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: #%CbZw@hJ9
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CountBean.java I^iJ^Z]vx
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/* X {,OP/
* CountData.java PI>PEge!&
* ?CB*MWjd
* Created on 2007年1月1日, 下午4:44 mzufl:-=
* %G6ml,
* To change this template, choose Tools | Options and locate the template under %Z@+K_X9x
* the Source Creation and Management node. Right-click the template and choose /+\m7IS
* Open. You can then make changes to the template in the Source Editor. *I;,|Jj k
*/ 6Z~u2&
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package com.tot.count; SFrQPdX6V
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/** =M"H~;f]
* `UFRv
* @author tlw$/tMa
*/ ]>R|4K_
public class CountBean { yT Pi/=G
private String countType; Pl_4;q!$
int countId; 3F' {JP
/** Creates a new instance of CountData */ H`/QhE
public CountBean() {} c"OBm#
public void setCountType(String countTypes){ y2k'^zE
this.countType=countTypes; jU2Dpxkt
} %Gp%l
public void setCountId(int countIds){ ]M
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this.countId=countIds; ,-PzUR4_Kj
} Fw!wSzsk3
public String getCountType(){ Qmxe*@{`
return countType; 70,V>=aJ
} Dm=t`_DL8
public int getCountId(){ ^|^ek
return countId; :34#z.O
} 6AeX$>k+
} -lHSojq~H
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CountCache.java ZD{%0uh
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/*
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* CountCache.java -x~h.s,
* Xg:w;#r,
* Created on 2007年1月1日, 下午5:01 *<k8H5z8]
* ;K<e]RI;?
* To change this template, choose Tools | Options and locate the template under QjH;'OVt
* the Source Creation and Management node. Right-click the template and choose 'N$hbl
* Open. You can then make changes to the template in the Source Editor. o -tc}Aa
*/ |4uH
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package com.tot.count; <.j `n
import java.util.*; OE87&Cl"{t
/** y6.}h9~
* K;jV"R<9
* @author pEk^;
*/ ,Y&LlB 2
public class CountCache { /(C?3}}L
public static LinkedList list=new LinkedList(); ,i>u>YNZ
/** Creates a new instance of CountCache */ 3-cCdn
public CountCache() {} L3:dANG
public static void add(CountBean cb){ b_=$W
if(cb!=null){ O+I\Q?
list.add(cb); +jzwi3B`
} n:JWu0,h
} cW B>
} $0WO
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CountControl.java TWF6YAQm
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/* ^lVZW8
* CountThread.java &$yC+cf
* n4Fh*d ixg
* Created on 2007年1月1日, 下午4:57 cIqk=_]
* aty"6~
* To change this template, choose Tools | Options and locate the template under .`Ey'T_
* the Source Creation and Management node. Right-click the template and choose ?sQOz[ig;
* Open. You can then make changes to the template in the Source Editor. ;,T3C:S?
*/ YXE?b@W"
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package com.tot.count; lz>YjK:
import tot.db.DBUtils; _@I8B
import java.sql.*; C
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/** FqQqjA
* ([~9v@+
* @author E(DNK
*/ 06@^knm
public class CountControl{ oBZ\mk L
private static long lastExecuteTime=0;//上次更新时间 40TS=evG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KL:x!GsV5e
/** Creates a new instance of CountThread */ O@;;GJ
public CountControl() {} =zw=Jp
public synchronized void executeUpdate(){ Sa5+_TW
Connection conn=null; -dXlGOD+C
PreparedStatement ps=null; ^LfN6{
try{ H/8H`9S$
conn = DBUtils.getConnection(); <CrNDY
conn.setAutoCommit(false); N@D]Q&;+(T
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8S2sNpLi-g
for(int i=0;i<CountCache.list.size();i++){ *`~
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CountBean cb=(CountBean)CountCache.list.getFirst(); '6l4MR$j&m
CountCache.list.removeFirst(); ^z&eD,
ps.setInt(1, cb.getCountId()); -2NXQ+m ;
ps.executeUpdate();⑴ ~WH4D+
//ps.addBatch();⑵ 8:9m< ^4S(
} 2xBIfmR^y
//int [] counts = ps.executeBatch();⑶ \)Sa!XLfT
conn.commit(); +<5q8{]Pk
}catch(Exception e){ , &>LBdG`
e.printStackTrace(); .FUws
} finally{ VO#x+u]/
try{ GT$.#};u
if(ps!=null) { s Xyc _3N
ps.clearParameters(); ^0A}iJL
ps.close(); 9Q{-4yF9k
ps=null; y V=Ku
} p=F!)TnJN
}catch(SQLException e){} 5,/rh,?
DBUtils.closeConnection(conn); 3m
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} I'pOB
} 7.7aHt0
public long getLast(){ ~>C@n'\lv
return lastExecuteTime; hY$gzls4
} H CKD0xx
public void run(){ ;Du+C%
long now = System.currentTimeMillis(); 8K: RoR
if ((now - lastExecuteTime) > executeSep) { -$W#bqvz^
//System.out.print("lastExecuteTime:"+lastExecuteTime); Co|3k:I 8
//System.out.print(" now:"+now+"\n"); 0=N,y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >eX&HS oy
lastExecuteTime=now; [
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executeUpdate(); y $,K^f
} = MQpYX
else{ 0ws1S(pq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); SU,S1C_q8
} gc~nT/lfK
} Z)
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} sVdn>$KXk
//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 50,`=Z
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类写好了,下面是在JSP中如下调用。 $~x#Q?-y
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<% R8[l\Y>Ec
CountBean cb=new CountBean(); ?HD(EGdx
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); c6v@6jzx0Y
CountCache.add(cb); &(M][Uo{|'
out.print(CountCache.list.size()+"<br>"); -D=J/5L#5
CountControl c=new CountControl(); _=,\uIrk
c.run(); ,1xX`:
out.print(CountCache.list.size()+"<br>"); #cHH<09rl
%>