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: t2#zQ[~X!
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CountBean.java 8e}8@[h
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/* ah|`),o(k
* CountData.java ~_W>ND
* Ops""#Zi
* Created on 2007年1月1日, 下午4:44 ?J's>q^X
* .q_SA-!w>
* To change this template, choose Tools | Options and locate the template under >&l{_b\k
* the Source Creation and Management node. Right-click the template and choose T[]kun
* Open. You can then make changes to the template in the Source Editor. -`d(>ok
*/ A:YWXcg
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package com.tot.count; <G#z;]N
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/** *tL1t\jY
* Ps9YP B-
* @author tqT-9sEXX.
*/ IXt cHAgX
public class CountBean { FN29 5:Iuw
private String countType; 9Li.B1j
int countId; MRL,#+VxA
/** Creates a new instance of CountData */ dX;G[\
public CountBean() {} [Se0+\,&
public void setCountType(String countTypes){ Z=CY6Zu7
this.countType=countTypes; V'XvwO@
} BRGTCR
public void setCountId(int countIds){ ~AG."<}
this.countId=countIds; ~[9(}UM
} X]AbBzy
public String getCountType(){ uq_h8JH$
return countType; SWM6+i
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} ~L=Idt!9
public int getCountId(){ XqK\'8]\Mw
return countId; N~@VZbS(6
} P
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} 1$adX
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CountCache.java 1q(o3%
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/* .3*VkAs
* CountCache.java UONW3}-
* bLpGrGJs
* Created on 2007年1月1日, 下午5:01 yyVv@
* t(F] -[
* To change this template, choose Tools | Options and locate the template under #3o]Qo[Sc
* the Source Creation and Management node. Right-click the template and choose A`qb5LLJ)
* Open. You can then make changes to the template in the Source Editor. Nd.Tda!Kg
*/
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package com.tot.count; smt6).o
import java.util.*; W9ewj:4\0
/** >J[Wd<~t
* $S0eERga
* @author 1*Ui=M4
*/ N}2xt)JZz
public class CountCache { )wwQv2E
public static LinkedList list=new LinkedList(); [F<Tl =
/** Creates a new instance of CountCache */ wf8GH}2A
public CountCache() {} y~N,=5>j
public static void add(CountBean cb){ StuDtY
if(cb!=null){ ,lly=OhKb
list.add(cb); [ZP8[Zl'?
} n/3gx4.g
} De*Z UN|<
} boR&'yX
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CountControl.java (]mh}=:KDg
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/* Q(2X$7iRq
* CountThread.java 2S\~
* n_n0Q}du
* Created on 2007年1月1日, 下午4:57 0Up@+R2
* b:}`O!UBw
* To change this template, choose Tools | Options and locate the template under ReCmv/AE
* the Source Creation and Management node. Right-click the template and choose LyB$~wZx~@
* Open. You can then make changes to the template in the Source Editor. t?0D* !D
*/ PIuk]&L^
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package com.tot.count; A2b
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import tot.db.DBUtils; ,Jf)A/_
import java.sql.*; _F *("
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/** nNIV(
* O\T
* @author X"W%(x`w
*/ 26E"Ui5q
public class CountControl{ |*N.SS
private static long lastExecuteTime=0;//上次更新时间 %3i/PIN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zJ#e3o .
/** Creates a new instance of CountThread */ WG;1[o&
public CountControl() {} Tv0|e'^
public synchronized void executeUpdate(){ <4y1[/S
Connection conn=null; <=V2~
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PreparedStatement ps=null; qB_MDA
try{ ^)b*"o
conn = DBUtils.getConnection(); q0
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conn.setAutoCommit(false); S zOB{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qoMYiF}/e
for(int i=0;i<CountCache.list.size();i++){ Ou;
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CountBean cb=(CountBean)CountCache.list.getFirst(); Etj*3/n|
CountCache.list.removeFirst(); xyx.1o
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ps.setInt(1, cb.getCountId()); M%:ACLYP
ps.executeUpdate();⑴ aT F}
//ps.addBatch();⑵ +7o3TA]-
} ,SJB3if
//int [] counts = ps.executeBatch();⑶ ;0}$zy1EZ
conn.commit(); GD|uU
}catch(Exception e){ w&v_#\T
e.printStackTrace(); mqk~Pno|<
} finally{ r]km1SrS
try{ ?N#mD
if(ps!=null) { Rcf_31 L
ps.clearParameters(); KS'? DO
ps.close(); &:8a[C2=
ps=null; =4yME
} #HB]qa
}catch(SQLException e){} Iq_cs
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DBUtils.closeConnection(conn); FgRlxz
} Y{@ez
} HPpKti7g
public long getLast(){ Qm,|'y:Tg
return lastExecuteTime; Gy
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} g`gH]W
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public void run(){ +"T?.,
long now = System.currentTimeMillis(); zp"sM
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if ((now - lastExecuteTime) > executeSep) { ]m(Uv8/6
//System.out.print("lastExecuteTime:"+lastExecuteTime); a)4.[+wnRf
//System.out.print(" now:"+now+"\n"); zF(I#|Vo
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (C,PGjd
lastExecuteTime=now; kwZ8q-0
executeUpdate(); vgHMVzxj
} >mT2g
else{ KCDEMs}}zM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); qJVW :$1q
} 'wLQ9o%=p|
} .!,T>:R
}
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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 A"#Gg7]tl'
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类写好了,下面是在JSP中如下调用。 JpxJZJ
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<% me$7\B;wy
CountBean cb=new CountBean(); 5X nA.?F^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); x g/3*rL
CountCache.add(cb); X|7gj&1
out.print(CountCache.list.size()+"<br>"); ]k]P (w
CountControl c=new CountControl(); ,F.\ z^\{
c.run(); yiSv#wD9
out.print(CountCache.list.size()+"<br>"); eL#pS=
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