Search Results

Search found 45316 results on 1813 pages for 'class literals'.

Page 853/1813 | < Previous Page | 849 850 851 852 853 854 855 856 857 858 859 860  | Next Page >

  • Trying to run my code and compiler seems to just close after it executes [migrated]

    - by Shane
    I am trying to run a program and the compiler seems to just crash right after it executes ... i have no build errors so i am wondering what the hell is going on ... I am a bit of a novice so all help would be appreciated =). I don't know if you might have time to scan through the code but this is what i have got : using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading.Tasks; namespace ConsoleApplication1 { public class Student { string Fname, Lname, Program ; int Sid ; // Inputting information for students public void InputStudentInfo () { Console.WriteLine ("Please enter your first name") ; Fname = Console.ReadLine() ; Console.WriteLine ("Please enter you last name") ; Lname = Console.ReadLine() ; Console.WriteLine ("Please enter you student ID#") ; Sid = int.Parse(Console.ReadLine()) ; Console.WriteLine ("Enter the Program that you are completeing") ; Program = Console.ReadLine() ; } // Printing information for students public void PrintStudentInfo () { Console.Write (" Your name is " + Fname) ; Console.Write(" " + Lname); Console.WriteLine (" Your student identification number is " + Sid) ; Console.WriteLine (" The program you are registered for is " + Program) ; } /* public void MenuInterface() { Console.WriteLine (" 1. Input Student information" ) ; Console.WriteLine (" 2. Input Course information" ) ; Console.WriteLine (" 3. Input Grade information" ) ; Console.WriteLine (" 4. Print Course information" ) ; Console.WriteLine (" 5. Print Student information" ) ; Console.WriteLine (" 6. Print Grade information" ) ; Console.WriteLine (" 7. Print Student information including Course they are registered in and the grade obtained for that course" ) ; Console.WriteLine (" 8. Print grade info of the course in which student has achieved the highest grade" ) ; Console.WriteLine (" 0. Exit") ; Console.WriteLine (" Please select a choice from 0-8") ; accode = Console.ReadLine(); } */ } public class Course { string course1, course2, course3 ; int Stuid ; // Inputting Course Information public void InputCourseInfo () { Console.WriteLine (" Please re-enter your identification number") ; Stuid = int.Parse(Console.ReadLine()) ; Console.WriteLine (" Enter the name of your first course") ; course1 = Console.ReadLine() ; Console.WriteLine (" Enter the name of your second course") ; course2 = Console.ReadLine() ; Console.WriteLine (" Enter the name of your third course") ; course3 = Console.ReadLine() ; } // Printing Course Information public void PrintCourseInfo () { Console.WriteLine (" Your ID # is " + Stuid) ; Console.Write (" The Courses you selected are " + course1) ; Console.Write("," + course2); Console.Write(" and " + course3); } } public class Grade : Course { int Studentid ; int [] hwgrade ; int [] cwgrade ; int [] midegrade ; int [] finalegrade ; int [] totalgrade ; string coursename ; public Grade ( string cname , int Studentident , int [] homework , int [] classwork , int [] midexam , int [] finalexam) { coursename = cname ; Studentid = Studentident ; hwgrade = homework ; cwgrade = classwork ; midegrade = midexam ; finalegrade = finalexam ; } public string coname { get { return coursename ; } set { coursename = value ; } } public int Studentidenty { get { return Studentid ; } set { Studentid = value ; } } public void InputGradeInfo() { Console.WriteLine (" Please enter your Student ID" ) ; grade.Studentidenty = Console.ReadLine() ; for ( int i = 0; i < 3; i++) { Console.Writeline (" Please enter the Course name" ) ; grade.coname[i] = Console.Readline() ; Console.Writeline (" Please enter your homework grade") ; grade.hwgrade[i] = int.parse(Console.Readline()) ; // ..... } } public void CalcTotalGrade() { for (int i = 0; i < 3; i++) { grade.courseper[i] = (grade.hwgrade[i] + grade.cwgrade[i]) / 2; grade.finalper[i] = (grade.midexam[i] + grade.finalegrade[i]) / 2; grade.totalgrade[i] = (grade.courseper[i] + finalper[i]) / 2; } } public void PrintGradeInfo() { for ( int i = 0; i < 3; i++) { Console.Writeline (" Your homework grade is" + grade.hwgrade[i]) ; // ..... } } static void Main(string[] args) { int accode ; Student student = new Student() ; Course course = new Course() ; Grade grade = new Grade() ; do { Console.WriteLine(" 1. Input Student information"); Console.WriteLine(" 2. Input Course information"); Console.WriteLine(" 3. Input Grade information"); Console.WriteLine(" 4. Print Course information"); Console.WriteLine(" 5. Print Student information"); Console.WriteLine(" 6. Print Grade information"); Console.WriteLine(" 7. Print Student information including Course they are registered in and the grade obtained for that course"); Console.WriteLine(" 8. Print grade info of the course in which student has achieved the highest grade"); Console.WriteLine(" 0. Exit"); Console.WriteLine(" Please select a choice from 0-8"); accode = Console.ReadLine(); switch (accode) { case 1: student.InputStudentInfo(); break; case 2: course.InputCourseInfo(); break; case 3: grade.InputGradeInfo(); break; case 4: course.PrintCourseInfo(); break; case 5: student.PRintStudentInfo(); break; case 6: grade.PrintGradeInfo(); break; case 0: Console.WriteLine(" You have chosen to exit the program have a good day. =)"); break; } } while (accode != 0); Console.ReadKey(); } } }

    Read the article

  • Oracle Solutions for Higher Education

    Curtiss Barnes, VP of Product Strategy for Education and Research describes Oracle's best in class offerings for Higher Education institutions, Oracle's tremendous global market presence and the strong partnership Oracle maintains with its education customers to ensure our products meet the needs of the industry today and into the future.

