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: mhT3 Fwc
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CountBean.java .P-@ !Q5*
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/* ix*n<lCoC
* CountData.java M nH4p
* R9fM9
* Created on 2007年1月1日, 下午4:44 a|lcOU
* 0alm/or
* To change this template, choose Tools | Options and locate the template under n uhKM.a{
* the Source Creation and Management node. Right-click the template and choose ]NG`MZ
* Open. You can then make changes to the template in the Source Editor.
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*/ *,@dt+H!y
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package com.tot.count; A$[@AY$MI
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/** Z?CmD;W
* ?uOdqMJV
* @author |u7vY/
*/ ~.yt
public class CountBean { G W|~sE +
private String countType; #R'm|En'
int countId; b2r@vZ]D
/** Creates a new instance of CountData */ L%U-MOS=
public CountBean() {} zF3fpEKe
public void setCountType(String countTypes){ j01#Wq_\fk
this.countType=countTypes; 1[:?oEI
} jrZM
public void setCountId(int countIds){ -:AknQq
this.countId=countIds; .)ZK42Qd
} Et4gRS)\
public String getCountType(){ kd9hz-*
return countType; \h,S1KmIBD
} Mw*R~OX
public int getCountId(){ x.xfMM2n
return countId; &v'e;W
} mJ)o-BV
} q.g<g u]
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CountCache.java `N]!-=o
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/* VAGQR&T?
* CountCache.java C|or2
* Q:rQ;/b0/
* Created on 2007年1月1日, 下午5:01 FR5P;Yz%H
* YC,)t71l{
* To change this template, choose Tools | Options and locate the template under QV&yVH=Xs
* the Source Creation and Management node. Right-click the template and choose b"J J3$D
* Open. You can then make changes to the template in the Source Editor. "CH3\O\
*/ VDnN2)Km*
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package com.tot.count; ()cqax4
import java.util.*; Dej_(Dz_S
/** ?q lpi(
* _/\U
* @author kuX{2h*`
*/ 655OL)|cD6
public class CountCache { 8*$HS.Db'
public static LinkedList list=new LinkedList(); m,3H]
/** Creates a new instance of CountCache */ RkMs!M
public CountCache() {} <meQ
public static void add(CountBean cb){ LtK= nK
if(cb!=null){
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list.add(cb); CW+] Jv]"
} 9|{t%F=-
} ;Yr?"|
} .,l4pA9v
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CountControl.java 8aMmz!S
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/* :={rPj-nU
* CountThread.java
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* ai$s
* Created on 2007年1月1日, 下午4:57 vo!QJ
* dhCrcYn
* To change this template, choose Tools | Options and locate the template under VC.zmCglo^
* the Source Creation and Management node. Right-click the template and choose E06)&tF
* Open. You can then make changes to the template in the Source Editor. ["~T)d'
*/ Lz:Q6
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package com.tot.count; -Crm#Ib~
import tot.db.DBUtils; r=Od%
import java.sql.*; n>L24rL
/** r3mmi5
* txFcV
* @author SS7C|*-Zd
*/ j*L-sU
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 4cZlQ3OE.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,nGZ(EBD
/** Creates a new instance of CountThread */
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public CountControl() {} ey ?paT
public synchronized void executeUpdate(){ LR%P\~
Connection conn=null; t`G<}t
PreparedStatement ps=null; :~LOw}N!aQ
try{ }cd-BW
conn = DBUtils.getConnection(); NUM+tg>KM
conn.setAutoCommit(false); 6bd{3@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GEZ!z5";BQ
for(int i=0;i<CountCache.list.size();i++){ {9|S,<9
CountBean cb=(CountBean)CountCache.list.getFirst(); jFGY`9Zw0
CountCache.list.removeFirst(); XBN,{
ps.setInt(1, cb.getCountId()); R/ 3#(5
ps.executeUpdate();⑴ ^#&PTq>
//ps.addBatch();⑵ n$E'+kox
} q|S,^0cU
//int [] counts = ps.executeBatch();⑶ L]3gHq
conn.commit(); Gn>~CoFN
}catch(Exception e){ ~vstuRRST
e.printStackTrace(); Ep8 y
} finally{ g7O,
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try{ *(j-jbA
if(ps!=null) { ?Y'r=Q{w
ps.clearParameters(); e*hCf5=-
ps.close(); Rkh
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ps=null; P/ 7aj:h~P
} +YnQOh%v0s
}catch(SQLException e){} % QI6`@Y"
DBUtils.closeConnection(conn); #}aBRKZf6
} }(v <f*7=n
} oxJ#NGD
public long getLast(){ 4 ky/a1y-
return lastExecuteTime; QIu!o,B
} \!!1o+#1j
public void run(){ Vho^a:Z9}W
long now = System.currentTimeMillis(); Ops""#Zi
if ((now - lastExecuteTime) > executeSep) { Su/}OS\R
//System.out.print("lastExecuteTime:"+lastExecuteTime); 15wwu} X
//System.out.print(" now:"+now+"\n"); ~PiCA
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); O*-sSf
lastExecuteTime=now; vC _O!2E
executeUpdate(); u,),kj<
} n8 e4`-cY
else{ b@yFqgJ_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} rKr2 K'
} O>sE~~g]?
} MD=VR(P?eq
//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 oLz9mqp2%
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类写好了,下面是在JSP中如下调用。 d&5GkD.P
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<% )0xEI
CountBean cb=new CountBean(); /7-qb^V
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `8N],X
CountCache.add(cb); o;M-M(EZQ6
out.print(CountCache.list.size()+"<br>"); wO3K2I]>0
CountControl c=new CountControl(); 7z4u?>pne*
c.run(); I0]"o#LjT
out.print(CountCache.list.size()+"<br>"); L}5IX)#gH
%>