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: '"]>`=R
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CountBean.java EM54
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/* yp2 'KES>
* CountData.java ds$ \vSd
* >c
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* Created on 2007年1月1日, 下午4:44 m wEVEx24
* .H(}[eG_
* To change this template, choose Tools | Options and locate the template under iWN.3|r
* the Source Creation and Management node. Right-click the template and choose l`FR.)2h
* Open. You can then make changes to the template in the Source Editor. .)^3t~
*/ G<u.+V
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package com.tot.count; F{*9[jY
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/** j&[3Be'pQ
* oY2?W
* @author "l[V%f E
*/ \|pK Z6*s
public class CountBean { *Nf4bH%MN
private String countType; \p@nH%@v
int countId; V:G }=~+=
/** Creates a new instance of CountData */ uWR,6\_jY
public CountBean() {} lQ<#jxp
public void setCountType(String countTypes){ mWN1Q<vn,l
this.countType=countTypes; M~z(a3@[V
} Q9eYF-+
public void setCountId(int countIds){ \p3nd!OIG
this.countId=countIds; ^E<~zO=Z
} HzG~I8o(d
public String getCountType(){ cEdz;kbUM
return countType; Ic{'H2~4,
} q]iKz%|Z/
public int getCountId(){ @wB'3q}(
return countId; =Y]'5cn{
} gB{]yA"('
} 9#s95RO
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CountCache.java cFI7}#,5
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/* 5}X<(q(
* CountCache.java
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* TRySl5jx@
* Created on 2007年1月1日, 下午5:01 HoIKx_
* hk"9D<&i>b
* To change this template, choose Tools | Options and locate the template under m|nL!Wc
* the Source Creation and Management node. Right-click the template and choose 8tT&BmT
* Open. You can then make changes to the template in the Source Editor. y?Hj%,
*/ >p]WCb'PH
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package com.tot.count; hyk|+z`B
import java.util.*; Z/NGv
/** 75\RG+kQ
* <@U.
* @author [$1: &!(!
*/ qL%.5OCn(
public class CountCache { "LP,
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public static LinkedList list=new LinkedList(); +
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/** Creates a new instance of CountCache */ F=
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public CountCache() {} .y %pGi
public static void add(CountBean cb){ PuCwdTan_
if(cb!=null){ [Hv*\rb
list.add(cb); .-('C> @
} ?dJ/)3I%F
} r&%gjqt
} @O}IrC!bf
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CountControl.java pIZLGsu[
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/* zJnL<Q
* CountThread.java 5T$9'5V7
* %jbJ6c
* Created on 2007年1月1日, 下午4:57 t-*VsPy
* )Y&MIJ7>@
* To change this template, choose Tools | Options and locate the template under GZ/pz+)i&
* the Source Creation and Management node. Right-click the template and choose Gsds!z$
* Open. You can then make changes to the template in the Source Editor. 2y9:'c|
*/ 8X}^~ e
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package com.tot.count; p|&ZJ@3
import tot.db.DBUtils; _Hz~HoNU
import java.sql.*; X[GIOPDx
/** N5q}::Odc
* ou<S)_|Iu
* @author Fe_::NVvk
*/ 38V $ <w
public class CountControl{ 9]]!8_0=r
private static long lastExecuteTime=0;//上次更新时间 hw&ke$Fg#
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H$NP1^5!
/** Creates a new instance of CountThread */ HpB!a,R6B
public CountControl() {} s
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public synchronized void executeUpdate(){ 2gQY8h8
Connection conn=null; 8Zcol$XS'
PreparedStatement ps=null; eVqM=%Q
try{ nuf@}W>y
conn = DBUtils.getConnection(); }Kvh`@CiJ
conn.setAutoCommit(false); c[(yU#@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E/"YId `A
for(int i=0;i<CountCache.list.size();i++){ K)<Wm,tON
CountBean cb=(CountBean)CountCache.list.getFirst(); )LkM,T
CountCache.list.removeFirst(); 8fJR{jD(s
ps.setInt(1, cb.getCountId()); ]%gp?9wy
ps.executeUpdate();⑴ ;Ri 3#*a=
//ps.addBatch();⑵ g8%MOhg
} G*kE~s9R
//int [] counts = ps.executeBatch();⑶ SL[rn<x|
conn.commit(); JfI aOhKs]
}catch(Exception e){ tP}Xhn`
e.printStackTrace(); 8ku?
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} finally{ R<0Fy =z
try{ ry$tK"v/
if(ps!=null) { >}ro[x`K
ps.clearParameters(); MC4284A5
ps.close(); 9uA,
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ps=null; th5,HO~
} [ Z#+gh
}catch(SQLException e){} BhqhyX\D&y
DBUtils.closeConnection(conn); z[WC7hvU
} IkSX\*
} {F;,7Kn+l
public long getLast(){ 4 hL`=[AB
return lastExecuteTime; 6P0y-%[Gk
} TFBYY{Y
public void run(){ J9g|#1G
long now = System.currentTimeMillis(); [yO=S0 e
if ((now - lastExecuteTime) > executeSep) { o)0C-yO0qf
//System.out.print("lastExecuteTime:"+lastExecuteTime); oR-O~_)U
//System.out.print(" now:"+now+"\n"); Z1VC5*K
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); IO}+[%ptc*
lastExecuteTime=now; gsnP!2cR
executeUpdate(); ~RcNZ\2y
} l<u{6o
else{ v2IEJ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MinbE13?U
} [_j6cj]
} lo"j )Zt
} P;j&kuW|zL
//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 u@AI&[Z
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类写好了,下面是在JSP中如下调用。 7*+Km'=M
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<% )\8URc|J
CountBean cb=new CountBean(); qpoquWZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); L_E^}^1!
CountCache.add(cb); +H41]W6
out.print(CountCache.list.size()+"<br>"); <#zwKTmK1
CountControl c=new CountControl(); [.{^" <Z<
c.run(); #]@9qPyn
out.print(CountCache.list.size()+"<br>"); 5(423"(y
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