topLeft.y; aCollisionOut.z = a0.topLeft.z; bCollisionOut.x = b0.topLeft.x; bCollisionOut.y = b0.topLeft.y; bCollisionOut.z = b0.topLeft.z; return true; } // overlap min/maxs XYZ u0 = new XYZ(); XYZ u1 = new XYZ(1,1,1); float t0, t1; // iterate axis and find overlaps times (x=0, y=1, z=2) for(int i = 0; i < 3; i++) { float aMax = max(a0, i); float aMin = min(a0, i); float bMax = max(b0, i); float bMin = min(b0, i); float vi = XYZ.getCoord(v, i); if(aMax < bMax && vi < 0) XYZ.setCoord(u0, i, (aMax-bMin)/vi); else if(bMax < aMin && vi > 0) XYZ.setCoord(u0, i, (aMin-bMax)/vi); if(bMax > aMin && vi < 0) XYZ.setCoord(u1, i, (aMin-bMax)/vi); else if(aMax > bMin && vi > 0) XYZ.setCoord(u1, i, (aMax-bMin)/vi); } // get times of collision t0 = Math.max(u0.x, Math.max(u0.y, u0.z)); t1 = Math.min(u1.x, Math.min(u1.y, u1.z)); // collision only occurs if t0 < t1 if(t0 <= t1 && t0 != 0) // not t0 because we already tested it! { // t0 is the normalized time of the collision // then the position of the bounding boxes would // be their original position + velocity*time aCollisionOut.x = a0.topLeft.x + va.x*t0; aCollisionOut.y = a0.topLeft.y + va.y*t0; aCollisionOut.z = a0.topLeft.z + va.z*t0; bCollisionOut.x = b0.topLeft.x + vb.x*t0; bCollisionOut.y = b0.topLeft.y + vb.y*t0; bCollisionOut.z = b0.topLeft.z + vb.z*t0; return true; } else return false; } }

  Read the article

• BizTalk 2009 - Pipeline Component Wizard

  - by Stuart Brierley

  Recently I decided to try out the BizTalk Server Pipeline Component Wizard when creating a new pipeline component for BizTalk 2009. There are different versions of the wizard available, so be sure to download the appropriate version for the BizTalk environment that you are working with. Following the download and expansion of the zip file, you should be left with a Visual Studio solution.  Open this solution and build the project. Following this installation is straight foward - locate and run the built setup.exe file in the PipelineComponentWizard Setup project and click through the small number of installation screens. Once you have completed installation you will be ready to use the wizard in Visual Studio to create your BizTalk Pipeline Component. Start by creating a new project, selecting BizTalk Projects then BizTalk Server Pipeline Component.  You will then be presented with the splash screen. The next step is General Setup, where you will detail the classname, namespace, pipeline and component types, and the implementation language for your Pipeline Component. The options for pipeline type are Receive, Send or Any. Depending on the pipeline type chosen there are different options presented for the component type, matching those available within the BizTalk Pipelines themselves: Receive - Decoder, Disassembling Parser, Validate, Party Resolver, Any. Send -  Encoder, Assembling Serializer, Any. Any - Any. The options for implementation language are C# or VB.Net Next you must set up the UI settings - these are the settings that affect the appearance of the pipeline component within Visual Studio. You must detail the component name, version, description and icon.  Next is the definition of the variables that the pipeline component will use.  The values for these variables will be defined in Visual Studio when creating a pipeline. The options for each variable you require are: Designer Property - The name of the variable. Data Type - String, Boolean, Integer, Long, Short, Schema List, Schema With None Clicking finish now will complete the wizard stage of the creation of your pipeline component. Once the wizard has completed you will be left with a BizTalk Server Pipeline Component project containing a skeleton code file for you to complete.   Within this code file you will mainly be interested in the execute method, which is left mostly empty ready for you to implement your custom pipeline code:          #region IComponent members         /// <summary>         /// Implements IComponent.Execute method.         /// </summary>         /// <param name="pc">Pipeline context</param>         /// <param name="inmsg">Input message</param>         /// <returns>Original input message</returns>         /// <remarks>         /// IComponent.Execute method is used to initiate         /// the processing of the message in this pipeline component.         /// </remarks>         public Microsoft.BizTalk.Message.Interop.IBaseMessage Execute(Microsoft.BizTalk.Component.Interop.IPipelineContext pc, Microsoft.BizTalk.Message.Interop.IBaseMessage inmsg)         {             //             // TODO: implement component logic             //             // this way, it's a passthrough pipeline component             return inmsg;         }         #endregion Once you have implemented your custom code, build and compile your Custom Pipeline Component then add the compiled .dll to C:\Program Files\Microsoft BizTalk Server 2009\Pipeline Components . When creating a new pipeline, in Visual Studio reset the toolbox and the custom pipeline component should appear ready for you to use in your Biztalk Pipeline. Drop the pipeline component into the relevant pipeline stage and configure the component properties (the variables defined in the wizard). You can now deploy and use the pipeline as you would any other custom pipeline.

