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: qE{L42
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CountBean.java !+3nlG4cw
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/* 5DVSaI$ =
* CountData.java zB#.EW
* 2%~+c|TH.)
* Created on 2007年1月1日, 下午4:44 c^}DBvG,
* 4siq
* To change this template, choose Tools | Options and locate the template under 18ON`j
* the Source Creation and Management node. Right-click the template and choose _*u$U
* Open. You can then make changes to the template in the Source Editor. $NwPGy?%
*/ !~ZAm3GwL
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package com.tot.count; 7G
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/** }syU(];s
* r.v.y[u
* @author ;~Q`TWC
*/ >ToI$~84
public class CountBean { Lv:;}
private String countType; 9]^NAlno
int countId; a- 7RJ.
/** Creates a new instance of CountData */ SnGXEQ
public CountBean() {} $x(p:+TI\4
public void setCountType(String countTypes){ v)LSH;<
this.countType=countTypes; r/RX|M
} hGU 3DKHT
public void setCountId(int countIds){ Z>ztFU
this.countId=countIds; <l$ vnq
} co>IJzg
public String getCountType(){ (iY2d_FQ[
return countType; 256V
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} QTjnXg?Ri
public int getCountId(){ U]O>DM^'
return countId; eY3<LVAX
} gmtS3,
} MUMB\K*$
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CountCache.java Ej$oRo{IG
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/* @{@)gE
* CountCache.java cs)R8vuB)z
* qDjH^f
* Created on 2007年1月1日, 下午5:01 6Q}>=R^h
* ;rt\
* To change this template, choose Tools | Options and locate the template under cC TTjx{
* the Source Creation and Management node. Right-click the template and choose 8D`TN8[W
* Open. You can then make changes to the template in the Source Editor. Q@cYHFi~+
*/ a!;CY1>
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package com.tot.count; |5\:
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import java.util.*; *):s**BJ$
/** DN|+d{^lN
* r
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* @author /F}dC/W
*/ ^'4I%L"
public class CountCache { X92I==-w
public static LinkedList list=new LinkedList(); kjOI7` DU
/** Creates a new instance of CountCache */ q`L}\}o
public CountCache() {} s~g]`/h$r
public static void add(CountBean cb){ h`Xl~=
if(cb!=null){ 0D}k ^W
list.add(cb); .zvvk
} J&;' gT
} *N%)+-
} 2Kw i4R
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CountControl.java /X?%K't2r
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/* K#dG'/M|Pb
* CountThread.java @mEB=X(-l=
* {hx=6"@
* Created on 2007年1月1日, 下午4:57 j]6YLM@5$
* gflO0$i
* To change this template, choose Tools | Options and locate the template under p
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* the Source Creation and Management node. Right-click the template and choose ,UneS
* Open. You can then make changes to the template in the Source Editor. q5>!.v
*/ [`bA,)y"
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package com.tot.count; ?r^>Vk}
import tot.db.DBUtils; *ub"!}$st
import java.sql.*; c1g'l.XL
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/** (_eM:H=e>
* >%85S >e
* @author U6~79Hnt
*/ (o1o);AO
public class CountControl{ D^A#C<Gs
private static long lastExecuteTime=0;//上次更新时间 C40W@*6S2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T,v5cc:nO
/** Creates a new instance of CountThread */ G[Jz(/yNH
public CountControl() {} TGI`}#
public synchronized void executeUpdate(){ q(}#{OO
Connection conn=null; M[^EHa<i
PreparedStatement ps=null; ? 1Uq ud
try{ ;i&t|5y~
conn = DBUtils.getConnection(); r\m2Oo)]
conn.setAutoCommit(false); !GtCOr\'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 6jz~q~I
for(int i=0;i<CountCache.list.size();i++){ &a";jO
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CountBean cb=(CountBean)CountCache.list.getFirst(); `5Em : 8 M
CountCache.list.removeFirst(); ]!cLFXa
ps.setInt(1, cb.getCountId()); MG74,D.f
ps.executeUpdate();⑴ T@Th?
//ps.addBatch();⑵ BU=Ta$#BZ
} u$+nl~p[&
//int [] counts = ps.executeBatch();⑶ NzbHg p
conn.commit(); MDfC%2Q
}catch(Exception e){
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e.printStackTrace();
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} finally{ +aRHMH
try{ 0Yfz?:e
if(ps!=null) { j Ysg'Rl
ps.clearParameters(); I =nvL
ps.close(); QE`u~
ps=null; '#CYw=S+
} |JTDwmR
}catch(SQLException e){} Tywrh9[
DBUtils.closeConnection(conn); g715+5z[
} "mAMfV0
} VPOp#;"%
public long getLast(){
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return lastExecuteTime; BXLw
} kj'
public void run(){ iayxN5,
long now = System.currentTimeMillis(); }K9Ji]tOK:
if ((now - lastExecuteTime) > executeSep) { 7OLchf
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); ':|?M B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #v:A-u
lastExecuteTime=now; N~9zQ
executeUpdate(); )!d_Td\-
} hr/|Fn+kA
else{ _kQOax{c/
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Z/b,aZhB
} ?,FL"ye
} }Z% j=c"d
} wW0m}L
//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 AI3\eH+
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类写好了,下面是在JSP中如下调用。 !9EbG
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<% pcPRkYT[M
CountBean cb=new CountBean(); Is}?:ET
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0ZtH
CountCache.add(cb); QHe:
out.print(CountCache.list.size()+"<br>"); Y,d|b V*FH
CountControl c=new CountControl(); CpC6vA.R
c.run(); "S3U]zw0_
out.print(CountCache.list.size()+"<br>"); Xb7G!Hk#g
%>