    Read the article

  • Global Cache CR Requested But Current Block Received

    - by Liu Maclean(???)
    ????????«MINSCN?Cache Fusion Read Consistent» ????,???????????? ??????????????????: SQL> select * from V$version; BANNER -------------------------------------------------------------------------------- Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production PL/SQL Release 11.2.0.3.0 - Production CORE 11.2.0.3.0 Production TNS for Linux: Version 11.2.0.3.0 - Production NLSRTL Version 11.2.0.3.0 - Production SQL> select count(*) from gv$instance; COUNT(*) ---------- 2 SQL> select * from global_name; GLOBAL_NAME -------------------------------------------------------------------------------- www.oracledatabase12g.com ?11gR2 2??RAC??????????status???XG,????Xcurrent block???INSTANCE 2?hold?,?????INSTANCE 1?????????,?????: SQL> select * from test; ID ---------- 1 2 SQL> select dbms_rowid.rowid_block_number(rowid),dbms_rowid.rowid_relative_fno(rowid) from test; DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID) DBMS_ROWID.ROWID_RELATIVE_FNO(ROWID) ------------------------------------ ------------------------------------ 89233 1 89233 1 SQL> alter system flush buffer_cache; System altered. INSTANCE 1 Session A: SQL> update test set id=id+1 where id=1; 1 row updated. INSTANCE 1 Session B: SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 1 0 3 1755287 SQL> oradebug setmypid; Statement processed. SQL> oradebug dump gc_elements 255; Statement processed. SQL> oradebug tracefile_name; /s01/orabase/diag/rdbms/vprod/VPROD1/trace/VPROD1_ora_19111.trc GLOBAL CACHE ELEMENT DUMP (address: 0xa4ff3080): id1: 0x15c91 id2: 0x1 pkey: OBJ#76896 block: (1/89233) lock: X rls: 0x0 acq: 0x0 latch: 3 flags: 0x20 fair: 0 recovery: 0 fpin: 'kdswh11: kdst_fetch' bscn: 0x0.146e20 bctx: (nil) write: 0 scan: 0x0 lcp: (nil) lnk: [NULL] lch: [0xa9f6a6f8,0xa9f6a6f8] seq: 32 hist: 58 145:0 118 66 144:0 192 352 197 48 121 113 424 180 58 LIST OF BUFFERS LINKED TO THIS GLOBAL CACHE ELEMENT: flg: 0x02000001 lflg: 0x1 state: XCURRENT tsn: 0 tsh: 2 addr: 0xa9f6a5c8 obj: 76896 cls: DATA bscn: 0x0.1ac898 BH (0xa9f6a5c8) file#: 1 rdba: 0x00415c91 (1/89233) class: 1 ba: 0xa9e56000 set: 5 pool: 3 bsz: 8192 bsi: 0 sflg: 3 pwc: 0,15 dbwrid: 0 obj: 76896 objn: 76896 tsn: 0 afn: 1 hint: f hash: [0x91f4e970,0xbae9d5b8] lru: [0x91f58848,0xa9f6a828] lru-flags: debug_dump obj-flags: object_ckpt_list ckptq: [0x9df6d1d8,0xa9f6a740] fileq: [0xa2ece670,0xbdf4ed68] objq: [0xb4964e00,0xb4964e00] objaq: [0xb4964de0,0xb4964de0] st: XCURRENT md: NULL fpin: 'kdswh11: kdst_fetch' tch: 2 le: 0xa4ff3080 flags: buffer_dirty redo_since_read LRBA: [0x19.5671.0] LSCN: [0x0.1ac898] HSCN: [0x0.1ac898] HSUB: [1] buffer tsn: 0 rdba: 0x00415c91 (1/89233) scn: 0x0000.001ac898 seq: 0x01 flg: 0x00 tail: 0xc8980601 frmt: 0x02 chkval: 0x0000 type: 0x06=trans data ??????block: (1/89233)?GLOBAL CACHE ELEMENT DUMP?LOCK????X ??XG , ??????Current Block????Instance??modify???,????????????? ????Instance 2 ????: Instance 2 Session C: SQL> update test set id=id+1 where id=2; 1 row updated. Instance 2 Session D: SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 1 0 3 1756658 SQL> oradebug setmypid; Statement processed. SQL> oradebug dump gc_elements 255; Statement processed. SQL> oradebug tracefile_name; /s01/orabase/diag/rdbms/vprod/VPROD2/trace/VPROD2_ora_13038.trc GLOBAL CACHE ELEMENT DUMP (address: 0x89fb25a0): id1: 0x15c91 id2: 0x1 pkey: OBJ#76896 block: (1/89233) lock: XG rls: 0x0 acq: 0x0 latch: 3 flags: 0x20 fair: 0 recovery: 0 fpin: 'kduwh01: kdusru' bscn: 0x0.1acdf3 bctx: (nil) write: 0 scan: 0x0 lcp: (nil) lnk: [NULL] lch: [0x96f4cf80,0x96f4cf80] seq: 61 hist: 324 21 143:0 19 16 352 329 144:6 14 7 352 197 LIST OF BUFFERS LINKED TO THIS GLOBAL CACHE ELEMENT: flg: 0x0a000001 state: XCURRENT tsn: 0 tsh: 1 addr: 0x96f4ce50 obj: 76896 cls: DATA bscn: 0x0.1acdf6 BH (0x96f4ce50) file#: 1 rdba: 0x00415c91 (1/89233) class: 1 ba: 0x96bd4000 set: 5 pool: 3 bsz: 8192 bsi: 0 sflg: 2 pwc: 0,15 dbwrid: 0 obj: 76896 objn: 76896 tsn: 0 afn: 1 hint: f hash: [0x96ee1fe8,0xbae9d5b8] lru: [0x96f4d0b0,0x96f4cdc0] obj-flags: object_ckpt_list ckptq: [0xbdf519b8,0x96f4d5a8] fileq: [0xbdf519d8,0xbdf519d8] objq: [0xb4a47b90,0xb4a47b90] objaq: [0x96f4d0e8,0xb4a47b70] st: XCURRENT md: NULL fpin: 'kduwh01: kdusru' tch: 1 le: 0x89fb25a0 flags: buffer_dirty redo_since_read remote_transfered LRBA: [0x11.9e18.0] LSCN: [0x0.1acdf6] HSCN: [0x0.1acdf6] HSUB: [1] buffer tsn: 0 rdba: 0x00415c91 (1/89233) scn: 0x0000.001acdf6 seq: 0x01 flg: 0x00 tail: 0xcdf60601 frmt: 0x02 chkval: 0x0000 type: 0x06=trans data GCS CLIENT 0x89fb2618,6 resp[(nil),0x15c91.1] pkey 76896.0 grant 2 cvt 0 mdrole 0x42 st 0x100 lst 0x20 GRANTQ rl G0 master 1 owner 2 sid 0 remote[(nil),0] hist 0x94121c601163423c history 0x3c.0x4.0xd.0xb.0x1.0xc.0x7.0x9.0x14.0x1. cflag 0x0 sender 1 flags 0x0 replay# 0 abast (nil).x0.1 dbmap (nil) disk: 0x0000.00000000 write request: 0x0000.00000000 pi scn: 0x0000.00000000 sq[(nil),(nil)] msgseq 0x1 updseq 0x0 reqids[6,0,0] infop (nil) lockseq x2b8 pkey 76896.0 hv 93 [stat 0x0, 1->1, wm 32768, RMno 0, reminc 18, dom 0] kjga st 0x4, step 0.0.0, cinc 20, rmno 6, flags 0x0 lb 0, hb 0, myb 15250, drmb 15250, apifrz 0 ?Instance 2??????block: (1/89233)? GLOBAL CACHE ELEMENT Lock Convert?lock: XG ????GC_ELEMENTS DUMP???XCUR Cache Fusion?,???????X$ VIEW,??? X$LE X$KJBR X$KJBL, ???X$ VIEW???????????????????: INSTANCE 2 Session D: SELECT * FROM x$le WHERE le_addr IN (SELECT le_addr FROM x$bh WHERE obj IN (SELECT data_object_id FROM dba_objects WHERE owner = 'SYS' AND object_name = 'TEST') AND class = 1 AND state != 3); ADDR INDX INST_ID LE_ADDR LE_ID1 LE_ID2 ---------------- ---------- ---------- ---------------- ---------- ---------- LE_RLS LE_ACQ LE_FLAGS LE_MODE LE_WRITE LE_LOCAL LE_RECOVERY ---------- ---------- ---------- ---------- ---------- ---------- ----------- LE_BLKS LE_TIME LE_KJBL ---------- ---------- ---------------- 00007F94CA14CF60 7003 2 0000000089FB25A0 89233 1 0 0 32 2 0 1 0 1 0 0000000089FB2618 PCM Resource NAME?[ID1][ID2],[BL]???, ID1?ID2 ??blockno? fileno????, ??????????GC_elements dump?? id1: 0x15c91 id2: 0×1 pkey: OBJ#76896 block: (1/89233)?? ,?  kjblname ? kjbrname ??”[0x15c91][0x1],[BL]” ??: INSTANCE 2 Session D: SQL> set linesize 80 pagesize 1400 SQL> SELECT * 2 FROM x$kjbl l 3 WHERE l.kjblname LIKE '%[0x15c91][0x1],[BL]%'; ADDR INDX INST_ID KJBLLOCKP KJBLGRANT KJBLREQUE ---------------- ---------- ---------- ---------------- --------- --------- KJBLROLE KJBLRESP KJBLNAME ---------- ---------------- ------------------------------ KJBLNAME2 KJBLQUEUE ------------------------------ ---------- KJBLLOCKST KJBLWRITING ---------------------------------------------------------------- ----------- KJBLREQWRITE KJBLOWNER KJBLMASTER KJBLBLOCKED KJBLBLOCKER KJBLSID KJBLRDOMID ------------ ---------- ---------- ----------- ----------- ---------- ---------- KJBLPKEY ---------- 00007F94CA22A288 451 2 0000000089FB2618 KJUSEREX KJUSERNL 0 00 [0x15c91][0x1],[BL][ext 0x0,0x 89233,1,BL 0 GRANTED 0 0 1 0 0 0 0 0 76896 SQL> SELECT r.* FROM x$kjbr r WHERE r.kjbrname LIKE '%[0x15c91][0x1],[BL]%'; no rows selected Instance 1 session B: SQL> SELECT r.* FROM x$kjbr r WHERE r.kjbrname LIKE '%[0x15c91][0x1],[BL]%'; ADDR INDX INST_ID KJBRRESP KJBRGRANT KJBRNCVL ---------------- ---------- ---------- ---------------- --------- --------- KJBRROLE KJBRNAME KJBRMASTER KJBRGRANTQ ---------- ------------------------------ ---------- ---------------- KJBRCVTQ KJBRWRITER KJBRSID KJBRRDOMID KJBRPKEY ---------------- ---------------- ---------- ---------- ---------- 00007F801ACA68F8 1355 1 00000000B5A62AE0 KJUSEREX KJUSERNL 0 [0x15c91][0x1],[BL][ext 0x0,0x 0 00000000B48BB330 00 00 0 0 76896 ??????Instance 1???block: (1/89233),??????Instance 2 build cr block ????Instance 1, ?????????? ????? Instance 1? Foreground Process ? Instance 2?LMS??????RAC  TRACE: Instance 2: [oracle@vrh2 ~]$ ps -ef|grep ora_lms|grep -v grep oracle 23364 1 0 Apr29 ? 00:33:15 ora_lms0_VPROD2 SQL> oradebug setospid 23364 Oracle pid: 13, Unix process pid: 23364, image: [email protected] (LMS0) SQL> oradebug event 10046 trace name context forever,level 8:10708 trace name context forever,level 103: trace[rac.*] disk high; Statement processed. SQL> oradebug tracefile_name /s01/orabase/diag/rdbms/vprod/VPROD2/trace/VPROD2_lms0_23364.trc Instance 1 session B : SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 3 1756658 3 1756661 3 1755287 Instance 1 session A : SQL> alter session set events '10046 trace name context forever,level 8:10708 trace name context forever,level 103: trace[rac.*] disk high'; Session altered. SQL> select * from test; ID ---------- 2 2 SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 3 1761520 ?x$BH?????,???????Instance 1???build??CR block,????? TRACE ??: Instance 1 foreground Process: PARSING IN CURSOR #140336527348792 len=18 dep=0 uid=0 oct=3 lid=0 tim=1335939136125254 hv=1689401402 ad='b1a4c828' sqlid='c99yw1xkb4f1u' select * from test END OF STMT PARSE #140336527348792:c=2999,e=2860,p=0,cr=0,cu=0,mis=1,r=0,dep=0,og=1,plh=1357081020,tim=1335939136125253 EXEC #140336527348792:c=0,e=40,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939136125373 WAIT #140336527348792: nam='SQL*Net message to client' ela= 6 driver id=1650815232 #bytes=1 p3=0 obj#=0 tim=1335939136125420 *** 2012-05-02 02:12:16.125 kclscrs: req=0 block=1/89233 2012-05-02 02:12:16.125574 : kjbcro[0x15c91.1 76896.0][4] *** 2012-05-02 02:12:16.125 kclscrs: req=0 typ=nowait-abort *** 2012-05-02 02:12:16.125 kclscrs: bid=1:3:1:0:f:1e:0:0:10:0:0:0:1:2:4:1:20:0:0:0:c3:49:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:4:3:2:1:2:0:1c:0:4d:26:a3:52:0:0:0:0:c7:c:ca:62:c3:49:0:0:0:0:1:0:14:8e:47:76:1:2:dc:5:a9:fe:17:75:0:0:0:0:0:0:0:0:0:0:0:0:99:ed:0:0:0:0:0:0:10:0:0:0 2012-05-02 02:12:16.125718 : kjbcro[0x15c91.1 76896.0][4] 2012-05-02 02:12:16.125751 : GSIPC:GMBQ: buff 0xba0ee018, queue 0xbb79a7b8, pool 0x60013fa0, freeq 0, nxt 0xbb79a7b8, prv 0xbb79a7b8 2012-05-02 02:12:16.125780 : kjbsentscn[0x0.1ae0f0][to 2] 2012-05-02 02:12:16.125806 : GSIPC:SENDM: send msg 0xba0ee088 dest x20001 seq 177740 type 36 tkts xff0000 mlen x1680198 2012-05-02 02:12:16.125918 : kjbmscr(0x15c91.1)reqid=0x8(req 0xa4ff30f8)(rinst 1)hldr 2(infosz 200)(lseq x2b8) 2012-05-02 02:12:16.126959 : GSIPC:KSXPCB: msg 0xba0ee088 status 30, type 36, dest 2, rcvr 1 *** 2012-05-02 02:12:16.127 kclwcrs: wait=0 tm=1233 *** 2012-05-02 02:12:16.127 kclwcrs: got 1 blocks from ksxprcv WAIT #140336527348792: nam='gc cr block 2-way' ela= 1233 p1=1 p2=89233 p3=1 obj#=76896 tim=1335939136127199 2012-05-02 02:12:16.127272 : kjbcrcomplete[0x15c91.1 76896.0][0] 2012-05-02 02:12:16.127309 : kjbrcvdscn[0x0.1ae0f0][from 2][idx 2012-05-02 02:12:16.127329 : kjbrcvdscn[no bscn <= rscn 0x0.1ae0f0][from 2] ???? kjbcro[0x15c91.1 76896.0][4] kjbsentscn[0x0.1ae0f0][to 2] ?Instance 2??SCN=1ae0f0=1761520? block: (1/89233),???’gc cr block 2-way’ ??,?????????CR block? Instance 2 LMS TRACE 2012-05-02 02:12:15.634057 : GSIPC:RCVD: ksxp msg 0x7f16e1598588 sndr 1 seq 0.177740 type 36 tkts 0 2012-05-02 02:12:15.634094 : GSIPC:RCVD: watq msg 0x7f16e1598588 sndr 1, seq 177740, type 36, tkts 0 2012-05-02 02:12:15.634108 : GSIPC:TKT: collect msg 0x7f16e1598588 from 1 for rcvr -1, tickets 0 2012-05-02 02:12:15.634162 : kjbrcvdscn[0x0.1ae0f0][from 1][idx 2012-05-02 02:12:15.634186 : kjbrcvdscn[no bscn1, wm 32768, RMno 0, reminc 18, dom 0] kjga st 0x4, step 0.0.0, cinc 20, rmno 6, flags 0x0 lb 0, hb 0, myb 15250, drmb 15250, apifrz 0 GCS CLIENT END 2012-05-02 02:12:15.635211 : kjbdowncvt[0x15c91.1 76896.0][1][options x0] 2012-05-02 02:12:15.635230 : GSIPC:AMBUF: rcv buff 0x7f16e1c56420, pool rcvbuf, rqlen 1103 2012-05-02 02:12:15.635308 : GSIPC:GPBMSG: new bmsg 0x7f16e1c56490 mb 0x7f16e1c56420 msg 0x7f16e1c564b0 mlen 152 dest x101 flushsz -1 2012-05-02 02:12:15.635334 : kjbmslset(0x15c91.1)) seq 0x4 reqid=0x6 (shadow 0xb48bb330.xb)(rsn 2)(mas@1) 2012-05-02 02:12:15.635355 : GSIPC:SPBMSG: send bmsg 0x7f16e1c56490 blen 184 msg 0x7f16e1c564b0 mtype 33 attr|dest x30101 bsz|fsz x1ffff 2012-05-02 02:12:15.635377 : GSIPC:SNDQ: enq msg 0x7f16e1c56490, type 65521 seq 118669, inst 1, receiver 1, queued 1 *** 2012-05-02 02:12:15.635 kclccctx: cleanup copy 0x7f16e1d94798 2012-05-02 02:12:15.635479 : [kjmpmsgi:compl][type 36][msg 0x7f16e1598588][seq 177740.0][qtime 0][ptime 1257] 2012-05-02 02:12:15.635511 : GSIPC:BSEND: flushing sndq 0xb491dd28, id 1, dcx 0xbc516778, inst 1, rcvr 1 qlen 0 1 2012-05-02 02:12:15.635536 : GSIPC:BSEND: no batch1 msg 0x7f16e1c56490 type 65521 len 184 dest (1:1) 2012-05-02 02:12:15.635557 : kjbsentscn[0x0.1ae0f1][to 1] 2012-05-02 02:12:15.635578 : GSIPC:SENDM: send msg 0x7f16e1c56490 dest x10001 seq 118669 type 65521 tkts x10002 mlen xb800e8 WAIT #0: nam='gcs remote message' ela= 180 waittime=1 poll=0 event=0 obj#=0 tim=1335939135635819 2012-05-02 02:12:15.635853 : GSIPC:RCVD: ksxp msg 0x7f16e167e0b0 sndr 1 seq 0.177741 type 32 tkts 0 2012-05-02 02:12:15.635875 : GSIPC:RCVD: watq msg 0x7f16e167e0b0 sndr 1, seq 177741, type 32, tkts 0 2012-05-02 02:12:15.636012 : GSIPC:TKT: collect msg 0x7f16e167e0b0 from 1 for rcvr -1, tickets 0 2012-05-02 02:12:15.636040 : kjbrcvdscn[0x0.1ae0f1][from 1][idx 2012-05-02 02:12:15.636060 : kjbrcvdscn[no bscn <= rscn 0x0.1ae0f1][from 1] 2012-05-02 02:12:15.636082 : GSIPC:TKT: dest (1:1) rtkt not acked 1  unassigned bufs 0  tkts 0  newbufs 0 2012-05-02 02:12:15.636102 : GSIPC:TKT: remove ctx dest (1:1) 2012-05-02 02:12:15.636125 : [kjmxmpm][type 32][seq 0.177741][msg 0x7f16e167e0b0][from 1] 2012-05-02 02:12:15.636146 : kjbmpocr(0xb0.6)seq 0x1,reqid=0x23a,(client 0x9fff7b58,0x1)(from 1)(lseq xdf0) 2????LMS????????? ??gcs remote message GSIPC ????SCN=[0x0.1ae0f0] block=1/89233???,??BAST kjbmpbast(0x15c91.1),?? block=1/89233??????? ??fairness??(?11.2.0.3???_fairness_threshold=2),?current block?KCL: F156: fairness downconvert,?Xcurrent DownConvert? Scurrent: Instance 2: SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 2 0 3 1756658 ??Instance 2 LMS ?cr block??? kjbmslset(0x15c91.1)) ????SEND QUEUE GSIPC:SNDQ: enq msg 0x7f16e1c56490? ???????Instance 1???? block: (1/89233)??? ??????: Instance 2: SQL> select CURRENT_RESULTS,LIGHT_WORKS from v$cr_block_server; CURRENT_RESULTS LIGHT_WORKS --------------- ----------- 29273 437 Instance 1 session A: SQL> SQL> select * from test; ID ---------- 2 2 SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 3 1761942 3 1761932 1 0 3 1761520 Instance 2: SQL> select CURRENT_RESULTS,LIGHT_WORKS from v$cr_block_server; CURRENT_RESULTS LIGHT_WORKS --------------- ----------- 29274 437 select * from test END OF STMT PARSE #140336529675592:c=0,e=337,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939668940051 EXEC #140336529675592:c=0,e=96,p=0,cr=0,cu=0,mis=0,r=0,dep=0,og=1,plh=1357081020,tim=1335939668940204 WAIT #140336529675592: nam='SQL*Net message to client' ela= 5 driver id=1650815232 #bytes=1 p3=0 obj#=0 tim=1335939668940348 *** 2012-05-02 02:21:08.940 kclscrs: req=0 block=1/89233 2012-05-02 02:21:08.940676 : kjbcro[0x15c91.1 76896.0][5] *** 2012-05-02 02:21:08.940 kclscrs: req=0 typ=nowait-abort *** 2012-05-02 02:21:08.940 kclscrs: bid=1:3:1:0:f:21:0:0:10:0:0:0:1:2:4:1:20:0:0:0:c3:49:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:0:4:3:2:1:2:0:1f:0:4d:26:a3:52:0:0:0:0:c7:c:ca:62:c3:49:0:0:0:0:1:0:17:8e:47:76:1:2:dc:5:a9:fe:17:75:0:0:0:0:0:0:0:0:0:0:0:0:99:ed:0:0:0:0:0:0:10:0:0:0 2012-05-02 02:21:08.940799 : kjbcro[0x15c91.1 76896.0][5] 2012-05-02 02:21:08.940833 : GSIPC:GMBQ: buff 0xba0ee018, queue 0xbb79a7b8, pool 0x60013fa0, freeq 0, nxt 0xbb79a7b8, prv 0xbb79a7b8 2012-05-02 02:21:08.940859 : kjbsentscn[0x0.1ae28c][to 2] 2012-05-02 02:21:08.940870 : GSIPC:SENDM: send msg 0xba0ee088 dest x20001 seq 177810 type 36 tkts xff0000 mlen x1680198 2012-05-02 02:21:08.940976 : kjbmscr(0x15c91.1)reqid=0xa(req 0xa4ff30f8)(rinst 1)hldr 2(infosz 200)(lseq x2b8) 2012-05-02 02:21:08.941314 : GSIPC:KSXPCB: msg 0xba0ee088 status 30, type 36, dest 2, rcvr 1 *** 2012-05-02 02:21:08.941 kclwcrs: wait=0 tm=707 *** 2012-05-02 02:21:08.941 kclwcrs: got 1 blocks from ksxprcv 2012-05-02 02:21:08.941818 : kjbassume[0x15c91.1][sender 2][mymode x1][myrole x0][srole x0][flgs x0][spiscn 0x0.0][swscn 0x0.0] 2012-05-02 02:21:08.941852 : kjbrcvdscn[0x0.1ae28d][from 2][idx 2012-05-02 02:21:08.941871 : kjbrcvdscn[no bscn ??????????????SCN=[0x0.1ae28c]=1761932 Version?CR block, ????receive????Xcurrent Block??SCN=1ae28d=1761933,Instance 1???Xcurrent Block???build????????SCN=1761932?CR BLOCK, ????????Current block,?????????'gc current block 2-way'? ?????????????request current block,?????kjbcro;?????Instance 2?LMS???????Current Block: Instance 2 LMS trace: 2012-05-02 02:21:08.448743 : GSIPC:RCVD: ksxp msg 0x7f16e14a4398 sndr 1 seq 0.177810 type 36 tkts 0 2012-05-02 02:21:08.448778 : GSIPC:RCVD: watq msg 0x7f16e14a4398 sndr 1, seq 177810, type 36, tkts 0 2012-05-02 02:21:08.448798 : GSIPC:TKT: collect msg 0x7f16e14a4398 from 1 for rcvr -1, tickets 0 2012-05-02 02:21:08.448816 : kjbrcvdscn[0x0.1ae28c][from 1][idx 2012-05-02 02:21:08.448834 : kjbrcvdscn[no bscn <= rscn 0x0.1ae28c][from 1] 2012-05-02 02:21:08.448857 : GSIPC:TKT: dest (1:1) rtkt not acked 2  unassigned bufs 0  tkts 0  newbufs 0 2012-05-02 02:21:08.448875 : GSIPC:TKT: remove ctx dest (1:1) 2012-05-02 02:21:08.448970 : [kjmxmpm][type 36][seq 0.177810][msg 0x7f16e14a4398][from 1] 2012-05-02 02:21:08.448993 : kjbmpbast(0x15c91.1) reqid=0x6 (req 0xa4ff30f8)(reqinst 1)(reqid 10)(flags x0) *** 2012-05-02 02:21:08.449 kclcrrf: req=48054 block=1/89233 *** 2012-05-02 02:21:08.449 kcl_compress_block: compressed: 6 free space: 7680 2012-05-02 02:21:08.449085 : kjbsentscn[0x0.1ae28d][to 1] 2012-05-02 02:21:08.449142 : kjbdeliver[to 1][0xa4ff30f8][10][current 1] 2012-05-02 02:21:08.449164 : kjbmssch(reqlock 0xa4ff30f8,10)(to 1)(bsz 344) 2012-05-02 02:21:08.449183 : GSIPC:AMBUF: rcv buff 0x7f16e18bcec8, pool rcvbuf, rqlen 1102 *** 2012-05-02 02:21:08.449 kclccctx: cleanup copy 0x7f16e1d94838 *** 2012-05-02 02:21:08.449 kcltouched: touch seconds 3271 *** 2012-05-02 02:21:08.449 kclgrantlk: req=48054 2012-05-02 02:21:08.449347 : [kjmpmsgi:compl][type 36][msg 0x7f16e14a4398][seq 177810.0][qtime 0][ptime 1119] WAIT #0: nam='gcs remote message' ela= 568 waittime=1 poll=0 event=0 obj#=0 tim=1335939668449962 2012-05-02 02:21:08.450001 : GSIPC:RCVD: ksxp msg 0x7f16e1bb22a0 sndr 1 seq 0.177811 type 32 tkts 0 2012-05-02 02:21:08.450024 : GSIPC:RCVD: watq msg 0x7f16e1bb22a0 sndr 1, seq 177811, type 32, tkts 0 2012-05-02 02:21:08.450043 : GSIPC:TKT: collect msg 0x7f16e1bb22a0 from 1 for rcvr -1, tickets 0 2012-05-02 02:21:08.450060 : kjbrcvdscn[0x0.1ae28e][from 1][idx 2012-05-02 02:21:08.450078 : kjbrcvdscn[no bscn <= rscn 0x0.1ae28e][from 1] 2012-05-02 02:21:08.450097 : GSIPC:TKT: dest (1:1) rtkt not acked 3  unassigned bufs 0  tkts 0  newbufs 0 2012-05-02 02:21:08.450116 : GSIPC:TKT: remove ctx dest (1:1) 2012-05-02 02:21:08.450136 : [kjmxmpm][type 32][seq 0.177811][msg 0x7f16e1bb22a0][from 1] 2012-05-02 02:21:08.450155 : kjbmpocr(0xb0.6)seq 0x1,reqid=0x23e,(client 0x9fff7b58,0x1)(from 1)(lseq xdf4) ???Instance 2??LMS???,???build cr block,??????Instance 1?????Current Block??????Instance 2??v$cr_block_server??????LIGHT_WORKS?????current block transfer??????,??????? CR server? Light Work Rule(Light Work Rule?8i Cr Server?????????,?Remote LMS?? build CR????????,resource holder?LMS???????block,????CR build If creating the consistent read version block involves too much work (such as reading blocks from disk), then the holder sends the block to the requestor, and the requestor completes the CR fabrication. The holder maintains a fairness counter of CR requests. After the fairness threshold is reached, the holder downgrades it to lock mode.)? ??????? CR Request ????Current Block?? ???:??????class?block,CR server??????? ??undo block?? undo header block?CR quest, LMS????Current Block, ????? ???? ??????? block cleanout? CR  Version??????? ???????? data blocks, ??????? CR quest  & CR received?(???????Light Work Rule,LMS"??"), ??Current Block??DownConvert???S lock,??LMS???????ship??current version?block? ??????? , ?????? ,???????DownConvert?????”_fairness_threshold“???200,????Xcurrent Block?????Scurrent, ????LMS?????Current Version?Data Block: SQL> show parameter fair NAME TYPE VALUE ------------------------------------ ----------- ------------------------------ _fairness_threshold integer 200 Instance 1: SQL> update test set id=id+1 where id=4; 1 row updated. Instance 2: SQL> update test set id=id+1 where id=2; 1 row updated. SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 1 0 3 1838166 ?Instance 1? ????,? ??instance 2? v$cr_block_server?? instance 1 SQL> select * from test; ID ---------- 10 3 instance 2: SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 1 0 3 1883707 8 0 SQL> select * from test; ID ---------- 10 3 SQL> select state,cr_scn_bas from x$bh where file#=1 and dbablk=89233 and state!=0; STATE CR_SCN_BAS ---------- ---------- 1 0 3 1883707 8 0 ................... SQL> / STATE CR_SCN_BAS ---------- ---------- 2 0 3 1883707 3 1883695 repeat cr request on Instance 1 SQL> / STATE CR_SCN_BAS ---------- ---------- 8 0 3 1883707 3 1883695 ??????_fairness_threshold????????,?????200 ????????CR serve??Downgrade?lock, ????data block? CR Request????Receive? Current Block?