  Read the article

• Unit testing statically typed functional code

  - by back2dos

  I wanted to ask you people, in which cases it makes sense to unit test statically typed functional code, as written in haskell, scala, ocaml, nemerle, f# or haXe (the last is what I am really interested in, but I wanted to tap into the knowledge of the bigger communities). I ask this because from my understanding: One aspect of unit tests is to have the specs in runnable form. However when employing a declarative style, that directly maps the formalized specs to language semantics, is it even actually possible to express the specs in runnable form in a separate way, that adds value? The more obvious aspect of unit tests is to track down errors that cannot be revealed through static analysis. Given that type safe functional code is a good tool to code extremely close to what your static analyzer understands. However a simple mistake like using x instead of y (both being coordinates) in your code cannot be covered. However such a mistake could also arise while writing the test code, so I am not sure whether its worth the effort. Unit tests do introduce redundancy, which means that when requirements change, the code implementing them and the tests covering this code must both be changed. This overhead of course is about constant, so one could argue, that it doesn't really matter. In fact, in languages like Ruby it really doesn't compared to the benefits, but given how statically typed functional programming covers a lot of the ground unit tests are intended for, it feels like it's a constant overhead one can simply reduce without penalty. From this I'd deduce that unit tests are somewhat obsolete in this programming style. Of course such a claim can only lead to religious wars, so let me boil this down to a simple question: When you use such a programming style, to which extents do you use unit tests and why (what quality is it you hope to gain for your code)? Or the other way round: do you have criteria by which you can qualify a unit of statically typed functional code as covered by the static analyzer and hence needs no unit test coverage?

