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: v&66F`
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CountBean.java C6tfFS3bq
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/* `RE
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* CountData.java q(#,X~0
* -3y
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* Created on 2007年1月1日, 下午4:44
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* 01%0u8U
* To change this template, choose Tools | Options and locate the template under gHWsKE
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* the Source Creation and Management node. Right-click the template and choose m{yq.H[X
* Open. You can then make changes to the template in the Source Editor. NeewV=[%
*/ W{}M${6&
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package com.tot.count; K1-3!G
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/**
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* Q'^$;X~-<
* @author $D*Yhv!/
*/ fzjtaH?
public class CountBean { 7zNfq.Ni~
private String countType; N;cSR\Ng
int countId; 9J}^{AA
/** Creates a new instance of CountData */ CT=5V@_u\
public CountBean() {} immf\
public void setCountType(String countTypes){ 8tT/w5
this.countType=countTypes; 4)snt3k
} catJC3
public void setCountId(int countIds){ p<RIvSqM
this.countId=countIds; BDi+*8
} 2d OUY
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public String getCountType(){ mP
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return countType; %LnG^L
} A{Y/eG8
public int getCountId(){ Ht~YSQ~:y
return countId; y(**F8>?xE
} xUB{{8B:L
} \%#luk@:
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CountCache.java :-+j,G9t
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/* $j0<ef!
* CountCache.java 6s:
* q:,ck@-4
* Created on 2007年1月1日, 下午5:01 |@MGGAk
* Y^5)u/Y=U
* To change this template, choose Tools | Options and locate the template under xI5zP?
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* the Source Creation and Management node. Right-click the template and choose V:8{MO(C\
* Open. You can then make changes to the template in the Source Editor. C^
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*/ ZP4y35&%y
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package com.tot.count; R+=Xr<`%U|
import java.util.*; l27J
/** %/K;!'7
* Mbxrj~ue
* @author TzV~I\a|
*/ iB{l:
public class CountCache { Vf$q3X
public static LinkedList list=new LinkedList(); "Qe2U(Un
/** Creates a new instance of CountCache */ #\O?|bN'q
public CountCache() {} 3=^B
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public static void add(CountBean cb){ v*@R U
if(cb!=null){ 6"o@d8>v
list.add(cb); ]~'pYOB
} -$f$z(h
} l`E KL2n
} n!?u/[@
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CountControl.java xcXnd"YYE
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/* ,@@FAL
* CountThread.java %uy?@ e
* SrvC34<7
* Created on 2007年1月1日, 下午4:57 ia%U;M
* n'<F'1SWv
* To change this template, choose Tools | Options and locate the template under b5UIX Kim
* the Source Creation and Management node. Right-click the template and choose g;</ |Z
* Open. You can then make changes to the template in the Source Editor. pIvr*UzY
*/ I oC}0C7
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package com.tot.count; iaQ3mk#
import tot.db.DBUtils; 2NWQiSz
import java.sql.*; R-BN}ZS
/** m)xz_Plc
* !MD uj
* @author l|
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*/ 20BU;D3
public class CountControl{ ap .L=vn
private static long lastExecuteTime=0;//上次更新时间 BGL-lJrG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \7tJ)[0aF
/** Creates a new instance of CountThread */ Jgzg[6
public CountControl() {} h1Q rFPQnu
public synchronized void executeUpdate(){ 7j{63d`2
Connection conn=null; :stA]JB#
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PreparedStatement ps=null; ]iH~1 [
try{ x@,B))WlGr
conn = DBUtils.getConnection(); :.F;LF&
conn.setAutoCommit(false); XbW 1`PH
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SQI =D8
for(int i=0;i<CountCache.list.size();i++){ {'q(a4
CountBean cb=(CountBean)CountCache.list.getFirst(); -ob1_0
CountCache.list.removeFirst(); JA6#qlylL
ps.setInt(1, cb.getCountId()); t;)`+K#1:
ps.executeUpdate();⑴ )ZDqj
//ps.addBatch();⑵ 1H7bPl|
} JcI~8;Z@Z~
//int [] counts = ps.executeBatch();⑶ Zl=IZ?F
conn.commit(); 'FmnlC1
}catch(Exception e){ xw~&OF&
e.printStackTrace(); e4Jx%v?_P
} finally{ G:!'hadw
try{ :LX
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if(ps!=null) { fTV}IP
ps.clearParameters(); ?8@EBPpC
ps.close(); q
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ps=null; IM&l%6[).
} 4j-%I7
}catch(SQLException e){} s7na!A[
DBUtils.closeConnection(conn); MDOP2y`2i
} +>o}
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} tLe"i>
public long getLast(){ ]MV=@T^8#
return lastExecuteTime; bRK[u\,
} 0z=^_Fb
public void run(){ '645Fr[lg
long now = System.currentTimeMillis(); vS+E`[
if ((now - lastExecuteTime) > executeSep) { )W$@phY(I
//System.out.print("lastExecuteTime:"+lastExecuteTime); g7<u eF
//System.out.print(" now:"+now+"\n"); #(Ezt% ^
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {&s.* 5
lastExecuteTime=now; 5SwQ9#
executeUpdate(); DeRC_ [
} dp#'~[ j
else{ Lsz)\yIPj
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Jnf@u
} n*vhCeL
} Ox}a\B8
} J={IGA
//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 SW*Yu{
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类写好了,下面是在JSP中如下调用。 {N 0i
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<% B/ACU
CountBean cb=new CountBean(); QAKA3{-(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Xmaj7*f>p
CountCache.add(cb); \tZZn~ex
out.print(CountCache.list.size()+"<br>"); ) E(9
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CountControl c=new CountControl(); WeRX ~
c.run(); #tQ__V
out.print(CountCache.list.size()+"<br>"); `{W>Dy
%>