    Read the article

  • JRockit R28/JRockit Mission Control 4.0 is out!

    - by Marcus Hirt
    The next major release of JRockit is finally out! Here are some highlights: Includes the all new JRockit Flight Recorder – supersedes the old JRockit Runtime Analyser. The new flight recorder is inspired by the “black box” in airplanes. It uses a highly efficient recording engine and thread local buffers to capture data about the runtime and the application running in the JVM. It can be configured to always be on, so that whenever anything “interesting” happens, data can be dumped for some time back. Think of it as your own personal profiling time machine. Automatic shortest path calculation in Memleak – no longer any need for running around in circles when trying to find your way back to a thread root from an instance. Memleak can now show class loader related information and split graphs on a per class loader basis. More easily configured JMX agent – default port for both RMI Registry and RMI Server can be configured, and is by default the same, allowing easier configuration of firewalls. Up to 64 GB (was 4GB) compressed references. Per thread allocation profiling in the Management Console. Native Memory Tracking – it is now possible to track native memory allocations with very high resolution. The information can either be accessed using JRCMD, or the dedicated Native Memory Tracking experimental plug-in for the Management Console (alas only available for the upcoming 4.0.1 release). JRockit can now produce heap dumps in HPROF format. Cooperative suspension – JRockit is no longer using system signals for stopping threads, which could lead to hangs if signals were lost or blocked (for example bad NFS shares). Now threads check periodically to see if they are suspended. VPAT/Section 508 compliant JRMC – greatly improved keyboard navigation and screen reader support. See New and Noteworthy for more information. JRockit Mission Control 4.0.0 can be downloaded from here: http://www.oracle.com/technology/software/products/jrockit/index.html <shameless ad> There is even a book to go with JRMC 4.0.0/JRockit R28! http://www.packtpub.com/oracle-jrockit-the-definitive-guide/book/ </shameless ad>