  Read the article

• Anatomy of a .NET Assembly - Signature encodings

  - by Simon Cooper

  If you've just joined this series, I highly recommend you read the previous posts in this series, starting here, or at least these posts, covering the CLR metadata tables. Before we look at custom attribute encoding, we first need to have a brief look at how signatures are encoded in an assembly in general. Signature types There are several types of signatures in an assembly, all of which share a common base representation, and are all stored as binary blobs in the #Blob heap, referenced by an offset from various metadata tables. The types of signatures are: Method definition and method reference signatures. Field signatures Property signatures Method local variables. These are referenced from the StandAloneSig table, which is then referenced by method body headers. Generic type specifications. These represent a particular instantiation of a generic type. Generic method specifications. Similarly, these represent a particular instantiation of a generic method. All these signatures share the same underlying mechanism to represent a type Representing a type All metadata signatures are based around the ELEMENT_TYPE structure. This assigns a number to each 'built-in' type in the framework; for example, Uint16 is 0x07, String is 0x0e, and Object is 0x1c. Byte codes are also used to indicate SzArrays, multi-dimensional arrays, custom types, and generic type and method variables. However, these require some further information. Firstly, custom types (ie not one of the built-in types). These require you to specify the 4-byte TypeDefOrRef coded token after the CLASS (0x12) or VALUETYPE (0x11) element type. This 4-byte value is stored in a compressed format before being written out to disk (for more excruciating details, you can refer to the CLI specification). SzArrays simply have the array item type after the SZARRAY byte (0x1d). Multidimensional arrays follow the ARRAY element type with a series of compressed integers indicating the number of dimensions, and the size and lower bound of each dimension. Generic variables are simply followed by the index of the generic variable they refer to. There are other additions as well, for example, a specific byte value indicates a method parameter passed by reference (BYREF), and other values indicating custom modifiers. Some examples... To demonstrate, here's a few examples and what the resulting blobs in the #Blob heap will look like. Each name in capitals corresponds to a particular byte value in the ELEMENT_TYPE or CALLCONV structure, and coded tokens to custom types are represented by the type name in curly brackets. A simple field: int intField; FIELD I4 A field of an array of a generic type parameter (assuming T is the first generic parameter of the containing type): T[] genArrayField FIELD SZARRAY VAR 0 An instance method signature (note how the number of parameters does not include the return type): instance string MyMethod(MyType, int&, bool[][]); HASTHIS DEFAULT 3 STRING CLASS {MyType} BYREF I4 SZARRAY SZARRAY BOOLEAN A generic type instantiation: MyGenericType<MyType, MyStruct> GENERICINST CLASS {MyGenericType} 2 CLASS {MyType} VALUETYPE {MyStruct} For more complicated examples, in the following C# type declaration: GenericType<T> : GenericBaseType<object[], T, GenericType<T>> { ... } the Extends field of the TypeDef for GenericType will point to a TypeSpec with the following blob: GENERICINST CLASS {GenericBaseType} 3 SZARRAY OBJECT VAR 0 GENERICINST CLASS {GenericType} 1 VAR 0 And a static generic method signature (generic parameters on types are referenced using VAR, generic parameters on methods using MVAR): TResult[] GenericMethod<TInput, TResult>( TInput, System.Converter<TInput, TOutput>); GENERIC 2 2 SZARRAY MVAR 1 MVAR 0 GENERICINST CLASS {System.Converter} 2 MVAR 0 MVAR 1 As you can see, complicated signatures are recursively built up out of quite simple building blocks to represent all the possible variations in a .NET assembly. Now we've looked at the basics of normal method signatures, in my next post I'll look at custom attribute application signatures, and how they are different to normal signatures.

