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: sxuYwQ
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CountBean.java 0#yo\McZ
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/* @|cas|U.r
* CountData.java a]ftE\99
* Y)!5Z.K
* Created on 2007年1月1日, 下午4:44 `U;4O)`n
* Nz]\%c/-
* To change this template, choose Tools | Options and locate the template under xUeLX`73
* the Source Creation and Management node. Right-click the template and choose (>Tu~Vo
* Open. You can then make changes to the template in the Source Editor. =UYc~VUYnT
*/ ~5JXY5*o
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package com.tot.count; ,m:MI/)p
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/**
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* 7pGlbdS
* @author gx9H=c>/
*/ dwmj*+
public class CountBean { /[us;=CM
private String countType; *.i`hfRc
int countId; 4K4?Q+?
/** Creates a new instance of CountData */ QU\|RX
public CountBean() {} |#MA?oz3T
public void setCountType(String countTypes){ EmH2 Dbw
this.countType=countTypes; yCmiW
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} H(""So7L
public void setCountId(int countIds){ .=K@M"5&
this.countId=countIds; (A?e}M^}
} T$RZRZo
public String getCountType(){ u/``*=Y@
return countType; hB|LW^@v
} 5$jKw\FF=
public int getCountId(){ O@EpRg1
return countId; % +eZ U)N
} NB>fr#pb
} )TP7gLv=b
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CountCache.java A3h[VnuG,
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/* }9@,EEhg
* CountCache.java }t]CDa_n
* s K s
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* Created on 2007年1月1日, 下午5:01 )TV'eq
* QDyL0l{C
* To change this template, choose Tools | Options and locate the template under <G#JPt6
* the Source Creation and Management node. Right-click the template and choose eyUo67'7
* Open. You can then make changes to the template in the Source Editor. IF@)L>-%
*/ Rb\\6BU0
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package com.tot.count; $%sOL(
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import java.util.*; 6R#f 8
/** - x7b6o>$
* !R4`ihi1
* @author &{"aD&
*/ ;JDxl-~
public class CountCache { UX(#C,qgG
public static LinkedList list=new LinkedList(); 9r8*'.K`Z
/** Creates a new instance of CountCache */ Q7f\ 5QjT
public CountCache() {} A-4\;[P\
public static void add(CountBean cb){ q *-q5FE
if(cb!=null){ Li iQ;x
list.add(cb); q(_pk&/
} 4WDh8U
} 7X1T9'jI2
} KLlW\MF1
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CountControl.java -Vw,9VCF
,GGr@})
/* lS9rgq<n
* CountThread.java r1xNU0A
* V[Auw3)
* Created on 2007年1月1日, 下午4:57 n|3ENN
* #(!>
* To change this template, choose Tools | Options and locate the template under "M1[@xog
* the Source Creation and Management node. Right-click the template and choose @/XA*9]l
* Open. You can then make changes to the template in the Source Editor. fnwtD*``
*/ F}.<x5I-;h
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package com.tot.count; I=|b3-
import tot.db.DBUtils; tecCU[O
import java.sql.*; hQPiGIs
/** XkOsnI8n
* i,Yv
* @author 9>\s81^
*/ b=`h""u
public class CountControl{ ~[ isR|>
private static long lastExecuteTime=0;//上次更新时间 05.^MU?^U
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )"wWV{k
/** Creates a new instance of CountThread */ -+ -@Yq$
public CountControl() {} 591Syyy
public synchronized void executeUpdate(){ "{j4?3f)
Connection conn=null; eDgRYa9\
PreparedStatement ps=null; ?nCG:\&;'=
try{ pjWqI6,
conn = DBUtils.getConnection(); LZ}C{M{=5A
conn.setAutoCommit(false); (
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9}jF]P*Q
for(int i=0;i<CountCache.list.size();i++){ >2,x#RQs
CountBean cb=(CountBean)CountCache.list.getFirst(); ON\_9\kv
CountCache.list.removeFirst(); 'eZUNX
ps.setInt(1, cb.getCountId()); J9zSBsp_
ps.executeUpdate();⑴ %sbDH
//ps.addBatch();⑵ nB WVG
} p,Qr9p3y
//int [] counts = ps.executeBatch();⑶ >@rsh-Z
conn.commit(); c54oQ1Q&"
}catch(Exception e){ ;1A4p`)
e.printStackTrace(); yk,o*g
} finally{
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try{ 7q^osOj"
if(ps!=null) { $&I##od
ps.clearParameters(); S{zi8Oc6
ps.close(); I_oJx
ps=null; (Xi?Y/
} D({%FQ"
}catch(SQLException e){} #Huvn4x
DBUtils.closeConnection(conn); pMe'fC~*
} MOKg[j
} 0V@u]
public long getLast(){ c-(,%0G0
return lastExecuteTime; pPu E-EDk
} Np$pz
public void run(){ odD^xg"L
long now = System.currentTimeMillis(); kG^DHEne
if ((now - lastExecuteTime) > executeSep) { T;IaVMFG|d
//System.out.print("lastExecuteTime:"+lastExecuteTime); x$tx!%,)/S
//System.out.print(" now:"+now+"\n"); FO&U{(Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K?8{y
lastExecuteTime=now; k^:)|Z
executeUpdate(); 8vOKm)[%
} c,:xm=&
else{ aqSHo2]DX9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^OnU;8IC
} \!Cix}}1
} p'M5]G
} [#.E=s+&
//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 m-dyvW+
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类写好了,下面是在JSP中如下调用。 0&mOu #l
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<% TL-sxED,,D
CountBean cb=new CountBean(); (sHqzWh
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); y0k*iS
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CountCache.add(cb); GsA/pXx
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); jeXv)}
c.run(); 1JMEniB+9
out.print(CountCache.list.size()+"<br>"); p%pM3<p
%>