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: aFw \w>*^
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CountBean.java h4ozwVA
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/* !#y_vz9
* CountData.java +-X
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* ,{6Vf|?
* Created on 2007年1月1日, 下午4:44 )x5t']w`K
* 4yK{(!&i+
* To change this template, choose Tools | Options and locate the template under +L0Jje>Az
* the Source Creation and Management node. Right-click the template and choose f/PqkHF
* Open. You can then make changes to the template in the Source Editor. N=T 0Td
*/ Kj53"eW
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package com.tot.count; h-.xx4D
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/** Lm&BT)*
* l4bLN
* @author po9f[/s'+o
*/ -kk0zg
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public class CountBean { [_HY6gr
private String countType; Y;)l
int countId; ;IOM3'5T@
/** Creates a new instance of CountData */ f/95}6M
public CountBean() {} j
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public void setCountType(String countTypes){ 6%^A6U
this.countType=countTypes; P(%^J6[>
} u']}Z%A9`
public void setCountId(int countIds){ k3+LP7|*
this.countId=countIds; 0gRm LX
} 1'B& e)
public String getCountType(){ ;e)`Cv
return countType; ;RK;kdZ
} &j}:8Tst
public int getCountId(){ BaVooN~C
return countId; =28ZSo^
} ?WP *At0
} ^ 0.` 1$
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CountCache.java }Y"vUl_I2
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/* LzTdi%u$0|
* CountCache.java Hp>_:2O8s
* HDO_r(i
* Created on 2007年1月1日, 下午5:01 <KX fh
* }U'VVPh_
* To change this template, choose Tools | Options and locate the template under OF} ."a
* the Source Creation and Management node. Right-click the template and choose %At.nlss
* Open. You can then make changes to the template in the Source Editor. Q7#t#XM
*/ dsU'UG7L
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package com.tot.count; Ot+Z}Z-
import java.util.*; )DGJr/)
/** "+M0lGTB
* |LRAb#F\
* @author GdYQq.
*/ d@%PTSX
public class CountCache { <Nk:C1Op}
public static LinkedList list=new LinkedList(); K&VMhMVb
/** Creates a new instance of CountCache */ <0!<T+JQ
public CountCache() {} bU \T
public static void add(CountBean cb){ I~GHx5Dk
if(cb!=null){ Hqtv`3g
list.add(cb); )(9[> _+40
} Ft^X[5G4L
} Jcy+(7lE)
} p9 G{Q
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CountControl.java WMa`!Q
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/* 6e S~*
* CountThread.java LJ6L#es2
* ~/qBOeU3
* Created on 2007年1月1日, 下午4:57 3a|pk4M
* h1H$3TpP
* To change this template, choose Tools | Options and locate the template under &hUEOif
* the Source Creation and Management node. Right-click the template and choose \.'[!GE *c
* Open. You can then make changes to the template in the Source Editor. 0|<9eD\I=
*/ vb|
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package com.tot.count; ^xgqs $`7
import tot.db.DBUtils; Vr@tSc&
import java.sql.*; gFd*\Dk
/** |c>.xt~
* DheQcM
* @author $h}5cl
*/ CZE!@1"<{
public class CountControl{ u* G+=aV.6
private static long lastExecuteTime=0;//上次更新时间 g^}C/~b[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 W] WH4.y
/** Creates a new instance of CountThread */ +eO>> ~Z
public CountControl() {} "Zy:q'`o
public synchronized void executeUpdate(){ LJ6l3)tpD
Connection conn=null; zwU1(?]I{
PreparedStatement ps=null; *+XiBho
try{ +/bD9x1H
conn = DBUtils.getConnection(); qRR%aJ/
conn.setAutoCommit(false); dBwoAq`'
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +v~x_E5FP
for(int i=0;i<CountCache.list.size();i++){ bU[_YuJbM
CountBean cb=(CountBean)CountCache.list.getFirst(); d}%-vm} 0
CountCache.list.removeFirst(); ftKL#9,s(
ps.setInt(1, cb.getCountId()); ;%Px~g
ps.executeUpdate();⑴ NG`Y{QT6N
//ps.addBatch();⑵ =XtQ\$Pax
} ^ir)z@P?V
//int [] counts = ps.executeBatch();⑶ !9{UBAh
conn.commit(); O._\l?m
}catch(Exception e){ R58NTPm
e.printStackTrace(); F2\&rC4v
} finally{ 9|3sNFGX
try{ ExQ\qp3
if(ps!=null) { fC3T\@(&
ps.clearParameters(); UCXRF
ps.close(); xHqF_10S#
ps=null; SME9hS$4
} ?pcbso
}catch(SQLException e){} N:CQ$7T{ j
DBUtils.closeConnection(conn); *dxm|F98
} =@pD>h/~
} sgDSl@lB
public long getLast(){ BY&{fWUo
return lastExecuteTime; ?68~ g<d,
} icX4n
public void run(){ c1r+?q$f
long now = System.currentTimeMillis(); m)LI|
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if ((now - lastExecuteTime) > executeSep) { jO/cdLKX(
//System.out.print("lastExecuteTime:"+lastExecuteTime); Faa>bc~E
//System.out.print(" now:"+now+"\n"); b;{"@b,Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Zk/ejhy0
lastExecuteTime=now; s7HKgj
executeUpdate(); ^{{a
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}
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else{ Bz <I7h
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W9pY=9]p+
} nF_q{e7
} AorY#oq
} 1Y&W>p
//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 -EE'xh-zD
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类写好了,下面是在JSP中如下调用。
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<% i39ZBs@
CountBean cb=new CountBean(); <i4]qO(0u
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /t<
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CountCache.add(cb); o[}Dj6e\t
out.print(CountCache.list.size()+"<br>"); [\#ANA"
CountControl c=new CountControl(); G0|}s&$yL
c.run(); R<Mc+{*>
out.print(CountCache.list.size()+"<br>"); +7o1&D*v
%>