Atitit. The stability of the upgrade software---persistent cyclic queue based on database implementation

Atitit. stability of the upgrade software --- implementing persistent cyclic queue ring queue based on database

1. Preface :: selection ( horse ) 1

2. Implementing the java.util.queue Interface 1

3. 2 implementations of the current pointer 1

1.1. With a cursor last to indicate (the pointer table field last ), troublesome , not recommended 1

1.2. ( simple , recommended ) Use the number of cycles to indicate that each loop adds 1 ( field Cirtimes), ORDER by Cirtimes 1

4. Table Design ID, cirtimes,createtime,handlerid,recid,delflag 1

5. Circular queue Loop Queue usage Flow 2

1.3. Increase the queue Addall,add 2

1.4. Grab the element to be processed peek (int fetchcount) Delflag=0,order by Cirtimes 2

1.5. Out of the squad and append to the end of the team Remove,removeall (list)::: cirtimes++; 2

1. Preface:: Selection (horse)

Pick a Li Yiwa , a implet for the horse

In order to use the Loop queue , the stability of the queue can be greatly improved . prevent push messages outdate do not send . .. and avoid the queue to stay stuck

2. Implement the Java.util.queue interface

3.2 implementations of the current pointer

1.1. With a cursor last to indicate (the Pointer table field last), troublesome, not recommended 1.2. (simple, recommended) use the number of cycles to indicate that each loop adds 1 (field cirtimes), and order by Cirtimes

Author :: Old Wow's paw attilax ayron,email:[email protected]

Reprint please indicate source: Http://blog.csdn.net/attilax

4. Table Design ID, Cirtimes,createtime,handlerid,recid,delflag

ID, Cirtimes,createtime,handlerid,recid,delflag

Handlerid:: be able to make a lot of processor use , each processor just get their own queue .

RecId:: associated Rec ID ...

5. Circular queue loop queue using flow 1.3. Increase Queue Addall,add

1.4. Fetching the elements to be processedPeek(int Fetchcount)  Delflag=0,order by Cirtimes

Public List Peek( int fetchcount) {

//  Attilax Old Wow's paw m_9_r o7s

Final List li = new ArrayList ();

Noticeflag is null

String hql="from Gvdownloadtask where 1=1 and downloadstatus are null ORDER by NOTICEFL AG ";

Query Q = getsession(). CreateQuery (hql) ;  

Q . Setfirstresult (0) ;  

Q . Setmaxresults (fetchcount) ;  

List l = q. List ();  

return l;

}

1.5. Out of the squad and append to the end of the team Remove,removeall (list)::: cirtimes++;

T . Setnoticeflag (t. Getnoticeflag ()+1);

C . Merge (t) ;

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Atitit. The stability of the upgrade software---persistent cyclic queue based on database implementation