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: {hr>m,O%
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CountBean.java 0l=g$G
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/* G9J+D?'hH
* CountData.java Sz|;wsF{
* P~/Glak
* Created on 2007年1月1日, 下午4:44 MA0}BJoW
* o,dO.isgh>
* To change this template, choose Tools | Options and locate the template under ~UA:_7#\M
* the Source Creation and Management node. Right-click the template and choose +L
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* Open. You can then make changes to the template in the Source Editor. M}2a/}4
*/ gM~dPM|
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package com.tot.count; eT* )r~
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/** MA1.I4dm
* &~Qi+b0!
* @author 5]D"y Ay81
*/ (!`TO{ !6P
public class CountBean { j#mo Vq
private String countType; 7<;87t]]
int countId; <RH2G
/** Creates a new instance of CountData */ /qp)n">
public CountBean() {} nA$zp
public void setCountType(String countTypes){ 1;Bgt v$
this.countType=countTypes; w9h`8pt
} L6S!?t.{Yv
public void setCountId(int countIds){ s|L}wtc
this.countId=countIds; _P9Th#UAg
} ,U':=8
public String getCountType(){ !lf'gW
return countType; X&R,-^
} s3?pv
public int getCountId(){ r/E'#5 Q
return countId; qk!")t
} d(!W
} SKO*x^"eU
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CountCache.java $*a'[Qot#
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/* (ns>z7
* CountCache.java }Fy~DsQ
* |]FJfMX
* Created on 2007年1月1日, 下午5:01 pV`?=[h9
* MD`1KC_m
* To change this template, choose Tools | Options and locate the template under uXD?s3Wv
* the Source Creation and Management node. Right-click the template and choose GR6BpV7
* Open. You can then make changes to the template in the Source Editor. t<~$?tuZ
*/ >HMuh)
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package com.tot.count; zq\YZ:JC
import java.util.*; 2eNA#^T=
/** RE~:+.eB
* t0t" =(d
* @author L9L!V"So1k
*/ 2rK%fV53b
public class CountCache { &,~0*&r0
public static LinkedList list=new LinkedList(); ["]r=l
/** Creates a new instance of CountCache */ rm}OVL
public CountCache() {} Wc]L43u
public static void add(CountBean cb){ lxsBXX Zg
if(cb!=null){ mFoE2?Y
list.add(cb); =^
} OX|nYTp
} L O)&|9xw
} <i}lP/U
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CountControl.java Y [8~M8QX
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/* <*O~?=6p
* CountThread.java QAs$fi}f]s
* wCT. (d_
* Created on 2007年1月1日, 下午4:57 a
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* L#)F00/`
* To change this template, choose Tools | Options and locate the template under :v-&}?
* the Source Creation and Management node. Right-click the template and choose +"8AmN4
* Open. You can then make changes to the template in the Source Editor. ;Oh abbj*
*/ jpg$5jZ
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package com.tot.count; jvGGIb"&1
import tot.db.DBUtils;
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import java.sql.*; %p? +r
/** ean_/E
* i n}N[
* @author ``
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*/ aB@D-Y"HO
public class CountControl{ {{'GR"D
private static long lastExecuteTime=0;//上次更新时间 =Yd{PZ*fR
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p%MH**A
/** Creates a new instance of CountThread */ zT_
public CountControl() {} BT[jD}?
public synchronized void executeUpdate(){ <~wr;"S
Connection conn=null; 5!GL"
PreparedStatement ps=null; fyb:eO}
try{ h?UUd\RU)
conn = DBUtils.getConnection(); T&@xgj|!)
conn.setAutoCommit(false); WKjE^u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d5aG6/
for(int i=0;i<CountCache.list.size();i++){ ){'Ef_/R
CountBean cb=(CountBean)CountCache.list.getFirst(); @D:$~4ks
CountCache.list.removeFirst(); o u%Xnk~
ps.setInt(1, cb.getCountId()); Q[5j5vry
ps.executeUpdate();⑴ TV^m1uC
//ps.addBatch();⑵ h%2;B;p]
} A}./ ;[
//int [] counts = ps.executeBatch();⑶ \J@i:J6x$1
conn.commit(); AC`4n|,zJ;
}catch(Exception e){ Atdr|2
e.printStackTrace(); $?voQ&
} finally{ 5G$sP,n
try{ QOb+6qy:3
if(ps!=null) { R<"fcsU
ps.clearParameters(); `TugtzRU
ps.close(); +@n8DM{b
ps=null; P;B<R"
} H);O. m
}catch(SQLException e){} EMe3Xb
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DBUtils.closeConnection(conn); . \/jy]Y
} s"tyCDc.c
} 12W`7
public long getLast(){ W Z!?O0.A
return lastExecuteTime; gG^A6Ol%D
} Zq,[se'nh"
public void run(){ d<x7* OW)
long now = System.currentTimeMillis(); n+ot. -
if ((now - lastExecuteTime) > executeSep) { rt5FecX\
//System.out.print("lastExecuteTime:"+lastExecuteTime); c,wYXnJ_t
//System.out.print(" now:"+now+"\n"); &Nzq/~uqP
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); NI^=cN,l
lastExecuteTime=now; |@Cx%aEKU
executeUpdate(); BYhF?
} O/Q7{5n
else{ wNNInS6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0[/GEY@
} R&lJ& SgC
} UG@9X/l}
} olHT* mr
//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 2hD(zUSy
c/K:`XP~
类写好了,下面是在JSP中如下调用。 p,(gv])ie
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<% .mr&zq
CountBean cb=new CountBean(); J(0E'o{ug
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); D9hV`fA
CountCache.add(cb); %MA o<,ha
out.print(CountCache.list.size()+"<br>"); 5X4 #T&.
CountControl c=new CountControl(); >#9f{
c.run(); mNc?`G_R
out.print(CountCache.list.size()+"<br>"); [2WJ];FJ
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