  Read the article

• Taming Hopping Windows

  - by Roman Schindlauer

  At first glance, hopping windows seem fairly innocuous and obvious. They organize events into windows with a simple periodic definition: the windows have some duration d (e.g. a window covers 5 second time intervals), an interval or period p (e.g. a new window starts every 2 seconds) and an alignment a (e.g. one of those windows starts at 12:00 PM on March 15, 2012 UTC). var wins = xs     .HoppingWindow(TimeSpan.FromSeconds(5),                    TimeSpan.FromSeconds(2),                    new DateTime(2012, 3, 15, 12, 0, 0, DateTimeKind.Utc)); Logically, there is a window with start time a + np and end time a + np + d for every integer n. That’s a lot of windows. So why doesn’t the following query (always) blow up? var query = wins.Select(win => win.Count()); A few users have asked why StreamInsight doesn’t produce output for empty windows. Primarily it’s because there is an infinite number of empty windows! (Actually, StreamInsight uses DateTimeOffset.MaxValue to approximate “the end of time” and DateTimeOffset.MinValue to approximate “the beginning of time”, so the number of windows is lower in practice.) That was the good news. Now the bad news. Events also have duration. Consider the following simple input: var xs = this.Application                 .DefineEnumerable(() => new[]                     { EdgeEvent.CreateStart(DateTimeOffset.UtcNow, 0) })                 .ToStreamable(AdvanceTimeSettings.IncreasingStartTime); Because the event has no explicit end edge, it lasts until the end of time. So there are lots of non-empty windows if we apply a hopping window to that single event! For this reason, we need to be careful with hopping window queries in StreamInsight. Or we can switch to a custom implementation of hopping windows that doesn’t suffer from this shortcoming. The alternate window implementation produces output only when the input changes. We start by breaking up the timeline into non-overlapping intervals assigned to each window. In figure 1, six hopping windows (“Windows”) are assigned to six intervals (“Assignments”) in the timeline. Next we take input events (“Events”) and alter their lifetimes (“Altered Events”) so that they cover the intervals of the windows they intersect. In figure 1, you can see that the first event e1 intersects windows w1 and w2 so it is adjusted to cover assignments a1 and a2. Finally, we can use snapshot windows (“Snapshots”) to produce output for the hopping windows. Notice however that instead of having six windows generating output, we have only four. The first and second snapshots correspond to the first and second hopping windows. The remaining snapshots however cover two hopping windows each! While in this example we saved only two events, the savings can be more significant when the ratio of event duration to window duration is higher. Figure 1: Timeline The implementation of this strategy is straightforward. We need to set the start times of events to the start time of the interval assigned to the earliest window including the start time. Similarly, we need to modify the end times of events to the end time of the interval assigned to the latest window including the end time. The following snap-to-boundary function that rounds a timestamp value t down to the nearest value t' <= t such that t' is a + np for some integer n will be useful. For convenience, we will represent both DateTime and TimeSpan values using long ticks: static long SnapToBoundary(long t, long a, long p) {     return t - ((t - a) % p) - (t > a ? 0L : p); } How do we find the earliest window including the start time for an event? It’s the window following the last window that does not include the start time assuming that there are no gaps in the windows (i.e. duration < interval), and limitation of this solution. To find the end time of that antecedent window, we need to know the alignment of window ends: long e = a + (d % p); Using the window end alignment, we are finally ready to describe the start time selector: static long AdjustStartTime(long t, long e, long p) {     return SnapToBoundary(t, e, p) + p; } To find the latest window including the end time for an event, we look for the last window start time (non-inclusive): public static long AdjustEndTime(long t, long a, long d, long p) {     return SnapToBoundary(t - 1, a, p) + p + d; } Bringing it together, we can define the translation from events to ‘altered events’ as in Figure 1: public static IQStreamable<T> SnapToWindowIntervals<T>(IQStreamable<T> source, TimeSpan duration, TimeSpan interval, DateTime alignment) {     if (source == null) throw new ArgumentNullException("source");     // reason about DateTime and TimeSpan in ticks     long d = Math.Min(DateTime.MaxValue.Ticks, duration.Ticks);     long p = Math.Min(DateTime.MaxValue.Ticks, Math.Abs(interval.Ticks));     // set alignment to earliest possible window     var a = alignment.ToUniversalTime().Ticks % p;     // verify constraints of this solution     if (d <= 0L) { throw new ArgumentOutOfRangeException("duration"); }     if (p == 0L || p > d) { throw new ArgumentOutOfRangeException("interval"); }     // find the alignment of window ends     long e = a + (d % p);     return source.AlterEventLifetime(         evt => ToDateTime(AdjustStartTime(evt.StartTime.ToUniversalTime().Ticks, e, p)),         evt => ToDateTime(AdjustEndTime(evt.EndTime.ToUniversalTime().Ticks, a, d, p)) -             ToDateTime(AdjustStartTime(evt.StartTime.ToUniversalTime().Ticks, e, p))); } public static DateTime ToDateTime(long ticks) {     // just snap to min or max value rather than under/overflowing     return ticks < DateTime.MinValue.Ticks         ? new DateTime(DateTime.MinValue.Ticks, DateTimeKind.Utc)         : ticks > DateTime.MaxValue.Ticks         ? new DateTime(DateTime.MaxValue.Ticks, DateTimeKind.Utc)         : new DateTime(ticks, DateTimeKind.Utc); } Finally, we can describe our custom hopping window operator: public static IQWindowedStreamable<T> HoppingWindow2<T>(     IQStreamable<T> source,     TimeSpan duration,     TimeSpan interval,     DateTime alignment) {     if (source == null) { throw new ArgumentNullException("source"); }     return SnapToWindowIntervals(source, duration, interval, alignment).SnapshotWindow(); } By switching from HoppingWindow to HoppingWindow2 in the following example, the query returns quickly rather than gobbling resources and ultimately failing! public void Main() {     var start = new DateTimeOffset(new DateTime(2012, 6, 28), TimeSpan.Zero);     var duration = TimeSpan.FromSeconds(5);     var interval = TimeSpan.FromSeconds(2);     var alignment = new DateTime(2012, 3, 15, 12, 0, 0, DateTimeKind.Utc);     var events = this.Application.DefineEnumerable(() => new[]     {         EdgeEvent.CreateStart(start.AddSeconds(0), "e0"),         EdgeEvent.CreateStart(start.AddSeconds(1), "e1"),         EdgeEvent.CreateEnd(start.AddSeconds(1), start.AddSeconds(2), "e1"),         EdgeEvent.CreateStart(start.AddSeconds(3), "e2"),         EdgeEvent.CreateStart(start.AddSeconds(9), "e3"),         EdgeEvent.CreateEnd(start.AddSeconds(3), start.AddSeconds(10), "e2"),         EdgeEvent.CreateEnd(start.AddSeconds(9), start.AddSeconds(10), "e3"),     }).ToStreamable(AdvanceTimeSettings.IncreasingStartTime);     var adjustedEvents = SnapToWindowIntervals(events, duration, interval, alignment);     var query = from win in HoppingWindow2(events, duration, interval, alignment)                 select win.Count();     DisplayResults(adjustedEvents, "Adjusted Events");     DisplayResults(query, "Query"); } As you can see, instead of producing a massive number of windows for the open start edge e0, a single window is emitted from 12:00:15 AM until the end of time: Adjusted Events StartTime EndTime Payload 6/28/2012 12:00:01 AM 12/31/9999 11:59:59 PM e0 6/28/2012 12:00:03 AM 6/28/2012 12:00:07 AM e1 6/28/2012 12:00:05 AM 6/28/2012 12:00:15 AM e2 6/28/2012 12:00:11 AM 6/28/2012 12:00:15 AM e3 Query StartTime EndTime Payload 6/28/2012 12:00:01 AM 6/28/2012 12:00:03 AM 1 6/28/2012 12:00:03 AM 6/28/2012 12:00:05 AM 2 6/28/2012 12:00:05 AM 6/28/2012 12:00:07 AM 3 6/28/2012 12:00:07 AM 6/28/2012 12:00:11 AM 2 6/28/2012 12:00:11 AM 6/28/2012 12:00:15 AM 3 6/28/2012 12:00:15 AM 12/31/9999 11:59:59 PM 1 Regards, The StreamInsight Team

