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: gfs?H #
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CountBean.java Qsc%qt-l
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/* @
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* CountData.java jYRwtP\
* |jniI(
* Created on 2007年1月1日, 下午4:44 t+5JIQY>
* K<KyX8$P0
* To change this template, choose Tools | Options and locate the template under iU\WV
* the Source Creation and Management node. Right-click the template and choose g#;w)- Zj
* Open. You can then make changes to the template in the Source Editor. mh!;W=|/"
*/ 2`Xy}9N/Y
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package com.tot.count; Ex~[Hk4ow
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/** GH![rK
* ^PfFW
* @author z{cI G8z
*/ O/>$kG%ge
public class CountBean { yK<%AV@v
private String countType; AxUj CerNf
int countId; 1_THBL26d
/** Creates a new instance of CountData */ c.Pyt
public CountBean() {} .
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public void setCountType(String countTypes){ _* ] ~MQ=
this.countType=countTypes; H3}{]&a
} #vYdP#nWb
public void setCountId(int countIds){ [L8Bgw1
this.countId=countIds; 3HC aZ?Ry'
} qCn(~:
public String getCountType(){ ^$DpdzI
return countType; ~oh=QakW
}
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public int getCountId(){ Zi[@xG8dm
return countId; ?&ThMWl
} b40zYH`'{
} a1B_w#?8
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CountCache.java 4r`u@
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/* 7\'vSHIL
* CountCache.java ?h"+q8&
* bWo-(
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* Created on 2007年1月1日, 下午5:01 V6?ku6k
* 0#KDvCBJ
* To change this template, choose Tools | Options and locate the template under [S9T@Q
* the Source Creation and Management node. Right-click the template and choose 8E"Ik~
* Open. You can then make changes to the template in the Source Editor. hV])\t=yf
*/ hWwh`Vw%
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package com.tot.count; 11}X2j~Ww
import java.util.*; _ro^<V$%
/** ;(fD R8
* a33}CVG-e3
* @author }:7'C. ."
*/ ttuQ,SD
public class CountCache { B1oi]hDy
public static LinkedList list=new LinkedList(); O E0w/{
/** Creates a new instance of CountCache */ >xws
public CountCache() {} A1zM$
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public static void add(CountBean cb){ \:]Clvc
if(cb!=null){ N%%2!Z#
list.add(cb); \RyOexNZ
} -gefdx6ES
} u;p{&\(]
} &duWV6Acw
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CountControl.java ^&buX_nlO
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/* %eB 0)'
* CountThread.java B*p`e1
* ~q4KQ&.!
* Created on 2007年1月1日, 下午4:57 >Lx,<sE
* ]/hF!eO
* To change this template, choose Tools | Options and locate the template under C']TO/2q
* the Source Creation and Management node. Right-click the template and choose %yX?4T;b
* Open. You can then make changes to the template in the Source Editor. oa$-o/DhB
*/ ma[%,u`
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package com.tot.count; W~(@*H
import tot.db.DBUtils; Xptb4]
import java.sql.*; a|rN %hA4
/** . > [d:0
* PnkJWl<S
* @author ".A+'pJ
*/ lx$]f)%~
public class CountControl{ ]Ir{9EE
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private static long lastExecuteTime=0;//上次更新时间 al/Mgo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6t/nM
/** Creates a new instance of CountThread */ $Wt0e 4YSu
public CountControl() {} u U Xj
public synchronized void executeUpdate(){ IZ+kw.6e
Connection conn=null; =<Q_&_.60
PreparedStatement ps=null; ,(&jG^IpVJ
try{ Y|JC+Ee
conn = DBUtils.getConnection(); gv)F`uRWA
conn.setAutoCommit(false); 3SI:su
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VQ wr8jXye
for(int i=0;i<CountCache.list.size();i++){ eD5:0;X2
CountBean cb=(CountBean)CountCache.list.getFirst(); P7ktr?V0a
CountCache.list.removeFirst(); 8>^(-ca_
ps.setInt(1, cb.getCountId()); V@krw"vW
ps.executeUpdate();⑴ ${I$@qq83
//ps.addBatch();⑵ n[DQ5l
} XRoMD6qf;
//int [] counts = ps.executeBatch();⑶ vxuxfi8x
conn.commit(); dQP7CP
}catch(Exception e){ %B9iby8)1
e.printStackTrace(); GjTj..G/
} finally{ VGFWF3s
try{ j7r! N^
if(ps!=null) { ,K4*0!TXP
ps.clearParameters(); `"~s<+
ps.close(); )D_ZZPq_
ps=null; 1$S;#9PQ
} T'YHV}b}vX
}catch(SQLException e){} kg@D?VqJP
DBUtils.closeConnection(conn); x1H?e8
} >6 p
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} _<Hx1l~
public long getLast(){ r=57,P(:Ca
return lastExecuteTime; Ve/"9?Y_
} p#-ov-znp
public void run(){ gFO|)I N
long now = System.currentTimeMillis(); 'p0|wM_
if ((now - lastExecuteTime) > executeSep) { `v2]Jk<
//System.out.print("lastExecuteTime:"+lastExecuteTime); dFdll3bC
//System.out.print(" now:"+now+"\n"); @q=l H
*=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %cIF()
lastExecuteTime=now; 7\ .Ax
executeUpdate(); $lJu2omi1
} , $;g'z!N
else{ t<`h(RczHI
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %y@iA91K
} <9za!.(zu
} ,p(4OZz5,
} eFO+@
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 :V)W?~Z7B
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类写好了,下面是在JSP中如下调用。 o;#{N~4[$
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<% bYzBe\^3q3
CountBean cb=new CountBean(); kBPFk t2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +{%@kX<V_
CountCache.add(cb); ^RN1?dXA
out.print(CountCache.list.size()+"<br>"); DNgQ.lV
CountControl c=new CountControl(); !U02>X
c.run(); E)(`Z0
out.print(CountCache.list.size()+"<br>"); 1'|6IR1'
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