    Read the article

  • LLBLGen Pro feature highlights: grouping model elements

    - by FransBouma
    (This post is part of a series of posts about features of the LLBLGen Pro system) When working with an entity model which has more than a few entities, it's often convenient to be able to group entities together if they belong to a semantic sub-model. For example, if your entity model has several entities which are about 'security', it would be practical to group them together under the 'security' moniker. This way, you could easily find them back, yet they can be left inside the complete entity model altogether so their relationships with entities outside the group are kept. In other situations your domain consists of semi-separate entity models which all target tables/views which are located in the same database. It then might be convenient to have a single project to manage the complete target database, yet have the entity models separate of each other and have them result in separate code bases. LLBLGen Pro can do both for you. This blog post will illustrate both situations. The feature is called group usage and is controllable through the project settings. This setting is supported on all supported O/R mapper frameworks. Situation one: grouping entities in a single model. This situation is common for entity models which are dense, so many relationships exist between all sub-models: you can't split them up easily into separate models (nor do you likely want to), however it's convenient to have them grouped together into groups inside the entity model at the project level. A typical example for this is the AdventureWorks example database for SQL Server. This database, which is a single catalog, has for each sub-group a schema, however most of these schemas are tightly connected with each other: adding all schemas together will give a model with entities which indirectly are related to all other entities. LLBLGen Pro's default setting for group usage is AsVisualGroupingMechanism which is what this situation is all about: we group the elements for visual purposes, it has no real meaning for the model nor the code generated. Let's reverse engineer AdventureWorks to an entity model. By default, LLBLGen Pro uses the target schema an element is in which is being reverse engineered, as the group it will be in. This is convenient if you already have categorized tables/views in schemas, like which is the case in AdventureWorks. Of course this can be switched off, or corrected on the fly. When reverse engineering, we'll walk through a wizard which will guide us with the selection of the elements which relational model data should be retrieved, which we can later on use to reverse engineer to an entity model. The first step after specifying which database server connect to is to select these elements. below we can see the AdventureWorks catalog as well as the different schemas it contains. We'll include all of them. After the wizard completes, we have all relational model data nicely in our catalog data, with schemas. So let's reverse engineer entities from the tables in these schemas. We select in the catalog explorer the schemas 'HumanResources', 'Person', 'Production', 'Purchasing' and 'Sales', then right-click one of them and from the context menu, we select Reverse engineer Tables to Entity Definitions.... This will bring up the dialog below. We check all checkboxes in one go by checking the checkbox at the top to mark them all to be added to the project. As you can see LLBLGen Pro has already filled in the group name based on the schema name, as this is the default and we didn't change the setting. If you want, you can select multiple rows at once and set the group name to something else using the controls on the dialog. We're fine with the group names chosen so we'll simply click Add to Project. This gives the following result:   (I collapsed the other groups to keep the picture small ;)). As you can see, the entities are now grouped. Just to see how dense this model is, I've expanded the relationships of Employee: As you can see, it has relationships with entities from three other groups than HumanResources. It's not doable to cut up this project into sub-models without duplicating the Employee entity in all those groups, so this model is better suited to be used as a single model resulting in a single code base, however it benefits greatly from having its entities grouped into separate groups at the project level, to make work done on the model easier. Now let's look at another situation, namely where we work with a single database while we want to have multiple models and for each model a separate code base. Situation two: grouping entities in separate models within the same project. To get rid of the entities to see the second situation in action, simply undo the reverse engineering action in the project. We still have the AdventureWorks relational model data in the catalog. To switch LLBLGen Pro to see each group in the project as a separate project, open the Project Settings, navigate to General and set Group usage to AsSeparateProjects. In the catalog explorer, select Person and Production, right-click them and select again Reverse engineer Tables to Entities.... Again check the checkbox at the top to mark all entities to be added and click Add to Project. We get two groups, as expected, however this time the groups are seen as separate projects. This means that the validation logic inside LLBLGen Pro will see it as an error if there's e.g. a relationship or an inheritance edge linking two groups together, as that would lead to a cyclic reference in the code bases. To see this variant of the grouping feature, seeing the groups as separate projects, in action, we'll generate code from the project with the two groups we just created: select from the main menu: Project -> Generate Source-code... (or press F7 ;)). In the dialog popping up, select the target .NET framework you want to use, the template preset, fill in a destination folder and click Start Generator (normal). This will start the code generator process. As expected the code generator has simply generated two code bases, one for Person and one for Production: The group name is used inside the namespace for the different elements. This allows you to add both code bases to a single solution and use them together in a different project without problems. Below is a snippet from the code file of a generated entity class. //... using System.Xml.Serialization; using AdventureWorks.Person; using AdventureWorks.Person.HelperClasses; using AdventureWorks.Person.FactoryClasses; using AdventureWorks.Person.RelationClasses; using SD.LLBLGen.Pro.ORMSupportClasses; namespace AdventureWorks.Person.EntityClasses { //... /// <summary>Entity class which represents the entity 'Address'.<br/><br/></summary> [Serializable] public partial class AddressEntity : CommonEntityBase //... The advantage of this is that you can have two code bases and work with them separately, yet have a single target database and maintain everything in a single location. If you decide to move to a single code base, you can do so with a change of one setting. It's also useful if you want to keep the groups as separate models (and code bases) yet want to add relationships to elements from another group using a copy of the entity: you can simply reverse engineer the target table to a new entity into a different group, effectively making a copy of the entity. As there's a single target database, changes made to that database are reflected in both models which makes maintenance easier than when you'd have a separate project for each group, with its own relational model data. Conclusion LLBLGen Pro offers a flexible way to work with entities in sub-models and control how the sub-models end up in the generated code.

    Read the article

  • Video on Architecture and Code Quality using Visual Studio 2012&ndash;interview with Marcel de Vries and Terje Sandstrom by Adam Cogan

    - by terje
    Find the video HERE. Adam Cogan did a great Web TV interview with Marcel de Vries and myself on the topics of architecture and code quality.  It was real fun participating in this session.  Although we know each other from the MVP ALM community,  Marcel, Adam and I haven’t worked together before. It was very interesting to see how we agreed on so many terms, and how alike we where thinking.  The basics of ensuring you have a good architecture and how you could document it is one thing.  Also, the same agreement on the importance of having a high quality code base, and how we used the Visual Studio 2012 tools, and some others (NDepend for example)  to measure and ensure that the code quality was where it should be.  As the tools, methods and thinking popped up during the interview it was a lot of “Hey !  I do that too!”.  The tools are not only for “after the fact” work, but we use them during the coding.  That way the tools becomes an integrated part of our coding work, and helps us to find issues we may have overlooked.  The video has a bunch of call outs, pinpointing important things to remember. These are also listed on the corresponding web page. I haven’t seen that touch before, but really liked this way of doing it – it makes it much easier to spot the highlights.  Titus Maclaren and Raj Dhatt from SSW have done a terrific job producing this video.  And thanks to Lei Xu for doing the camera and recording job.  Thanks guys ! Also, if you are at TechEd Amsterdam 2012, go and listen to Adam Cogan in his session on “A modern architecture review: Using the new code review tools” Friday 29th, 10.15-11.30 and Marcel de Vries session on “Intellitrace, what is it and how can I use it to my benefit” Wednesday 27th, 5-6.15 The highlights points out some important practices.  I’ll elaborate on a few of them here: Add instructions on how to compile the solution.  You do this by adding a text file with instructions to the solution, and keep it under source control.  These instructions should contain what is needed on top of a standard install of Visual Studio.  I do a lot of code reviews, and more often that not, I am not even able to compile the program, because they have used some tool or library that needs to be installed.  The same applies to any new developer who enters into the team, so do this to increase your productivity when the team changes, or a team member switches computer. Don’t forget to document what you have to configure on the computer, the IIS being a common one. The more automatic you can do this, the better.  Use NuGet to get down libraries. When the text document gets more than say, half a page, with a bunch of different things to do, convert it into a powershell script instead.  The metrics warning levels.  These are very conservatively set by Microsoft.  You rarely see anything but green, and besides, you should have color scales for each of the metrics.  I have a blog post describing a more appropriate set of levels, based on both research work and industry “best practices”.  The essential limits are: Cyclomatic complexity and coupling:  Higher numbers are worse On method levels: Green :  From 0 to 10 Yellow:  From 10 to 20  (some say 15).   Acceptable, but have a look to see if there is something unneeded here. Red: From 20 to 40:   Action required, get these down. Bleeding Red: Above 40   This is the real red alert.  Immediate action!  (My invention, as people have asked what do I do when I have cyclomatic complexity of 150.  The only answer I could think of was: RUN! ) Maintainability index:  Lower numbers are worse, scale from 0 to 100. On method levels: Green:  60 to 100 Yellow:  40 – 60.    You will always have methods here too, accept the higher ones, take a look at those who are down to the lower limit.  Check up against the other metrics.) Red:  20 – 40:  Action required, fix these. Bleeding red:  Below 20.  Immediate action required. When doing metrics analysis, you should leave the generated code out.  You do this by adding attributes, unfortunately Microsoft has “forgotten” to add these to all their stuff, so you might have to add them to some of the code.  It most cases it can be done so that it is not overwritten by a new round of code generation.  Take a look a my blog post here for details on how to do that. Class level metrics might also be useful, at least for coupling and maintenance.  But it is much more difficult to set any fixed limits on those.  Any metric aggregations on higher level tend to be pretty useless, as the number of methods vary pretty much, and there are little science on what number of methods can be regarded as good or bad.  NDepend have a recommendation, but they say it may vary too.  And in these days of data binding, the number might be pretty high, as properties counts as methods.  However, if you take the worst case situations, classes with more than 20 methods are suspicious, and coupling and cyclomatic complexity go red above 20, so any classes with more than 20x20 = 400 for these measures should be checked over. In the video we mention the SOLID principles, coined by “Uncle Bob” (Richard Martin). One of them, the Dependency Inversion principle we discuss in the video.  It is important to note that this principle is NOT on whether you should use a Dependency Inversion Container or not, it is about how you design the interfaces and interactions between your classes.  The Dependency Inversion Container is just one technique which is based on this principle, but which main purpose is to isolate things you would like to change at runtime, for example if you implement a plug in architecture.  Overuse of a Dependency Inversion Container is however, NOT a good thing.  It should be used for a purpose and not as a general DI solution.  The general DI solution and thinking however is useful far beyond the DIC.   You should always “program to an abstraction”, and not to the concreteness.  We also talk a bit about the GRASP patterns, a term coined by Craig Larman in his book Applying UML and design patterns. GRASP patterns stand for General Responsibility Assignment Software Patterns and describe fundamental principles of object design and responsibility assignment.  What I find great with these patterns is that they is another way to focus on the responsibility of a class.  One of the things I most often found that is broken in software designs, is that the class lack responsibility, and as a result there are a lot of classes mucking around in the internals of the other classes.  We also discuss the term “Code Smells”.  This term was invented by Kent Beck and Martin Fowler when they worked with Fowler’s “Refactoring” book. A code smell is a set of “bad” coding practices, which are the drivers behind a corresponding set of refactorings.  Here is a good list of the smells, and their corresponding refactor patterns. See also this.

    Read the article

  • Handling HTTP 404 Error in ASP.NET Web API

    - by imran_ku07
            Introduction:                     Building modern HTTP/RESTful/RPC services has become very easy with the new ASP.NET Web API framework. Using ASP.NET Web API framework, you can create HTTP services which can be accessed from browsers, machines, mobile devices and other clients. Developing HTTP services is now become more easy for ASP.NET MVC developer becasue ASP.NET Web API is now included in ASP.NET MVC. In addition to developing HTTP services, it is also important to return meaningful response to client if a resource(uri) not found(HTTP 404) for a reason(for example, mistyped resource uri). It is also important to make this response centralized so you can configure all of 'HTTP 404 Not Found' resource at one place. In this article, I will show you how to handle 'HTTP 404 Not Found' at one place.         Description:                     Let's say that you are developing a HTTP RESTful application using ASP.NET Web API framework. In this application you need to handle HTTP 404 errors in a centralized location. From ASP.NET Web API point of you, you need to handle these situations, No route matched. Route is matched but no {controller} has been found on route. No type with {controller} name has been found. No matching action method found in the selected controller due to no action method start with the request HTTP method verb or no action method with IActionHttpMethodProviderRoute implemented attribute found or no method with {action} name found or no method with the matching {action} name found.                                          Now, let create a ErrorController with Handle404 action method. This action method will be used in all of the above cases for sending HTTP 404 response message to the client.  public class ErrorController : ApiController { [HttpGet, HttpPost, HttpPut, HttpDelete, HttpHead, HttpOptions, AcceptVerbs("PATCH")] public HttpResponseMessage Handle404() { var responseMessage = new HttpResponseMessage(HttpStatusCode.NotFound); responseMessage.ReasonPhrase = "The requested resource is not found"; return responseMessage; } }                     You can easily change the above action method to send some other specific HTTP 404 error response. If a client of your HTTP service send a request to a resource(uri) and no route matched with this uri on server then you can route the request to the above Handle404 method using a custom route. Put this route at the very bottom of route configuration,  routes.MapHttpRoute( name: "Error404", routeTemplate: "{*url}", defaults: new { controller = "Error", action = "Handle404" } );                     Now you need handle the case when there is no {controller} in the matching route or when there is no type with {controller} name found. You can easily handle this case and route the request to the above Handle404 method using a custom IHttpControllerSelector. Here is the definition of a custom IHttpControllerSelector, public class HttpNotFoundAwareDefaultHttpControllerSelector : DefaultHttpControllerSelector { public HttpNotFoundAwareDefaultHttpControllerSelector(HttpConfiguration configuration) : base(configuration) { } public override HttpControllerDescriptor SelectController(HttpRequestMessage request) { HttpControllerDescriptor decriptor = null; try { decriptor = base.SelectController(request); } catch (HttpResponseException ex) { var code = ex.Response.StatusCode; if (code != HttpStatusCode.NotFound) throw; var routeValues = request.GetRouteData().Values; routeValues["controller"] = "Error"; routeValues["action"] = "Handle404"; decriptor = base.SelectController(request); } return decriptor; } }                     Next, it is also required to pass the request to the above Handle404 method if no matching action method found in the selected controller due to the reason discussed above. This situation can also be easily handled through a custom IHttpActionSelector. Here is the source of custom IHttpActionSelector,  public class HttpNotFoundAwareControllerActionSelector : ApiControllerActionSelector { public HttpNotFoundAwareControllerActionSelector() { } public override HttpActionDescriptor SelectAction(HttpControllerContext controllerContext) { HttpActionDescriptor decriptor = null; try { decriptor = base.SelectAction(controllerContext); } catch (HttpResponseException ex) { var code = ex.Response.StatusCode; if (code != HttpStatusCode.NotFound && code != HttpStatusCode.MethodNotAllowed) throw; var routeData = controllerContext.RouteData; routeData.Values["action"] = "Handle404"; IHttpController httpController = new ErrorController(); controllerContext.Controller = httpController; controllerContext.ControllerDescriptor = new HttpControllerDescriptor(controllerContext.Configuration, "Error", httpController.GetType()); decriptor = base.SelectAction(controllerContext); } return decriptor; } }                     Finally, we need to register the custom IHttpControllerSelector and IHttpActionSelector. Open global.asax.cs file and add these lines,  configuration.Services.Replace(typeof(IHttpControllerSelector), new HttpNotFoundAwareDefaultHttpControllerSelector(configuration)); configuration.Services.Replace(typeof(IHttpActionSelector), new HttpNotFoundAwareControllerActionSelector());         Summary:                       In addition to building an application for HTTP services, it is also important to send meaningful centralized information in response when something goes wrong, for example 'HTTP 404 Not Found' error.  In this article, I showed you how to handle 'HTTP 404 Not Found' error in a centralized location. Hopefully you will enjoy this article too.

