有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: BQH}6ueZ
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CountBean.java $j}OB6^I
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/* WYB{% yf
* CountData.java =Z=o#46JY
* Ian[LbCWB
* Created on 2007年1月1日, 下午4:44 1NQbl+w#I
* CIU1R;
* To change this template, choose Tools | Options and locate the template under G;NF5`*4mc
* the Source Creation and Management node. Right-click the template and choose GeszgtK{T
* Open. You can then make changes to the template in the Source Editor. NA3\
*/ X$%4$
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package com.tot.count; 0:0NXVYs&
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/** 'r1LSht'
* g_5Q A)4x
* @author e:H26 SW
*/ DejA4XdW
public class CountBean { Twn4lG4~
private String countType; 7dsefNPb
int countId; H ]4Hj
/** Creates a new instance of CountData */ 76hOB@
public CountBean() {} }Sy=My89r
public void setCountType(String countTypes){ xGTP;NT_H
this.countType=countTypes; !EUan
} u:0aM}9A
public void setCountId(int countIds){ -*5Rnx|Y{
this.countId=countIds; f&v9Q97=
} ]smkTo/
public String getCountType(){ AJ#Nenmj
return countType; 2 41*!
} {uzf"%VtP
public int getCountId(){ __mF?m
return countId; p<=$&*
} PkI:*\R
} quY:pqG38q
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CountCache.java F:x [
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/* H":oNpfb
* CountCache.java
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* ;b-XWK=
* Created on 2007年1月1日, 下午5:01 MEB it
* B)d(TP,>
* To change this template, choose Tools | Options and locate the template under I`NjqyTW
* the Source Creation and Management node. Right-click the template and choose <&C]sb
* Open. You can then make changes to the template in the Source Editor. )1X#*mCxk
*/ &b:1I7Cp*
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package com.tot.count; !47n[Zs
import java.util.*; 1GzAG;UUo6
/** t.mVO]dsj
* (o`{uj{!
* @author Hh+ 2mkg
*/ F'0O2KQ
public class CountCache { dAuJXGo
public static LinkedList list=new LinkedList(); Kr)a2rZ}SL
/** Creates a new instance of CountCache */ K6R.@BMN
public CountCache() {} gEjdN.
public static void add(CountBean cb){ P&f7@MOV.P
if(cb!=null){ 'inFKy'H
list.add(cb); % >=!p
} M3.do^ss
} <Y}R#o1Z
} } }59V&'t
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CountControl.java WPQ fhr#|
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/* $&=S#_HQS
* CountThread.java 0)gdB'9V_
*
$ ` ""
* Created on 2007年1月1日, 下午4:57 jnn}V~L
* %KLpig
* To change this template, choose Tools | Options and locate the template under }~L.qG
* the Source Creation and Management node. Right-click the template and choose :=Nz}mUV
* Open. You can then make changes to the template in the Source Editor. j:v@pzTD
*/ K|epPGRr
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package com.tot.count; .6Pw|xu`Pw
import tot.db.DBUtils; $&n=$C&x
import java.sql.*; I`!<9OTBj
/** Vh4X%b$TV
* -Ps!LI{@
* @author )?anOD[
*/ vQ
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public class CountControl{ tVN
private static long lastExecuteTime=0;//上次更新时间 ]Gsv0Xk1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3ca (i/c
/** Creates a new instance of CountThread */ U2W|:~KM
public CountControl() {} ?82xdpg
public synchronized void executeUpdate(){ Tw-;7Ae
Connection conn=null; 9dx/hFA
PreparedStatement ps=null; + R~'7*EI
try{ bKMy|_
conn = DBUtils.getConnection(); W:pIPDx1=!
conn.setAutoCommit(false); e w$B)W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]>5/PD,wWy
for(int i=0;i<CountCache.list.size();i++){ a.k.n<
CountBean cb=(CountBean)CountCache.list.getFirst(); &i6),{QN
CountCache.list.removeFirst(); rX2.i7i,
ps.setInt(1, cb.getCountId()); 9sYMSc~Bm
ps.executeUpdate();⑴ wfLaRP
//ps.addBatch();⑵ #Lh;CSS
} [1Qo#w1
//int [] counts = ps.executeBatch();⑶ p8Qk'F=h
conn.commit(); !Wntd\w
}catch(Exception e){ I 5^!y
e.printStackTrace(); rlOAo`hd
} finally{ ;DfY#-
try{ g}1B;zGf
if(ps!=null) { vN;N/mL
ps.clearParameters(); LTQ"8
ps.close(); <L8'! q}
ps=null; ,/Z%@-rF
} K0|FY=#2y
}catch(SQLException e){} TrEu'yxy8*
DBUtils.closeConnection(conn); 3u+T~g0^
} f<d`B]$(
} ?BeiY zg
public long getLast(){ 7x|9n
return lastExecuteTime; $r@zs'N
} iL-(O;n
public void run(){ -b9\=U[
long now = System.currentTimeMillis(); yg<R=$n,Q
if ((now - lastExecuteTime) > executeSep) { "^})zf~_
//System.out.print("lastExecuteTime:"+lastExecuteTime); ) j#`r/
//System.out.print(" now:"+now+"\n"); Rq'S>#e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3Ei#q+7
lastExecuteTime=now; gwuI-d^
executeUpdate(); XpB_N{v9w
} Q4#m\KK;i9
else{ y}" O U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M=@:ZQ^!
} K7_UP&`=J
} 'T*&'RQr
} &
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 >
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类写好了,下面是在JSP中如下调用。 AUG#_HE]k
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<% _Eo[7V{NY
CountBean cb=new CountBean(); cJ=6r
:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cKca;SNql1
CountCache.add(cb); !Iy_UfW
out.print(CountCache.list.size()+"<br>"); *SJ_z(CZm
CountControl c=new CountControl(); EU/C@B2*Dl
c.run(); NZ:,ph
out.print(CountCache.list.size()+"<br>"); @1roe
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