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: &fB=&jc*j
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CountBean.java ~B{08%|oK
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/* 2Jt{oh |
* CountData.java ;l!<A
* 3H!]X M
* Created on 2007年1月1日, 下午4:44 V$hL\`e
* CsZm8oL$
* To change this template, choose Tools | Options and locate the template under Mbxl{M
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* the Source Creation and Management node. Right-click the template and choose fCUx93,>z
* Open. You can then make changes to the template in the Source Editor. 15jQ87)
*/ S'HA]
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package com.tot.count; `l]Lvk8O
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/** h.K"v5I*
* Ew0)MZ.#
* @author uEb:uENk'(
*/ V7U*09
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public class CountBean { yJ!26
private String countType; &UH0Tw4
int countId; 'sIne>
/** Creates a new instance of CountData */ 8WV5'cX
public CountBean() {} Zo2+{a
public void setCountType(String countTypes){ >g !Z|ju
this.countType=countTypes; b/[X8w'VP
} 'sZGLgT;m
public void setCountId(int countIds){ z&H.fs L
this.countId=countIds; By6O@ .\V
} 1P"7.{
public String getCountType(){ j>8ubA
return countType; 2
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} (km
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public int getCountId(){ 424iFc[
return countId; I<RARB-j
} ]CNPy$>*
} bxYSZCo*
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CountCache.java U<&=pv
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/* 4RDY_HgF6
* CountCache.java uT=r*p(v
* S8AbLl9G@>
* Created on 2007年1月1日, 下午5:01 TP#Ncqh
* Io<T'K
* To change this template, choose Tools | Options and locate the template under bp'%UgA)1
* the Source Creation and Management node. Right-click the template and choose =KQIrS:
* Open. You can then make changes to the template in the Source Editor. SM)"vr_
*/ 69$R.
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package com.tot.count; 1/mBp+D
import java.util.*; $s=` {v v
/** h{7>>
* XE_Lz2H`
* @author EXeV@kg
*/ yg8= G vO
public class CountCache { Xbmsq,*]
public static LinkedList list=new LinkedList(); M{orw;1Isy
/** Creates a new instance of CountCache */
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public CountCache() {} j xI;clr
public static void add(CountBean cb){ rNhS\1-
if(cb!=null){ rF[-4t
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list.add(cb); c*\i%I#f2
} sHPAr}14
} GmNCw5F
} >x%HqP#_V
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CountControl.java {i=V:$_#
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/* #f(tzPD
* CountThread.java T\Xf0|y
* 8Ys)q x>7'
* Created on 2007年1月1日, 下午4:57 }.D18bE(
* >|RoLV
* To change this template, choose Tools | Options and locate the template under "Ai\NC
* the Source Creation and Management node. Right-click the template and choose &V
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* Open. You can then make changes to the template in the Source Editor. \YJQN3^46>
*/ vbJdhaf
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package com.tot.count; %`pi*/(
import tot.db.DBUtils; ^!
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import java.sql.*; Kn$t_7AF^
/** ?`Z:vqp>Z
* *>?N>f"
* @author 4P?`<K'
*/ ncadVheKt
public class CountControl{ 6?5dGYAX<
private static long lastExecuteTime=0;//上次更新时间 !L;_f'\)6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 vG6*[c8
/** Creates a new instance of CountThread */ lFf>z}eLy
public CountControl() {} A-B>VX
public synchronized void executeUpdate(){ Ln6emXqw
Connection conn=null; "
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PreparedStatement ps=null; 0x5\{f
try{ <WWZb\"{
conn = DBUtils.getConnection(); 4/{pz$
conn.setAutoCommit(false); OH`zeI,[*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VFawASwQ
for(int i=0;i<CountCache.list.size();i++){ S=S/]]e
CountBean cb=(CountBean)CountCache.list.getFirst(); !W,LG$=/
CountCache.list.removeFirst(); 2V;{@k
ps.setInt(1, cb.getCountId()); %w>3Fwj`z
ps.executeUpdate();⑴ Iu0GOy*[
//ps.addBatch();⑵ Zc38ht\r;
} G"3KYBN>
//int [] counts = ps.executeBatch();⑶ \nyqW4nTm
conn.commit(); 2sgp$r
}catch(Exception e){ lAG@nh^
e.printStackTrace(); zk3\v
"
} finally{ 28M^F~0
try{ 4 5wqX h
if(ps!=null) { _~tF2`,Y_p
ps.clearParameters(); Ha]vG@?+
ps.close(); 416}# Mk
ps=null; wbr$w>n
} Rf)|p;
}catch(SQLException e){} 5`&@3
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DBUtils.closeConnection(conn); f'"PQr^9
} /T {R\
} ;2`t0#J$]
public long getLast(){ W\0u[IV.x
return lastExecuteTime; 6yUThv.G#
} %j@/Tx/
public void run(){ Y5ei:r|^
long now = System.currentTimeMillis(); cGo_qR/B(>
if ((now - lastExecuteTime) > executeSep) { 0FL'8!e<
//System.out.print("lastExecuteTime:"+lastExecuteTime); n|T$3j)
//System.out.print(" now:"+now+"\n"); yYe>a^r4R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); y+$vHnS/jC
lastExecuteTime=now; d14@G4#Bd
executeUpdate(); )@U~Li/+
} HLthVc w
else{ /g%RIzgW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _7u&.l<;
} E}%Pwr
} 5cM%PYU4:v
} R)N^j'R~=
//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 +-TEB
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类写好了,下面是在JSP中如下调用。 %*<Wf4P"
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<% "WmsBdO
CountBean cb=new CountBean(); '-~J.8-</
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); w AdaP9h
CountCache.add(cb); Z= -fL
out.print(CountCache.list.size()+"<br>"); p|qLr9\A
CountControl c=new CountControl(); OU/3U(%n]e
c.run(); ]X7_ji(l,
out.print(CountCache.list.size()+"<br>"); .i?{h/9y
%>