    Read the article

  • Setup and Use SpecFlow BDD with DevExpress XAF

    - by Patrick Liekhus
    Let’s get started with using the SpecFlow BDD syntax for writing tests with the DevExpress XAF EasyTest scripting syntax.  In order for this to work you will need to download and install the prerequisites listed below.  Once they are installed follow the steps outlined below and enjoy. Prerequisites Install the following items: DevExpress eXpress Application Framework (XAF) found here SpecFlow found here Liekhus BDD/XAF Testing library found here Assumptions I am going to assume at this point that you have created your XAF application and have your Module, Win.Module and Win ready for usage.  You should have also set any attributes and/or settings as you see fit. Setup So where to start. Create a new testing project within your solution. I typically call this with a similar naming convention as used by XAF, my project name .FunctionalTests (i.e. AlbumManager.FunctionalTests). Add the following references to your project.  It should look like the reference list below. DevExpress.Data.v11.x DevExpress.Persistent.Base.v11.x DevExpress.Persistent.BaseImpl.v11.x DevExpress.Xpo.v11.2 Liekhus.Testing.BDD.Core Liekhus.Testing.BDD.DevExpress TechTalk.SpecFlow TestExecutor.v11.x (found in %Program Files%\DevExpress 2011.x\eXpressApp Framework\Tools\EasyTest Right click the TestExecutor reference and set the “Copy Local” setting to True.  This forces the TestExecutor executable to be available in the bin directory which is where the EasyTest script will be executed further down in the process. Add an Application Configuration File (app.config) to your test application.  You will need to make a few modifications to have SpecFlow generate Microsoft style unit tests.  First add the section handler for SpecFlow and then set your choice of testing framework.  I prefer MS Tests for my projects. Add the EasyTest configuration file to your project.  Add a new XML file and call it Config.xml. Open the properties window for the Config.xml file and set the “Copy to Ouput Directory” to “Copy Always”. You will setup the Config file according to the specifications of the EasyTest library my mapping to your executable and other settings.  You can find the details for the configuration of EasyTest here.  My file looks like this Create a new folder in your test project called “StepDefinitions”.  Add a new SpecFlow Step Definition file item under the StepDefinitions folder.  I typically call this class StepDefinition.cs. Have your step definition inherit from the Liekhus.Testing.BDD.DevExpress.StepDefinition class.  This will give you the default behaviors for your test in the next section. OK.  Now that we have done this series of steps, we will work on simplifying this.  This is an early preview of this new project and is not fully ready for consumption.  If you would like to experiment with it, please feel free.  Our goals are to make this a installable project on it’s own with it’s own project templates and default settings.  This will be coming in later versions.  Currently this project is in Alpha release. Let’s write our first test Remove the basic test that is created for you. We will not use the default test but rather create our own SpecFlow “Feature” files. Add a new item to your project and select the SpecFlow Feature file under C#. Name your feature file as you do your class files after the test they are performing. Writing a feature file uses the Cucumber syntax of Given… When… Then.  Think of it in these terms.  Givens are the pre-conditions for the test.  The Whens are the actual steps for the test being performed.  The Thens are the verification steps that confirm your test either passed or failed.  All of these steps are generated into a an EasyTest format and executed against your XAF project.  You can find more on the Cucumber syntax by using the Secret Ninja Cucumber Scrolls.  This document has several good styles of tests, plus you can get your fill of Chuck Norris vs Ninjas.  Pretty humorous document but full of great content. My first test is going to test the entry of a new Album into the application and is outlined below. The Feature section at the top is more for your documentation purposes.  Try to be descriptive of the test so that it makes sense to the next person behind you.  The Scenario outline is described in the Ninja Scrolls, but think of it as test template.  You can write one test outline and have multiple datasets (Scenarios) executed against that test.  Here are the steps of my test and their descriptions Given I am starting a new test – tells our test to create a new EasyTest file And (Given) the application is open – tells EasyTest to open our application defined in the Config.xml When I am at the “Albums” screen – tells XAF to navigate to the Albums list view And (When) I click the “New:Album” button – tells XAF to click the New Album button on the ribbon And (When) I enter the following information – tells XAF to find the field on the screen and put the value in that field And (When) I click the “Save and Close” button – tells XAF to click the “Save and Close” button on the detail window Then I verify results as “user” – tells the testing framework to execute the EasyTest as your configured user Once you compile and prepare your tests you should see the following in your Test View.  For each of your CreateNewAlbum lines in your scenarios, you will see a new test ready to execute. From here you will use your testing framework of choice to execute the test.  This in turn will execute the EasyTest framework to call back into your XAF application and test your business application. Again, please remember that this is an early preview and we are still working out the details.  Please let us know if you have any comments/questions/concerns. Thanks and happy testing.

    Read the article

  • Stretching an ADF Faces Component to (near) 100%

    - by Christian David Straub
    In the past, many users would want their component to stretch to fill 100% of a horizontal area. However, to account for scrollbars that may or may not have been there, they would set the percentage to 98%, etc.A much better way to do this is to use the new "AFStretchWidth" style class, which will do this automatically for you.For instance, avoid this:<af:foo inlineStyle="98%" />and instead do this:<af:foo styleClass="AFStretchWidth" />You can learn more about ADF Faces layout management here.

    Read the article

  • WP7 Tips–Part I– Media File Coding Techniques to help pass the Windows Phone 7 Marketplace Certification Requirements

    - by seaniannuzzi
    Overview Developing an application that plays media files on a Windows Phone 7 Device seems fairly straight forward.  However, what can make this a bit frustrating are the necessary requirements in order to pass the WP7 marketplace requirements so that your application can be published.  If you are new to this development, be aware of these common challenges that are likely to be made.  Below are some techniques and recommendations on how optimize your application to handle playing MP3 and/or WMA files that needs to adhere to the marketplace requirements.   Windows Phone 7 Certification Requirements Windows Phone 7 Developers Blog   Some common challenges are: Not prompting the user if another media file is playing in the background before playing your media file Not allowing the user to control the volume Not allowing the user to mute the sound Not allowing the media to be interrupted by a phone call  To keep this as simple as possible I am only going to focus on what “not to do” and what “to do” in order to implement a simple media solution. Things you will need or may be useful to you before you begin: Visual Studio 2010 Visual Studio 2010 Feature Packs Windows Phone 7 Developer Tools Visual Studio 2010 Express for Windows Phone Windows Phone Emulator Resources Silverlight 4 Tools For Visual Studio XNA Game Studio 4.0 Microsoft Expression Blend for Windows Phone Note: Please keep in mind you do not need all of these downloaded and installed, it is just easier to have all that you need now rather than add them on later.   Objective Summary Create a Windows Phone 7 – Windows Media Sample Application.  The application will implement many of the required features in order to pass the WP7 marketplace certification requirements in order to publish an application to WP7’s marketplace. (Disclaimer: I am not trying to indicate that this application will always pass as the requirements may change or be updated)   Step 1: – Create a New Windows Phone 7 Project   Step 2: – Update the Title and Application Name of your WP7 Application For this example I changed: the Title to: “DOTNETNUZZI WP7 MEDIA SAMPLE - v1.00” and the Page Title to:  “media magic”. Note: I also updated the background.   Step 3: – XAML - Media Element Preparation and Best Practice Before we begin the next step I just wanted to point out a few things that you should not do as a best practice when developing an application for WP7 that is playing music.  Please keep in mind that these requirements are not the same if you are playing Sound Effects and are geared towards playing media in the background.   If you have coded this – be prepared to change it:   To avoid a failure from the market place remove all of your media source elements from your XAML or simply create them dynamically.  To keep this simple we will remove the source and set the AutoPlay property to false to ensure that there are no media elements are active when the application is started. Proper example of the media element with No Source:   Some Additional Settings - Add XAML Support for a Mute Button   Step 4: – Boolean to handle toggle of Mute Feature Step 5: – Add Event Handler for Main Page Load   Step 6: – Add Reference to the XNA Framework   Step 7: – Add two Using Statements to Resolve the Namespace of Media and the Application Bar using Microsoft.Xna.Framework.Media; using Microsoft.Phone.Shell;   Step 8: – Add the Method to Check the Media State as Shown Below   Step 9: – Add Code to Mute the Media File Step 10: – Add Code to Play the Media File //if the state of the media has been checked you are good to go. media_sample.Play(); Note: If we tried to perform this operation at this point you will receive the following error: System.InvalidOperationException was unhandled Message=FrameworkDispatcher.Update has not been called. Regular FrameworkDispatcher.Update calls are necessary for fire and forget sound effects and framework events to function correctly. See http://go.microsoft.com/fwlink/?LinkId=193853 for details. StackTrace:        at Microsoft.Xna.Framework.FrameworkDispatcher.AddNewPendingCall(ManagedCallType callType, UInt32 arg)        at Microsoft.Xna.Framework.UserAsyncDispatcher.HandleManagedCallback(ManagedCallType managedCallType, UInt32 managedCallArgs) at Microsoft.Xna.Framework.UserAsyncDispatcher.AsyncDispatcherThreadFunction()            It is not recommended that you just add the FrameworkDispatcher.Update(); call before playing the media file. It is recommended that you implement the following class to your solution and implement this class in the app.xaml.cs file.   Step 11: – Add FrameworkDispatcher Features I recommend creating a class named XNAAsyncDispatcher and adding the following code:   After you have added the code accordingly, you can now implement this into your app.xaml.cs file as highlighted below.   Note:  If you application sound file is not playing make sure you have the proper “Build Action” set such as Content.   Running the Sample Now that we have some of the foundation created you should be able to run the application successfully.  When the application launches your sound options should be set accordingly when the “checkMediaState” method is called.  As a result the application will properly setup the media options and/or alert the user accordinglyper the certification requirements.  In addition, the sample also shows a quick way to mute the sound in your application by simply removing the URI source of the media file.  If everything successfully compiled the application should look similar to below.                 <sound playing>   Summary At this point we have a fully functional application that provides techniques on how to avoid some common challenges when working with media files and developing applications for Windows Phone 7.  The techniques mentioned above should make things a little easier and helpful in getting your WP7 application approved and published on the Marketplace.  The next blog post will be titled: WP7 Tips–Part II - How to write code that will pass the Windows Phone 7 Marketplace Requirements for Themes (light and dark). If anyone has any questions or comments please comment on this blog. 

    Read the article

  • Silverlight for Windows Embedded Tutorial (step 5 and a bit of Windows Phone 7)

