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: JmPHAUd
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CountBean.java MG[o%I96
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/* +lJG(Qd
* CountData.java ${+ @gJ+S
* cU0s
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* Created on 2007年1月1日, 下午4:44 9[1`jtm
* 3mYiQ2
* To change this template, choose Tools | Options and locate the template under i%ZW3MrY~
* the Source Creation and Management node. Right-click the template and choose 5V5%/FUm
* Open. You can then make changes to the template in the Source Editor. TftHwe):V
*/ +SsK21f"r
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package com.tot.count; +# GQ,
k:JrHBKv\
/** k9$K}
* gT$Ju88
* @author ~7Ts_:E-
*/ f>aEkh6u9
public class CountBean { #Xhdn\7
private String countType; P/xKnm~
int countId; R16'?,
/** Creates a new instance of CountData */ K#*reJ}K
public CountBean() {} !lEY=1nHOJ
public void setCountType(String countTypes){ >wb'QzF:
this.countType=countTypes; (ohq0Y
} lrnyk(M}Q.
public void setCountId(int countIds){ *F
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this.countId=countIds; /TZOJE(2j
} Qi_>Mg`x
public String getCountType(){ U Z.=aQ}M
return countType; r)Ap8?+
} V2$h8\a
public int getCountId(){ !6s"]WvF
return countId; b'J'F;zh>
} t=_J9|
} M%1}/!J3
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CountCache.java A/s>PhxV
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/* AK\$i$@6
* CountCache.java +|bmT
* #[zI5)Meh
* Created on 2007年1月1日, 下午5:01 ZZcEt
* R&|mdY8
* To change this template, choose Tools | Options and locate the template under W5?yy>S6N
* the Source Creation and Management node. Right-click the template and choose Vy*:ne
* Open. You can then make changes to the template in the Source Editor. Xv<B1
*/ 5O~HWBX.
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package com.tot.count; j6>.n49_
import java.util.*; .u:81I=w(
/** {.Z}5K
* 5WC+guK7
* @author [|P!{?A43|
*/ A;/-u<f
public class CountCache { }:u~K;O87
public static LinkedList list=new LinkedList(); FL(6?8zK
/** Creates a new instance of CountCache */ (S xR`QP?,
public CountCache() {} vFE;D@bz:
public static void add(CountBean cb){ ta`N8vnf
if(cb!=null){ }e2(T
list.add(cb); PUo/J~ v
} p3]_}Y
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} #+$G=pS'v
} ?*?RP)V
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CountControl.java sXi=70o
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/* y]J89
* CountThread.java WcHgBbNe
* 0{dz5gUde
* Created on 2007年1月1日, 下午4:57 #ggf' QIHp
* kqce[hgs<
* To change this template, choose Tools | Options and locate the template under p"l3e9&'j
* the Source Creation and Management node. Right-click the template and choose 3l3+A+n
* Open. You can then make changes to the template in the Source Editor. %=?cZfFqO
*/ pY_s*0_
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package com.tot.count; DA2}{
import tot.db.DBUtils; UilMv~0
import java.sql.*; R,9[hNHWGs
/** T :/,2.l
* 3 n'V\Hvz
* @author L]d-hs
*/ ]%BWIqbr
public class CountControl{ dxZu2&gi
private static long lastExecuteTime=0;//上次更新时间 S,<EEtXQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 UJfEC0
/** Creates a new instance of CountThread */ YqPQ%
public CountControl() {} uq,
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public synchronized void executeUpdate(){ x~GQV^(l3
Connection conn=null; {"&SJt[%X
PreparedStatement ps=null; /1x,h"T\<
try{ A5i :x$ww
conn = DBUtils.getConnection(); ~zSCg|"r
conn.setAutoCommit(false); @+9<O0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -1ce<nN
for(int i=0;i<CountCache.list.size();i++){ ]u4Hk?j~<
CountBean cb=(CountBean)CountCache.list.getFirst(); K_2|_MLlZ
CountCache.list.removeFirst(); EL8NZ%:v:
ps.setInt(1, cb.getCountId()); E<C&Cjz:H
ps.executeUpdate();⑴ U Z|HJ8_
//ps.addBatch();⑵ dbOdq
} W
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T]!
//int [] counts = ps.executeBatch();⑶ z I+\Oll#Q
conn.commit(); \MjJ9u `8
}catch(Exception e){ NPd%M
e.printStackTrace(); u%]shm
} finally{ 2gzou|Y
try{ y`$Q\}fS
if(ps!=null) { FBpH21|/y
ps.clearParameters(); l5g$vh\aQ]
ps.close(); U5-@2YcH
ps=null; d'/TdVM
} J|X
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}catch(SQLException e){} $ &P>r
DBUtils.closeConnection(conn); [5uRS}!
} _R.B[\r@
} 8F:e|\SB#
public long getLast(){ HcedE3Rg
return lastExecuteTime; ]S(%[|
} /[ 6j)HIS
public void run(){ jS+AGE?5e
long now = System.currentTimeMillis(); s/7 A7![
if ((now - lastExecuteTime) > executeSep) { yv\#8I:qh
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9*E7}b,
//System.out.print(" now:"+now+"\n"); txcf=)@>V
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `2`\]X_A{
lastExecuteTime=now; ] )F7)
executeUpdate(); @BrMl%gV
} x7vctjM|
else{ u`olW%C/T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yuDZ~0]R
} TYlbU<
} {X*^s5{;H
} ;b`[&g
//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 ?W0)nQU
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类写好了,下面是在JSP中如下调用。 j:,NE(DF
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<% hSK;V<$[Z
CountBean cb=new CountBean(); ,oNOC3U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M)+$wp
CountCache.add(cb); e]T`ot#/
out.print(CountCache.list.size()+"<br>"); C=s1R;"H
CountControl c=new CountControl(); !A>z(eIsv`
c.run(); ?UK|>9y}Z
out.print(CountCache.list.size()+"<br>"); lj{VL}R
%>