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: ~&E|;\G
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CountBean.java $D,m o2I
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/* +{%@kX<V_
* CountData.java +n1jP<[<N
* ^iaeY
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* Created on 2007年1月1日, 下午4:44 vBUl6EmWu
* ,+p&ZpH
* To change this template, choose Tools | Options and locate the template under Bx(+uNQ
* the Source Creation and Management node. Right-click the template and choose )p.+39]{2
* Open. You can then make changes to the template in the Source Editor. x,9fOA
*/ eYL7G-3
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package com.tot.count; j/zD`ydj
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/** TO\%F}m(
* 5io7!%
* @author Z&mV1dxR
*/ NJYx.TL
public class CountBean { uO$ujbWZ
private String countType; qZ!1>`B
int countId; \!UNale
/** Creates a new instance of CountData */ S"|sD|xOb
public CountBean() {} &77]h%B>
public void setCountType(String countTypes){ ivdw1g|)h
this.countType=countTypes; {Y5h*BD>
} my#qmI
public void setCountId(int countIds){ FNZB M
this.countId=countIds; _/[n/"gn
} l<<G".?
public String getCountType(){ C9-9cdW
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return countType; UI~ENG
} }9C5U>?
public int getCountId(){ "X']_:F1a
return countId; 9X&Xs/B
} >/"XX,3
} H*QN/{|RU
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CountCache.java R|Ft@]
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/* nf< <]iHf
* CountCache.java TJtW?c7
* @S~'m;
* Created on 2007年1月1日, 下午5:01 `
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* zIbl[[M&
* To change this template, choose Tools | Options and locate the template under BfOG e!Si
* the Source Creation and Management node. Right-click the template and choose =erA.u
* Open. You can then make changes to the template in the Source Editor. Vvx(7p-GQ
*/ X7kJWX
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package com.tot.count; Q:+Y-&||"
import java.util.*; K*J8(/WkD
/** D<7S
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* OU=9fw
* @author $52Te3n
*/ *f8,R"]-g
public class CountCache { C!w@Naj
public static LinkedList list=new LinkedList(); T4
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/** Creates a new instance of CountCache */ a73b/_zZ=
public CountCache() {} ^&uWAQohL
public static void add(CountBean cb){ NrvS/cI!t
if(cb!=null){ '4sT+q
list.add(cb); ZLvw]N&R
} #f|-l$a)3a
} 1elx~5v1.=
} y_"GMw
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CountControl.java I#l9
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/* OxF\Hm)(
* CountThread.java ZNB*Azi
* ./<3jf :
* Created on 2007年1月1日, 下午4:57 lGB7(
* #py7emu
* To change this template, choose Tools | Options and locate the template under >/n5=RWh
* the Source Creation and Management node. Right-click the template and choose V`69%35*@
* Open. You can then make changes to the template in the Source Editor. se_zCS4Y
*/ =Ak>2
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package com.tot.count; af{;4Cr
import tot.db.DBUtils; LWbWj ^
import java.sql.*; MC#bo{Bq3-
/** gb(\c:yg1R
* @
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* @author S=aXmz<
*/ ~Y)Au?d(a
public class CountControl{ 3:Co K#
private static long lastExecuteTime=0;//上次更新时间 =mqV&FgRo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lO,
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/** Creates a new instance of CountThread */ z,rWj][P
public CountControl() {} ~73"AWlp
public synchronized void executeUpdate(){ #`"'
Connection conn=null; 81W})q8
PreparedStatement ps=null; W&06~dI1!
try{ 8Z3+S)6
conn = DBUtils.getConnection(); y8+?:=N.
conn.setAutoCommit(false); ?5mVC]W?]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =X&h5;x'
for(int i=0;i<CountCache.list.size();i++){ `?JrC3
CountBean cb=(CountBean)CountCache.list.getFirst(); #<'/sqL
CountCache.list.removeFirst(); Rl5}W\&
ps.setInt(1, cb.getCountId()); N#.IpY'7Ze
ps.executeUpdate();⑴ +G/~v`Bv
//ps.addBatch();⑵ e^'?:j
} M`?/QU~
//int [] counts = ps.executeBatch();⑶ \f66ipZK*
conn.commit(); g8kw|BgnL
}catch(Exception e){ /LSiDys
e.printStackTrace(); >4EcV1y
} finally{ |P?8<8p
try{ wuYo@DDU#
if(ps!=null) { l}Xmm^@)
ps.clearParameters(); ?7&VT1
ps.close(); WgPL4D9=
ps=null; 3C,e>zE}
} 5 (H; x74
}catch(SQLException e){} ==FzkRA)
DBUtils.closeConnection(conn); X_!mZ\H7
} 30H:x@='9
} %\b5)p
public long getLast(){ +}+hTY$a
return lastExecuteTime; M2xUs
} bkOm/8k|4
public void run(){ j|aT`UH03
long now = System.currentTimeMillis(); E"G._<3J8
if ((now - lastExecuteTime) > executeSep) { ?tA-`\E
//System.out.print("lastExecuteTime:"+lastExecuteTime); Y" l!3^
//System.out.print(" now:"+now+"\n"); r kD4}jV
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); bfpW^y
lastExecuteTime=now; >a4Bfnf"eI
executeUpdate(); zV80r+y
} :&:>sd(QD
else{ p`d:g
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]hf4= gm
} k6Tpaf^
} S'@"a%EV
} kT$4X0}
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Cn`%
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类写好了,下面是在JSP中如下调用。 Cza)s
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<% O3BU.X1'%
CountBean cb=new CountBean(); to?"{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z:fhq:R(
CountCache.add(cb); U_8I$v-~
out.print(CountCache.list.size()+"<br>"); d?{2A84S
CountControl c=new CountControl(); 8c/Ii"1
c.run(); nVM`&azD
out.print(CountCache.list.size()+"<br>"); 73<iK]*c
%>