    - by Valter Minute
    If you haven’t spent the last week in the middle of the Sahara desert or traveling on a sled in the north pole area you should have heard something about the launch of Windows Phone 7 Series (or Windows Phone Series 7, or Windows Series Phone 7 or something like that). Even if you are in the middle of the desert or somewhere around the north pole you may have been reached by the news, since it seems that WP7S (using the full name will kill my available bandwidth!) is generating a lot of buzz in the development and IT communities. One of the most important aspects of this new platform is that it will be programmed using a new set of tools and frameworks, completely different from the ones used on older releases of Windows Mobile (or SmartPhone, or PocketPC or whatever…). WP7S applications can be developed using Silverlight or XNA. If you want to learn something more about WP7S development you can download the preview of Charles Petzold’s book about it: http://www.charlespetzold.com/phone/index.html Charles Petzold is also the author of “Programming Windows”, the first book I ever read about programming on Windows (it was Windows 3.0 at that time!). The fact that even I was able to learn how to develop Windows application is a proof of the quality of Petzold’s work. This book is up to his standards and the 150pages preview is already rich in technical contents without being boring or complicated to understand. I may be able to become a Windows Phone developer thanks to mr. Petzold. Mr. Petzold uses some nice samples to introduce the basic concepts of Silverlight development on WP7S. On this new platform you’ll use managed code to develop your application, so those samples can’t be ported on Windows CE R3 as they are, but I would like to take one of the first samples (called “SilverlightTapHello1”) and adapt it to Silverlight for Windows Embedded to show that even plain old native code can be used to develop “cool” user interfaces! The sample shows the standard WP7S title header and a textbox with an hello world message inside it. When the user touches the textbox, it will change its color. When the user touches the background (Grid) behind it, its default color (plain old White) will be restored. Let’s see how we can implement the same features on our embedded device! I took the XAML code of the sample (you can download the book samples here: http://download.microsoft.com/download/1/D/B/1DB49641-3956-41F1-BAFA-A021673C709E/CodeSamples_DRAFTPreview_ProgrammingWindowsPhone7Series.zip) and changed it a little bit to remove references to WP7S or managed runtime. If you compare the resulting files you will see that I was able to keep all the resources inside the App.xaml files and the structure of  MainPage.XAML almost intact. This is the Silverlight for Windows Embedded version of MainPage.XAML: <UserControl x:Class="SilverlightTapHello1.MainPage" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:phoneNavigation="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Navigation" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="800" FontFamily="{StaticResource PhoneFontFamilyNormal}" FontSize="{StaticResource PhoneFontSizeNormal}" Foreground="{StaticResource PhoneForegroundBrush}" Width="640" Height="480">   <Grid x:Name="LayoutRoot" Background="{StaticResource PhoneBackgroundBrush}"> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> </Grid.RowDefinitions>   <!--TitleGrid is the name of the application and page title--> <Grid x:Name="TitleGrid" Grid.Row="0"> <TextBlock Text="SILVERLIGHT TAP HELLO #1" x:Name="textBlockPageTitle" Style="{StaticResource PhoneTextPageTitle1Style}"/> <TextBlock Text="main page" x:Name="textBlockListTitle" Style="{StaticResource PhoneTextPageTitle2Style}"/> </Grid>   <!--ContentGrid is empty. Place new content here--> <Grid x:Name="ContentGrid" Grid.Row="1" MouseLeftButtonDown="ContentGrid_MouseButtonDown" Background="{StaticResource PhoneBackgroundBrush}"> <TextBlock x:Name="TextBlock" Text="Hello, Silverlight for Windows Embedded!" HorizontalAlignment="Center" VerticalAlignment="Center" /> </Grid> </Grid> </UserControl> If you compare it to the WP7S sample (not reported here to avoid any copyright issue) you’ll notice that I had to replace the original phoneNavigation:PhoneApplicationPage with UserControl as the root node. This make sense because there is not support for phone applications on CE 6. I also had to specify width and height of my main page (on the WP7S device this will be adjusted by the OS) and I had to replace the multi-touch event handler with the MouseLeftButtonDown event (no multitouch support for Windows CE R3, still). I also changed the hello message, of course. I used XAML2CPP to generate the boring part of our application and then added the initialization code to WinMain: int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { if (!XamlRuntimeInitialize()) return -1;   HRESULT retcode;   IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return -1; XRXamlSource dictsrc;   dictsrc.SetResource(hInstance,TEXT("XAML"),IDR_XAML_App);   if (FAILED(retcode=app->LoadResourceDictionary(&dictsrc,NULL))) return -1;   MainPage page;   if (FAILED(page.Init(hInstance,app))) return -1;   UINT exitcode;   if (FAILED(page.GetVisualHost()->StartDialog(&exitcode))) return -1;   return exitcode; }   You may have noticed that there is something different from the previous samples. I added the code to load a resource dictionary. Resources are an important feature of XAML that allows you to define some values that could be replaced inside any XAML file loaded by the runtime. You can use resources to define custom styles for your fonts, backgrounds, controls etc. and to support internationalization, by providing different strings for different languages. The rest of our WinMain isn’t that different. It creates an instances of our MainPage object and displays it. The MainPage class implements an event handler for the MouseLeftButtonDown event of the ContentGrid: class MainPage : public TMainPage<MainPage> { public:   HRESULT ContentGrid_MouseButtonDown(IXRDependencyObject* source,XRMouseButtonEventArgs* args) { HRESULT retcode; IXRSolidColorBrushPtr brush; IXRApplicationPtr app;   if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode;   if (FAILED(retcode=app->CreateObject(IID_IXRSolidColorBrush,&brush))) return retcode;   COLORREF color=RGBA(0xff,0xff,0xff,0xff);   if (args->pOriginalSource==TextBlock) color=RGBA(rand()&0xFF,rand()&0xFF,rand()&0xFF,0xFF);   if (FAILED(retcode=brush->SetColor(color))) return retcode;   if (FAILED(retcode=TextBlock->SetForeground(brush))) return retcode; return S_OK; } }; As you can see this event is generated when a used clicks inside the grid or inside one of the objects it contains. Since our TextBlock is inside the grid, we don’t need to provide an event handler for its MouseLeftButtonDown event. We can just use the pOriginalSource member of the event arguments to check if the event was generated inside the textblock. If the event was generated inside the grid we create a white brush,if it’s inside the textblock we create some randomly colored brush. Notice that we need to use the RGBA macro to create colors, specifying also a transparency value for them. If we use the RGB macro the resulting color will have its Alpha channel set to zero and will be transparent. Using the SetForeground method we can change the color of our control. You can compare this to the managed code that you can find at page 40-41 of Petzold’s preview book and you’ll see that the native version isn’t much more complex than the managed one. As usual you can download the full code of the sample here: http://cid-9b7b0aefe3514dc5.skydrive.live.com/self.aspx/.Public/SilverlightTapHello1.zip And remember to pre-order Charles Petzold’s “Programming Windows Phone 7 series”, I bet it will be a best-seller! Technorati Tags: Silverlight for Windows Embedded,Windows CE

    Read the article

  • Error trapping for a missing data source in a Spring MVC / Spring JDBC web app [migrated]

    - by Geeb
    I have written a web app that uses Spring MVC libraries and Spring JDBC to connect to an Oracle DB. (I don't use any ORM type libraries as I create stored procedures on Oracle that do my stuff and I'm quite happy with that.) I use a connection pool to Oracle managed by the Tomcat container The app generally works absolutely fine by the way! BUT... I noticed the other day when I tried to set up the app on another Tomcat instance that I had forgotten to configure the connection pool and obviously the app could not get hold of an org.apache.commons.dbcp.BasicDataSource object, so it crashed. I define the pool params in the tomcat "context.conf" In my "web.xml" I have: <servlet> <servlet-name>appServlet</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/Spring/appServlet/servlet-context.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>appServlet</servlet-name> <!-- Map *everything* to appServlet --> <url-pattern>/</url-pattern> </servlet-mapping> <resource-ref> <description>Oracle Datasource example</description> <res-ref-name>jdbc/ora1</res-ref-name> <res-type>org.apache.commons.dbcp.BasicDataSource</res-type> <res-auth>Container</res-auth> </resource-ref> And I have a Spring "servlet-context.xml" where JNDI is used to map the data source object provided by the connection pool to a Spring bean with the ID of "dataSource": <jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/ora1" resource-ref="true" /> Here's the question: Where do I trap the case where the database cannot be accessed for whatever reason? I don't want the user to see a yard-and-a-half of Java stack trace in their browser, rather a nicer message that tells them there is a database problem etc. It seems that my app tries to configure the "dataSource" bean (in "servlet-context.xml") before any code has tested it can actually provide a dataSource object from the pool?! Maybe I'm not fully understanding exactly what is going on in these stages of the app firing up ... Thanks for any advice!

    Read the article

  • Code Trivia #5

    - by João Angelo
    A quick one inspired by real life broken code. What’s wrong in this piece of code? class Planet { public Planet() { this.Initialize(); } public Planet(string name) : this() { this.Name = name; } private string name = "Unspecified"; public string Name { get { return name; } set { name = value; } } private void Initialize() { Console.Write("Planet {0} initialized.", this.Name); } }

    Read the article

  • A small, intra-app Object to String Serializer

    - by Rick Strahl
    On a few occasions I've needed a very compact serializer for small and simple, flat object serialization, typically for storage in Cookies or a FormsAuthentication ticket in ASP.NET. XML and JSON serialization are too verbose for those scenarios so a simple property serializer that strings together the values was needed. Originally I did this by hand, but here is a class that automates the process.

    Read the article

  • When OneTug Just Isn&rsquo;t Enough&hellip;

    - by onefloridacoder
    I stole that from the back of a T-shirt I saw at the Orlando Code Camp 2010.  This was my first code camp and my first time volunteering for an event like this as well.  It was an awesome day.  I cannot begin to count the “aaahh”, “I did-not-know I could do that”, in the crowds and for myself.  I think it was a great day of learning for everyone at all levels.  All of the presenters were different and provided great insights into the topics they were presenting.  Here’s a list of the ones that I attended. KodeFuGuru, “Pirates vs. Ninjas” He touched on many good topics to relax some of the ways we think when we are writing out code, and still looks good, readable, etc.  As he pointed out in all of his examples, we might not always realize everything that’s going on under the covers.  He exposed a bug in his own code, and verbalized the mental gymnastics he went through when he knew there was something wrong with one of his IEnumerable implementations.  For me, it was great to hear that someone else labors over these gut reactions to code quickly snapped together, to the point that we rush to the refactor stage to fix what’s bothering us – and learn.  He has some content on extension methods that was very interesting.  My “that is so cool” moment was when he swapped out AddEntity method on an entity class and used a With extension method instead.  Some of the LINQ scales fell off my eyes at that moment, and I realized my own code could be a lot more powerful (and readable) if incorporate a few of these examples at the appropriate times.  And he cautioned as well… “don’t go crazy with this stuff”, there’s a place and time for everything.  One of his examples demo’d toward the end of the talk is on his sight where he’s chaining methods together, cool stuff. Quotes I liked: “Extension Methods - Extension methods to put features back on the model type, without impacting the type.” “Favor Declarative Code” – Check out the ? and ?? operators if you’re not already using them. “Favor Fluent Code” “Avoid Pirate Ninja Zombies!  If you see one run!” I’m definitely going to be looking at “Extract Projection” when I get into VS2010. BDD 101 – Sean Chambers http://github.com/schambers This guy had a whole host of gremlins against him, final score Sean 5, Gremlins 1.  He ran the code samples from his github repo  in the code github code viewer since the PC they school gave him to use didn’t have VS installed. He did a great job of converting the grammar between BDD and TDD, and how this style of development can be used in integration tests as well as the different types of gated builds on a CI box – he didn’t go into a discussion around CI, but we could infer that it could work. Like when we use WSSF, it does cause a class explosion to happen however the amount of code per class it limit to just covering the concern at hand – no more, no less.  As in “When I as a <Role>, expect {something} to happen, because {}”  This keeps us (the developer) from gold plating our solutions and creating less waste.  He basically keeps the code that prove out the requirement to two lines of code.  Nice. He uses SpecUnit to merge this grammar into his .NET projects and gave an overview on how this ties into writing his own BDD tests.  Some folks were familiar with Given / When / Then as story acceptance criteria and here’s how he mapped it: “Given <Context>  When <Something Happens> Then <I expect...>”  There are a few base classes and overrides in the SpecUnit framework that help with setting up the context for each test which looked very handy. Successfully Running Your Own Coding Business The speaker ran through a list of items that sounded like common sense stuff LLC, banking, separating expenses, etc.  Then moved into role playing with business owners and an ISV.  That was pretty good stuff, it pays to be a good listener all of the time even if your client is sitting on the other side of the phone tearing you head off for you – but that’s all it is, and get used to it its par for the course.  Oh, yeah always answer the phone was one simple thing that you can do to move  your business forward.  But like Cory Foy tweeted this week, “If you owe me a lot of money, don’t have a message that says your away for five weeks skiing in Colorado.”  Lots of food for thought that’s on my list of “todo’s and to-don’ts”. Speaker Idol Next, I had the pleasure of helping Russ Fustino tape this part of Code Camp as my primary volunteer opportunity that day.  You remember Russ, “know the code” from the awesome Russ’ Tool Shed series.  He did a great job orchestrating and capturing the Speaker Idol finals.   So I didn’t actually miss any sessions, but was able to see three back to back in one setting.  The idol finalists gave a 10 minute talk and very deep subjects, but different styles of talks.  No one walked away empty handed for jobs very well done.  Russ has details on his site.  The pictures and  video captured is supposed to be published on Channel 9 at a later date.  It was also a valuable experience to see what makes technical speakers effective in their talks.  I picked up quite a few speaking tips from what I heard from the judges and contestants. Design For Developers – Diane Leeper If you are a great developer, you’re probably a lousy designer.  Diane didn’t come to poke holes in what we think we can do with UI layout and design, but she provided some tools we can use to figure out metaphors for visualizing data.  If you need help with that check out Silverlight Pivot – that’s what she was getting at.  I was first introduced to her at one of John Papa’s talks last year at a Lakeland User Group meeting and she’s very passionate about design.  She was able to discuss different elements of Pivot, while to a developer is just looked cool. I believe she was providing the deck from her talk to folks after her talk, so send her an email if you’re interested.   She says she can talk about design for hours and hours – we all left that session believing her.   Rinse and Repeat Orlando Code Camp 2010 was awesome, and would totally do it again.  There were lots of folks from my shop there, and some that have left my shop to go elsewhere.  So it was a reunion of sorts and a great celebration for the simple fact that its great to be a developer and there’s a community that supports and recognizes it as well.  The sponsors were generous and the organizers were very tired, namely Esteban Garcia and Will Strohl who were responsible for making a lot of this magic happen.  And if you don’t believe me, check out the chatter on Twitter.

    Read the article

  • Abstracting away the type of a property

    - by L. De Leo
    In Python luckily most of the times you don't have to write getters and setters to get access to class properties. That said sometimes you'll have to remember that a certain property is a list or whatnot and a property would save you there by abstracting the type and providing a setter to add something to such list for example rather than exposing the list directly. Where do you draw the line between exposing the type directly or wrapping its access in a property? What's the general "pythonic" advice?

