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: BwN0!lsF3
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CountBean.java y B81f
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/* H9Gh>u]}
* CountData.java RF?`vRZOe
* sbfuzpg]*
* Created on 2007年1月1日, 下午4:44 O0*p0J
* F;Spi
* To change this template, choose Tools | Options and locate the template under ` _6C{<O
* the Source Creation and Management node. Right-click the template and choose H-!,yte
* Open. You can then make changes to the template in the Source Editor. 8v6(qBK
*/ 6lZ3tdyNo
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package com.tot.count; (fhb0i-
"syI#U{
/** n.}Zk G0`
* xf'V{9*
* @author "-E\[@/
*/ &.F4b~A7
public class CountBean { SjK
private String countType; <q)#
int countId; av(6wht8
/** Creates a new instance of CountData */ 3RUy,s
public CountBean() {} fQ7V/x!
public void setCountType(String countTypes){ eYc$dPE
this.countType=countTypes; 8 %:Iv(UMk
} 2/U.|*mH
public void setCountId(int countIds){ qRu~$K
this.countId=countIds; 5f rX
} 9v#CE!
public String getCountType(){ k<z)WNBf
return countType; :S]\0;8]
} 5G}?fSQ>
public int getCountId(){ Q1lyj7c#x
return countId; M+oHtX$
} ~\r*
} HGl|-nW>
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CountCache.java \a<wKTkn
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/* |o7[|3:M
* CountCache.java xKbXt;l2
* SA:Zc^aV
* Created on 2007年1月1日, 下午5:01 r[e##M
* (xycJ`N
* To change this template, choose Tools | Options and locate the template under ?C]vS_jAh
* the Source Creation and Management node. Right-click the template and choose ??5Q)Erm1
* Open. You can then make changes to the template in the Source Editor. pG_;$8Hc
*/ k``_EiV4t
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package com.tot.count; y4yhF8E>;U
import java.util.*; ^"E^zHM(
/** L]7=?vN=8
* ip\sXVR
* @author z>xmRs
*/ rDtY[
public class CountCache { =&6eM2>P
public static LinkedList list=new LinkedList(); JhYe6y[q
/** Creates a new instance of CountCache */ Z<oaK
public CountCache() {} *9
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public static void add(CountBean cb){ MyOd,vU
if(cb!=null){ -au^;CM
list.add(cb); xl{=Y< ;
} 5#6|j?_a
} :x3QRF
} 'I|v[G$l
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CountControl.java 39c2pV[
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/* _=>He=v/
* CountThread.java P-[-pi@
* #I.+aV+2oQ
* Created on 2007年1月1日, 下午4:57 `6;?9NI
* e
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* To change this template, choose Tools | Options and locate the template under + SzU
* the Source Creation and Management node. Right-click the template and choose 3qgS&js 7
* Open. You can then make changes to the template in the Source Editor. kb%;=t2
*/ A.F%Ycq
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package com.tot.count; ?Rb9|`6
import tot.db.DBUtils; 4X/-4'
import java.sql.*; 3=#<X-);
/** E#RDqL*J
* e}voV0y\v:
* @author
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*/ q~Hn-5H4Q
public class CountControl{ y
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private static long lastExecuteTime=0;//上次更新时间 Mc
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]2A^1Del
/** Creates a new instance of CountThread */ ;7*[Bcj.
public CountControl() {} + /G2fhE
public synchronized void executeUpdate(){ {L971W_L
Connection conn=null; 2YL?,uLS
PreparedStatement ps=null; U)TUOwF
try{ KRbvj
conn = DBUtils.getConnection(); c2SO3g\"i
conn.setAutoCommit(false); >dXGee>'M
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); e)IzQ7Zex
for(int i=0;i<CountCache.list.size();i++){ >IafUy
CountBean cb=(CountBean)CountCache.list.getFirst(); _rMg}F"
CountCache.list.removeFirst(); AF{\6<m
ps.setInt(1, cb.getCountId()); yZ7&b&2nLn
ps.executeUpdate();⑴ (y'hyJo
//ps.addBatch();⑵ Y;eZ9|Ht9
} ^S<Y>Nm]
//int [] counts = ps.executeBatch();⑶ ho{*Cjv
conn.commit(); n6=By|jRh
}catch(Exception e){ Wb,KjtX
e.printStackTrace(); },?kk1vIT{
} finally{ f^ZRT@`O
try{ >~rTqtKd
if(ps!=null) { Oxnp0 s
ps.clearParameters(); `cn#B
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ps.close(); 2ACCh4(/P
ps=null; H H)!_(SA
} _%Bi: HG0
}catch(SQLException e){} &3>)qul
DBUtils.closeConnection(conn); m,28u3@r
} ;]puq
} _RYxD"my
public long getLast(){ 'c&Ed
return lastExecuteTime; T.F!+
} QhFVxCA
public void run(){ "9uKtQS0o
long now = System.currentTimeMillis(); .<?GS{6
N
if ((now - lastExecuteTime) > executeSep) { yF:1( 4
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8,Z_{R#|
//System.out.print(" now:"+now+"\n"); Tb}4wLu
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Rh2+=N<X
lastExecuteTime=now; OKZV{Gja
executeUpdate(); PNhe
} A|[?#S((]
else{ @u+]aI!`-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); eeg)N1\
} fb7; |LF
} G>_*djUf
} ]#<4vl\
//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 ]EbM9Fo-U
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类写好了,下面是在JSP中如下调用。 eIF5ZPSZi
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<% je-!4r,
CountBean cb=new CountBean(); 5pG}Yk_(x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); tFn)aa~L
CountCache.add(cb); n8 0?N}
out.print(CountCache.list.size()+"<br>"); JG.y,<xW
CountControl c=new CountControl(); )m+W
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c.run(); +^ac'Y)A
out.print(CountCache.list.size()+"<br>"); P:S .~Jq
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