  Read the article

• What is the evidence that an API has exceeded its orthogonality in the context of types?

  - by hawkeye

  Wikipedia defines software orthogonality as: orthogonality in a programming language means that a relatively small set of primitive constructs can be combined in a relatively small number of ways to build the control and data structures of the language. The term is most-frequently used regarding assembly instruction sets, as orthogonal instruction set. Jason Coffin has defined software orthogonality as Highly cohesive components that are loosely coupled to each other produce an orthogonal system. C.Ross has defined software orthogonality as: the property that means "Changing A does not change B". An example of an orthogonal system would be a radio, where changing the station does not change the volume and vice-versa. Now there is a hypothesis published in the the ACM Queue by Tim Bray - that some have called the Bánffy Bray Type System Criteria - which he summarises as: Static typings attractiveness is a direct function (and dynamic typings an inverse function) of API surface size. Dynamic typings attractiveness is a direct function (and static typings an inverse function) of unit testing workability. Now Stuart Halloway has reformulated Banfy Bray as: the more your APIs exceed orthogonality, the better you will like static typing My question is: What is the evidence that an API has exceeded its orthogonality in the context of types? Clarification Tim Bray introduces the idea of orthogonality and APIs. Where you have one API and it is mainly dealing with Strings (ie a web server serving requests and responses), then a uni-typed language (python, ruby) is 'aligned' to that API - because the the type system of these languages isn't sophisticated, but it doesn't matter since you're dealing with Strings anyway. He then moves on to Android programming, which has a whole bunch of sensor APIs, which are all 'different' to the web server API that he was working on previously. Because you're not just dealing with Strings, but with different types, the API is non-orthogonal. Tim's point is that there is a empirical relationship between your 'liking' of types and the API you're programming against. (ie a subjective point is actually objective depending on your context).

  Read the article

< Previous Page | 191 192 193 194 195 196 197 198 199 200 201 202  | Next Page >