    Read the article

  • Scaling-out Your Services by Message Bus based WCF Transport Extension &ndash; Part 1 &ndash; Background

    - by Shaun
    Cloud computing gives us more flexibility on the computing resource, we can provision and deploy an application or service with multiple instances over multiple machines. With the increment of the service instances, how to balance the incoming message and workload would become a new challenge. Currently there are two approaches we can use to pass the incoming messages to the service instances, I would like call them dispatcher mode and pulling mode.   Dispatcher Mode The dispatcher mode introduces a role which takes the responsible to find the best service instance to process the request. The image below describes the sharp of this mode. There are four clients communicate with the service through the underlying transportation. For example, if we are using HTTP the clients might be connecting to the same service URL. On the server side there’s a dispatcher listening on this URL and try to retrieve all messages. When a message came in, the dispatcher will find a proper service instance to process it. There are three mechanism to find the instance: Round-robin: Dispatcher will always send the message to the next instance. For example, if the dispatcher sent the message to instance 2, then the next message will be sent to instance 3, regardless if instance 3 is busy or not at that moment. Random: Dispatcher will find a service instance randomly, and same as the round-robin mode it regardless if the instance is busy or not. Sticky: Dispatcher will send all related messages to the same service instance. This approach always being used if the service methods are state-ful or session-ful. But as you can see, all of these approaches are not really load balanced. The clients will send messages at any time, and each message might take different process duration on the server side. This means in some cases, some of the service instances are very busy while others are almost idle. For example, if we were using round-robin mode, it could be happened that most of the simple task messages were passed to instance 1 while the complex ones were sent to instance 3, even though instance 1 should be idle. This brings some problem in our architecture. The first one is that, the response to the clients might be longer than it should be. As it’s shown in the figure above, message 6 and 9 can be processed by instance 1 or instance 2, but in reality they were dispatched to the busy instance 3 since the dispatcher and round-robin mode. Secondly, if there are many requests came from the clients in a very short period, service instances might be filled by tons of pending tasks and some instances might be crashed. Third, if we are using some cloud platform to host our service instances, for example the Windows Azure, the computing resource is billed by service deployment period instead of the actual CPU usage. This means if any service instance is idle it is wasting our money! Last one, the dispatcher would be the bottleneck of our system since all incoming messages must be routed by the dispatcher. If we are using HTTP or TCP as the transport, the dispatcher would be a network load balance. If we wants more capacity, we have to scale-up, or buy a hardware load balance which is very expensive, as well as scaling-out the service instances. Pulling Mode Pulling mode doesn’t need a dispatcher to route the messages. All service instances are listening to the same transport and try to retrieve the next proper message to process if they are idle. Since there is no dispatcher in pulling mode, it requires some features on the transportation. The transportation must support multiple client connection and server listening. HTTP and TCP doesn’t allow multiple clients are listening on the same address and port, so it cannot be used in pulling mode directly. All messages in the transportation must be FIFO, which means the old message must be received before the new one. Message selection would be a plus on the transportation. This means both service and client can specify some selection criteria and just receive some specified kinds of messages. This feature is not mandatory but would be very useful when implementing the request reply and duplex WCF channel modes. Otherwise we must have a memory dictionary to store the reply messages. I will explain more about this in the following articles. Message bus, or the message queue would be best candidate as the transportation when using the pulling mode. First, it allows multiple application to listen on the same queue, and it’s FIFO. Some of the message bus also support the message selection, such as TIBCO EMS, RabbitMQ. Some others provide in memory dictionary which can store the reply messages, for example the Redis. The principle of pulling mode is to let the service instances self-managed. This means each instance will try to retrieve the next pending incoming message if they finished the current task. This gives us more benefit and can solve the problems we met with in the dispatcher mode. The incoming message will be received to the best instance to process, which means this will be very balanced. And it will not happen that some instances are busy while other are idle, since the idle one will retrieve more tasks to make them busy. Since all instances are try their best to be busy we can use less instances than dispatcher mode, which more cost effective. Since there’s no dispatcher in the system, there is no bottleneck. When we introduced more service instances, in dispatcher mode we have to change something to let the dispatcher know the new instances. But in pulling mode since all service instance are self-managed, there no extra change at all. If there are many incoming messages, since the message bus can queue them in the transportation, service instances would not be crashed. All above are the benefits using the pulling mode, but it will introduce some problem as well. The process tracking and debugging become more difficult. Since the service instances are self-managed, we cannot know which instance will process the message. So we need more information to support debug and track. Real-time response may not be supported. All service instances will process the next message after the current one has done, if we have some real-time request this may not be a good solution. Compare with the Pros and Cons above, the pulling mode would a better solution for the distributed system architecture. Because what we need more is the scalability, cost-effect and the self-management.   WCF and WCF Transport Extensibility Windows Communication Foundation (WCF) is a framework for building service-oriented applications. In the .NET world WCF is the best way to implement the service. In this series I’m going to demonstrate how to implement the pulling mode on top of a message bus by extending the WCF. I don’t want to deep into every related field in WCF but will highlight its transport extensibility. When we implemented an RPC foundation there are many aspects we need to deal with, for example the message encoding, encryption, authentication and message sending and receiving. In WCF, each aspect is represented by a channel. A message will be passed through all necessary channels and finally send to the underlying transportation. And on the other side the message will be received from the transport and though the same channels until the business logic. This mode is called “Channel Stack” in WCF, and the last channel in the channel stack must always be a transport channel, which takes the responsible for sending and receiving the messages. As we are going to implement the WCF over message bus and implement the pulling mode scaling-out solution, we need to create our own transport channel so that the client and service can exchange messages over our bus. Before we deep into the transport channel, let’s have a look on the message exchange patterns that WCF defines. Message exchange pattern (MEP) defines how client and service exchange the messages over the transportation. WCF defines 3 basic MEPs which are datagram, Request-Reply and Duplex. Datagram: Also known as one-way, or fire-forgot mode. The message sent from the client to the service, and no need any reply from the service. The client doesn’t care about the message result at all. Request-Reply: Very common used pattern. The client send the request message to the service and wait until the reply message comes from the service. Duplex: The client sent message to the service, when the service processing the message it can callback to the client. When callback the service would be like a client while the client would be like a service. In WCF, each MEP represent some channels associated. MEP Channels Datagram IInputChannel, IOutputChannel Request-Reply IRequestChannel, IReplyChannel Duplex IDuplexChannel And the channels are created by ChannelListener on the server side, and ChannelFactory on the client side. The ChannelListener and ChannelFactory are created by the TransportBindingElement. The TransportBindingElement is created by the Binding, which can be defined as a new binding or from a custom binding. For more information about the transport channel mode, please refer to the MSDN document. The figure below shows the transport channel objects when using the request-reply MEP. And this is the datagram MEP. And this is the duplex MEP. After investigated the WCF transport architecture, channel mode and MEP, we finally identified what we should do to extend our message bus based transport layer. They are: Binding: (Optional) Defines the channel elements in the channel stack and added our transport binding element at the bottom of the stack. But we can use the build-in CustomBinding as well. TransportBindingElement: Defines which MEP is supported in our transport and create the related ChannelListener and ChannelFactory. This also defines the scheme of the endpoint if using this transport. ChannelListener: Create the server side channel based on the MEP it’s. We can have one ChannelListener to create channels for all supported MEPs, or we can have ChannelListener for each MEP. In this series I will use the second approach. ChannelFactory: Create the client side channel based on the MEP it’s. We can have one ChannelFactory to create channels for all supported MEPs, or we can have ChannelFactory for each MEP. In this series I will use the second approach. Channels: Based on the MEPs we want to support, we need to implement the channels accordingly. For example, if we want our transport support Request-Reply mode we should implement IRequestChannel and IReplyChannel. In this series I will implement all 3 MEPs listed above one by one. Scaffold: In order to make our transport extension works we also need to implement some scaffold stuff. For example we need some classes to send and receive message though out message bus. We also need some codes to read and write the WCF message, etc.. These are not necessary but would be very useful in our example.   Message Bus There is only one thing remained before we can begin to implement our scaling-out support WCF transport, which is the message bus. As I mentioned above, the message bus must have some features to fulfill all the WCF MEPs. In my company we will be using TIBCO EMS, which is an enterprise message bus product. And I have said before we can use any message bus production if it’s satisfied with our requests. Here I would like to introduce an interface to separate the message bus from the WCF. This allows us to implement the bus operations by any kinds bus we are going to use. The interface would be like this. 1: public interface IBus : IDisposable 2: { 3: string SendRequest(string message, bool fromClient, string from, string to = null); 4:  5: void SendReply(string message, bool fromClient, string replyTo); 6:  7: BusMessage Receive(bool fromClient, string replyTo); 8: } There are only three methods for the bus interface. Let me explain one by one. The SendRequest method takes the responsible for sending the request message into the bus. The parameters description are: message: The WCF message content. fromClient: Indicates if this message was came from the client. from: The channel ID that this message was sent from. The channel ID will be generated when any kinds of channel was created, which will be explained in the following articles. to: The channel ID that this message should be received. In Request-Reply and Duplex MEP this is necessary since the reply message must be received by the channel which sent the related request message. The SendReply method takes the responsible for sending the reply message. It’s very similar as the previous one but no “from” parameter. This is because it’s no need to reply a reply message again in any MEPs. The Receive method takes the responsible for waiting for a incoming message, includes the request message and specified reply message. It returned a BusMessage object, which contains some information about the channel information. The code of the BusMessage class is 1: public class BusMessage 2: { 3: public string MessageID { get; private set; } 4: public string From { get; private set; } 5: public string ReplyTo { get; private set; } 6: public string Content { get; private set; } 7:  8: public BusMessage(string messageId, string fromChannelId, string replyToChannelId, string content) 9: { 10: MessageID = messageId; 11: From = fromChannelId; 12: ReplyTo = replyToChannelId; 13: Content = content; 14: } 15: } Now let’s implement a message bus based on the IBus interface. Since I don’t want you to buy and install the TIBCO EMS or any other message bus products, I will implement an in process memory bus. This bus is only for test and sample purpose. It can only be used if the service and client are in the same process. Very straightforward. 1: public class InProcMessageBus : IBus 2: { 3: private readonly ConcurrentDictionary<Guid, InProcMessageEntity> _queue; 4: private readonly object _lock; 5:  6: public InProcMessageBus() 7: { 8: _queue = new ConcurrentDictionary<Guid, InProcMessageEntity>(); 9: _lock = new object(); 10: } 11:  12: public string SendRequest(string message, bool fromClient, string from, string to = null) 13: { 14: var entity = new InProcMessageEntity(message, fromClient, from, to); 15: _queue.TryAdd(entity.ID, entity); 16: return entity.ID.ToString(); 17: } 18:  19: public void SendReply(string message, bool fromClient, string replyTo) 20: { 21: var entity = new InProcMessageEntity(message, fromClient, null, replyTo); 22: _queue.TryAdd(entity.ID, entity); 23: } 24:  25: public BusMessage Receive(bool fromClient, string replyTo) 26: { 27: InProcMessageEntity e = null; 28: while (true) 29: { 30: lock (_lock) 31: { 32: var entity = _queue 33: .Where(kvp => kvp.Value.FromClient == fromClient && (kvp.Value.To == replyTo || string.IsNullOrWhiteSpace(kvp.Value.To))) 34: .FirstOrDefault(); 35: if (entity.Key != Guid.Empty && entity.Value != null) 36: { 37: _queue.TryRemove(entity.Key, out e); 38: } 39: } 40: if (e == null) 41: { 42: Thread.Sleep(100); 43: } 44: else 45: { 46: return new BusMessage(e.ID.ToString(), e.From, e.To, e.Content); 47: } 48: } 49: } 50:  51: public void Dispose() 52: { 53: } 54: } The InProcMessageBus stores the messages in the objects of InProcMessageEntity, which can take some extra information beside the WCF message itself. 1: public class InProcMessageEntity 2: { 3: public Guid ID { get; set; } 4: public string Content { get; set; } 5: public bool FromClient { get; set; } 6: public string From { get; set; } 7: public string To { get; set; } 8:  9: public InProcMessageEntity() 10: : this(string.Empty, false, string.Empty, string.Empty) 11: { 12: } 13:  14: public InProcMessageEntity(string content, bool fromClient, string from, string to) 15: { 16: ID = Guid.NewGuid(); 17: Content = content; 18: FromClient = fromClient; 19: From = from; 20: To = to; 21: } 22: }   Summary OK, now I have all necessary stuff ready. The next step would be implementing our WCF message bus transport extension. In this post I described two scaling-out approaches on the service side especially if we are using the cloud platform: dispatcher mode and pulling mode. And I compared the Pros and Cons of them. Then I introduced the WCF channel stack, channel mode and the transport extension part, and identified what we should do to create our own WCF transport extension, to let our WCF services using pulling mode based on a message bus. And finally I provided some classes that need to be used in the future posts that working against an in process memory message bus, for the demonstration purpose only. In the next post I will begin to implement the transport extension step by step.   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

  • Problem to match font size to the screen resolution in libgdx

    - by Iñaki Bedoya
    I'm having problems to show text on my game at same size on different screens, and I did a simple test. This test consists to show a text fitting at the screen, I want the text has the same size independently from the screen and from DPI. I've found this and this answer that I think should solve my problem but don't. In desktop the size is ok, but in my phone is too big. This is the result on my Nexus 4: (768x1280, 2.0 density) And this is the result on my MacBook: (480x800, 0.6875 density) I'm using the Open Sans Condensed (link to google fonts) As you can see on desktop looks good, but on the phone is so big. Here the code of my test: public class TextTest extends ApplicationAdapter { private static final String TAG = TextTest.class.getName(); private static final String TEXT = "Tap the screen to start"; private OrthographicCamera camera; private Viewport viewport; private SpriteBatch batch; private BitmapFont font; @Override public void create () { Gdx.app.log(TAG, "Screen size: "+Gdx.graphics.getWidth()+"x"+Gdx.graphics.getHeight()); Gdx.app.log(TAG, "Density: "+Gdx.graphics.getDensity()); camera = new OrthographicCamera(); viewport = new ExtendViewport(Gdx.graphics.getWidth(), Gdx.graphics.getWidth(), camera); batch = new SpriteBatch(); FreeTypeFontGenerator generator = new FreeTypeFontGenerator(Gdx.files.internal("fonts/OpenSans-CondLight.ttf")); font = createFont(generator, 64); generator.dispose(); } private BitmapFont createFont(FreeTypeFontGenerator generator, float dp) { FreeTypeFontGenerator.FreeTypeFontParameter parameter = new FreeTypeFontGenerator.FreeTypeFontParameter(); int fontSize = (int)(dp * Gdx.graphics.getDensity()); parameter.size = fontSize; Gdx.app.log(TAG, "Font size: "+fontSize+"px"); return generator.generateFont(parameter); } @Override public void render () { Gdx.gl.glClearColor(1, 1, 1, 1); Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT); int w = -(int)(font.getBounds(TEXT).width / 2); batch.setProjectionMatrix(camera.combined); batch.begin(); font.setColor(Color.BLACK); font.draw(batch, TEXT, w, 0); batch.end(); } @Override public void resize(int width, int height) { viewport.update(width, height); } @Override public void dispose() { font.dispose(); batch.dispose(); } } I'm trying to find a neat way to fix this. What I'm doing wrong? is the camera? the viewport? UPDATE: What I want is to keep the same margins in proportion, independently of the screen size or resolution. This image illustrates what I mean.

