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: jx=2^A/i2-
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CountBean.java <.d0GD`^
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/* KL4Z||n
* CountData.java D/jS4'$vA
* @'K+
* Created on 2007年1月1日, 下午4:44 e:BKdZGW
* CPI7&jqu
* To change this template, choose Tools | Options and locate the template under hE-u9i
* the Source Creation and Management node. Right-click the template and choose N o}Ly{
* Open. You can then make changes to the template in the Source Editor. @nJ#kd[
*/ e3L<;MAt
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package com.tot.count; ^[d|^fRH Q
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/** jocu=Se@
* 4Qr16,Us
* @author Z'%k`F
*/ X3KPN
public class CountBean { C#5z!z/:%
private String countType; C?Sy90f
int countId; ]<0|"NL
/** Creates a new instance of CountData */ t._W643~
public CountBean() {} <tEN1i
public void setCountType(String countTypes){ Ou
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this.countType=countTypes; CbJ ]}Z
} |WiK*
public void setCountId(int countIds){ /&>6#3df-
this.countId=countIds; Um
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} BO b#9r
public String getCountType(){ Ny;(1N|&3
return countType; &b 2Vt
} (~r"N?`
public int getCountId(){ o3hsPzOQx
return countId; o0>z6Ya<
} uC>X;<^
} 1RtbQ{2F;
* Yr)>;^
CountCache.java g`jO
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/* 29?{QJb
* CountCache.java /x6,"M[97
* r@3VN~
* Created on 2007年1月1日, 下午5:01 `N~;X~XFk
* npH2&6Yhi^
* To change this template, choose Tools | Options and locate the template under uvK1gJrA)
* the Source Creation and Management node. Right-click the template and choose R}Ih~zw
* Open. You can then make changes to the template in the Source Editor. |wKC9 O@%
*/ CQo<}}-o
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package com.tot.count; "lo:"y(u
import java.util.*; Uk u~"OGC
/** ?qviJDD|f
* `e
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* @author P9/5M4]tt
*/
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public class CountCache { z?HP%g'M~
public static LinkedList list=new LinkedList(); Y~T;{&wi
/** Creates a new instance of CountCache */ K .cMuh
public CountCache() {} H|4O`I;~(
public static void add(CountBean cb){ ]q0mo1-EZ!
if(cb!=null){ 5FJ<y"<6
list.add(cb); ZZf-c5 g
} :7t~p&J
} ?|8H|LBIr
} ^+zF;Q'
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CountControl.java 3_W1)vd{
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/* |?CR|xqT
* CountThread.java !M&L<0b:7e
* /O1r=lv3Z
* Created on 2007年1月1日, 下午4:57 0/d+26lR
* 33lD`4i+
* To change this template, choose Tools | Options and locate the template under <wge_3W#
* the Source Creation and Management node. Right-click the template and choose ~3Y)o|D3
* Open. You can then make changes to the template in the Source Editor. H gMLh*
*/ +53 Tf
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package com.tot.count; ZPWY0&9
import tot.db.DBUtils; ~^QL"p:5|
import java.sql.*; 3jIi$X06
/** =dD<[Iz6
* ?b0 VB
* @author %D|27gh
*/ \}Jy=[
public class CountControl{ *hVW>{a
private static long lastExecuteTime=0;//上次更新时间 lBS!=/7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4oT1<n`r+
/** Creates a new instance of CountThread */ wSHE~Xx
public CountControl() {} $9dm2#0d
public synchronized void executeUpdate(){ D.H$4[u;j
Connection conn=null; wt4uzg8
PreparedStatement ps=null; |;o#-YosP
try{ 9"g=it2Rh6
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); &B\tcF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F gM<2$h
for(int i=0;i<CountCache.list.size();i++){ "ZDc$v:Qa
CountBean cb=(CountBean)CountCache.list.getFirst(); N.OC _H&
CountCache.list.removeFirst(); wkK61ah6
ps.setInt(1, cb.getCountId()); 0[@9f1Nk4
ps.executeUpdate();⑴
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//ps.addBatch();⑵ $:kG>R@\t
} cQ~}qE>I
//int [] counts = ps.executeBatch();⑶ $}0q=Lg%wv
conn.commit(); ">]v'h(s
}catch(Exception e){ YB/A0 J
e.printStackTrace(); n*G[ZW*Uc
} finally{
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try{ TSXa#SKp
if(ps!=null) { k;PQVF&E
ps.clearParameters(); DQM\Y{y|3
ps.close(); $F-qqkR$
ps=null; <:)T7yVq
} S8mqz.
}catch(SQLException e){} Q#8}pBw
DBUtils.closeConnection(conn); w}VS mt$F
} R4G$!6Ld
} qepsR/0M
public long getLast(){ l$D]*_ jc,
return lastExecuteTime; >|%m#JG
} D4[1CQ@}4D
public void run(){ ItGi2'}
long now = System.currentTimeMillis(); y*A#}b*0
if ((now - lastExecuteTime) > executeSep) { 6]^;
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//System.out.print("lastExecuteTime:"+lastExecuteTime); i,N U%be
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K0RY2Hiw
lastExecuteTime=now; .a\b_[+W
executeUpdate(); DytH} U"
} u"r~5
else{ pOQ'k>!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sJ)XoK syW
} ,:UoE
} Z- ;<R$
} <@xp. Y
//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 ;}{xpJ/
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类写好了,下面是在JSP中如下调用。 I`kaAOe
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<% pASNiH698
CountBean cb=new CountBean(); VH7VJ [
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #y13(u,dN
CountCache.add(cb); #4"(M9kf
out.print(CountCache.list.size()+"<br>"); $6w[h7
CountControl c=new CountControl(); !qPVC\l
c.run(); YlDui8.N
out.print(CountCache.list.size()+"<br>"); P]:r'^Yn
%>