    Read the article

  • SQL Server 2008 R2 Released (RTM)

    - by Aamir Hasan
    Microsoft announced the release of SQL Server 2008 R2 (Release to manufacturing) on (21st April 2010). See the official announcement here. The key enhancements Microsoft emphasized in the release note are: Managed self-service business intelligence (BI) for reporting and analysisEnterprise-class scalability and greater IT efficiencyPlatform integration spanning the data center to the cloud How to Get Started Download a try SQL Server R2 from the official download page.

    Read the article

  • Authenticating clients in the new WCF Http stack

    - by cibrax
    About this time last year, I wrote a couple of posts about how to use the “Interceptors” from the REST starker kit for implementing several authentication mechanisms like “SAML”, “Basic Authentication” or “OAuth” in the WCF Web programming model. The things have changed a lot since then, and Glenn finally put on our hands a new version of the Web programming model that deserves some attention and I believe will help us a lot to build more Http oriented services in the .NET stack. What you can get today from wcf.codeplex.com is a preview with some cool features like Http Processors (which I already discussed here), a new and improved version of the HttpClient library, Dependency injection and better TDD support among others. However, the framework still does not support an standard way of doing client authentication on the services (This is something planned for the upcoming releases I believe). For that reason, moving the existing authentication interceptors to this new programming model was one of the things I did in the last few days. In order to make authentication simple and easy to extend,  I first came up with a model based on what I called “Authentication Interceptors”. An authentication interceptor maps to an existing Http authentication mechanism and implements the following interface, public interface IAuthenticationInterceptor{ string Scheme { get; } bool DoAuthentication(HttpRequestMessage request, HttpResponseMessage response, out IPrincipal principal);} An authentication interceptors basically needs to returns the http authentication schema that implements in the property “Scheme”, and implements the authentication mechanism in the method “DoAuthentication”. As you can see, this last method “DoAuthentication” only relies on the HttpRequestMessage and HttpResponseMessage classes, making the testing of this interceptor very simple (There is no need to do some black magic with the WCF context or messages). After this, I implemented a couple of interceptors for supporting basic authentication and brokered authentication with SAML (using WIF) in my services. The following code illustrates how the basic authentication interceptors looks like. public class BasicAuthenticationInterceptor : IAuthenticationInterceptor{ Func<UsernameAndPassword, bool> userValidation; string realm;  public BasicAuthenticationInterceptor(Func<UsernameAndPassword, bool> userValidation, string realm) { if (userValidation == null) throw new ArgumentNullException("userValidation");  if (string.IsNullOrEmpty(realm)) throw new ArgumentNullException("realm");  this.userValidation = userValidation; this.realm = realm; }  public string Scheme { get { return "Basic"; } }  public bool DoAuthentication(HttpRequestMessage request, HttpResponseMessage response, out IPrincipal principal) { string[] credentials = ExtractCredentials(request); if (credentials.Length == 0 || !AuthenticateUser(credentials[0], credentials[1])) { response.StatusCode = HttpStatusCode.Unauthorized; response.Content = new StringContent("Access denied"); response.Headers.WwwAuthenticate.Add(new AuthenticationHeaderValue("Basic", "realm=" + this.realm));  principal = null;  return false; } else { principal = new GenericPrincipal(new GenericIdentity(credentials[0]), new string[] {});  return true; } }  private string[] ExtractCredentials(HttpRequestMessage request) { if (request.Headers.Authorization != null && request.Headers.Authorization.Scheme.StartsWith("Basic")) { string encodedUserPass = request.Headers.Authorization.Parameter.Trim();  Encoding encoding = Encoding.GetEncoding("iso-8859-1"); string userPass = encoding.GetString(Convert.FromBase64String(encodedUserPass)); int separator = userPass.IndexOf(':');  string[] credentials = new string[2]; credentials[0] = userPass.Substring(0, separator); credentials[1] = userPass.Substring(separator + 1);  return credentials; }  return new string[] { }; }  private bool AuthenticateUser(string username, string password) { var usernameAndPassword = new UsernameAndPassword { Username = username, Password = password };  if (this.userValidation(usernameAndPassword)) { return true; }  return false; }} This interceptor receives in the constructor a callback in the form of a Func delegate for authenticating the user and the “realm”, which is required as part of the implementation. The rest is a general implementation of the basic authentication mechanism using standard http request and response messages. I also implemented another interceptor for authenticating a SAML token with WIF. public class SamlAuthenticationInterceptor : IAuthenticationInterceptor{ SecurityTokenHandlerCollection handlers = null;  public SamlAuthenticationInterceptor(SecurityTokenHandlerCollection handlers) { if (handlers == null) throw new ArgumentNullException("handlers");  this.handlers = handlers; }  public string Scheme { get { return "saml"; } }  public bool DoAuthentication(HttpRequestMessage request, HttpResponseMessage response, out IPrincipal principal) { SecurityToken token = ExtractCredentials(request);  if (token != null) { ClaimsIdentityCollection claims = handlers.ValidateToken(token);  principal = new ClaimsPrincipal(claims);  return true; } else { response.StatusCode = HttpStatusCode.Unauthorized; response.Content = new StringContent("Access denied");  principal = null;  return false; } }  private SecurityToken ExtractCredentials(HttpRequestMessage request) { if (request.Headers.Authorization != null && request.Headers.Authorization.Scheme == "saml") { XmlTextReader xmlReader = new XmlTextReader(new StringReader(request.Headers.Authorization.Parameter));  var col = SecurityTokenHandlerCollection.CreateDefaultSecurityTokenHandlerCollection(); SecurityToken token = col.ReadToken(xmlReader);  return token; }  return null; }}This implementation receives a “SecurityTokenHandlerCollection” instance as part of the constructor. This class is part of WIF, and basically represents a collection of token managers to know how to handle specific xml authentication tokens (SAML is one of them). I also created a set of extension methods for injecting these interceptors as part of a service route when the service is initialized. var basicAuthentication = new BasicAuthenticationInterceptor((u) => true, "ContactManager");var samlAuthentication = new SamlAuthenticationInterceptor(serviceConfiguration.SecurityTokenHandlers); // use MEF for providing instancesvar catalog = new AssemblyCatalog(typeof(Global).Assembly);var container = new CompositionContainer(catalog);var configuration = new ContactManagerConfiguration(container); RouteTable.Routes.AddServiceRoute<ContactResource>("contact", configuration, basicAuthentication, samlAuthentication);RouteTable.Routes.AddServiceRoute<ContactsResource>("contacts", configuration, basicAuthentication, samlAuthentication); In the code above, I am injecting the basic authentication and saml authentication interceptors in the “contact” and “contacts” resource implementations that come as samples in the code preview. I will use another post to discuss more in detail how the brokered authentication with SAML model works with this new WCF Http bits. The code is available to download in this location.

    Read the article

  • Apple IIGS emulator?

    - by xiaohouzi79
    What is the best quality Apple IIGS emulator for Ubuntu that is relatively easy to install? I have tried KEGS, but get the following (working without probs on my Windows partition): Preparing X Windows graphics system Visual 0 id: 00000021, screen: 0, depth: 24, class: 4 red: 00ff0000, green: 0000ff00, blue: 000000ff cmap size: 256, bits_per_rgb: 8 Chose visual: 0, max_colors: -1 Will use shared memory for X pipes: pipe_fd = 4, 5 pipe2_fd: 6,7 open /dev/dsp failed, ret: -1, errno:2 parent dying, could not get sample rate from child ret: 0, fd: 6 errno:11

    Read the article

  • What I like about WIF&rsquo;s Claims-based Authorization

    - by Your DisplayName here!
    In “traditional” .NET with its IPrincipal interface and IsInRole method, developers were encouraged to write code like this: public void AddCustomer(Customer customer) {     if (Thread.CurrentPrincipal.IsInRole("Sales"))     {         // add customer     } } In code reviews I’ve seen tons of code like this. What I don’t like about this is, that two concerns in your application get tightly coupled: business and security logic. But what happens when the security requirements change – and they will (e.g. members of the sales role and some other people from different roles need to create customers)? Well – since your security logic is sprinkled across your project you need to change the security checks in all relevant places (and make sure you don’t forget one) and you need to re-test, re-stage and re-deploy the complete app. This is clearly not what we want. WIF’s claims-based authorization encourages developers to separate business code and authorization policy evaluation. This is a good thing. So the same security check with WIF’s out-of-the box APIs would look like this: public void AddCustomer(Customer customer) {     try     {         ClaimsPrincipalPermission.CheckAccess("Customer", "Add");           // add customer     }     catch (SecurityException ex)     {         // access denied     } } You notice the fundamental difference? The security check only describes what the code is doing (represented by a resource/action pair) – and does not state who is allowed to invoke the code. As I mentioned earlier – the who is most probably changing over time – the what most probably not. The call to ClaimsPrincipalPermission hands off to another class called the ClaimsAuthorizationManager. This class handles the evaluation of your security policy and is ideally in a separate assembly to allow updating the security logic independently from the application logic (and vice versa). The claims authorization manager features a method called CheckAccess that retrieves three values (wrapped inside an AuthorizationContext instance) – action (“add”), resource (“customer”) and the principal (including its claims) in question. CheckAccess then evaluates those three values and returns true/false. I really like the separation of concerns part here. Unfortunately there is not much support from Microsoft beyond that point. And without further tooling and abstractions the CheckAccess method quickly becomes *very* complex. But still I think that is the way to go. In the next post I will tell you what I don’t like about it (and how to fix it).

    Read the article

  • How-to tell the ViewCriteria a user chose in an af:query component

    - by frank.nimphius
    Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The af:query component defines a search form for application users to enter search conditions for a selected View Criteria. A View Criteria is a named where clauses that you can create declaratively on the ADF Business Component View Object. A default View Criteria that allows users to search in all attributes exists by default and exposed in the Data Controls panel. To create an ADF Faces search form, expand the View Object node that contains the View Criteria definition in the Data Controls panel. Drag the View Criteria that should be displayed as the default criteria onto the page and choose Query in the opened context menu. One of the options within the Query option is to create an ADF Query Panel with Table, which displays the result set in a table view, which can have additional column filters defined. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} To intercept the user query for modification, or just to know about the selected View Criteria, you override the QueryListener property on the af:query component of the af:table component. Overriding the QueryListener on the table makes sense if the table allows users to further filter the result set using column filters.To override the default QueryListener, copy the existing string referencing the binding layer to the clipboard and then select Edit from the field context menu (press the arrow icon to open it) to selecte or create a new managed bean and method to handle the query event.  The code below is from a managed bean with custom query listener handlers defined for the af:query component and the af:table component. The default listener entry copied to the clipboard was "#{bindings.ImplicitViewCriteriaQuery.processQuery}"  public void onQueryList(QueryEvent queryEvent) {   // The generated QueryListener replaced by this method   //#{bindings.ImplicitViewCriteriaQuery.processQuery}        QueryDescriptor qdes = queryEvent.getDescriptor();          //print or log selected View Criteria   System.out.println("NAME "+qdes.getName());           //call default Query Event        invokeQueryEventMethodExpression("      #{bindings.ImplicitViewCriteriaQuery.processQuery}",queryEvent);  } public void onQueryTable(QueryEvent queryEvent) {   // The generated QueryListener replaced by this method   //#{bindings.ImplicitViewCriteriaQuery.processQuery}   QueryDescriptor qdes = queryEvent.getDescriptor();   //print or log selected View Criteria   System.out.println("NAME "+qdes.getName());                   invokeQueryEventMethodExpression(     "#{bindings.ImplicitViewCriteriaQuery.processQuery}",queryEvent); } private void invokeQueryEventMethodExpression(                        String expression, QueryEvent queryEvent){   FacesContext fctx = FacesContext.getCurrentInstance();   ELContext elctx = fctx.getELContext();   ExpressionFactory efactory   fctx.getApplication().getExpressionFactory();     MethodExpression me =     efactory.createMethodExpression(elctx,expression,                                     Object.class,                                     new Class[]{QueryEvent.class});     me.invoke(elctx, new Object[]{queryEvent}); } Of course, this code also can be used as a starting point for other query manipulations and also works with saved custom criterias. To read more about the af:query component, see: http://download.oracle.com/docs/cd/E15523_01/apirefs.1111/e12419/tagdoc/af_query.html

    Read the article

< Previous Page | 849 850 851 852 853 854 855 856 857 858 859 860  | Next Page >