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: 6S_y%8Fv&[
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CountBean.java M c@GH
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/* 2[BA(B
* CountData.java lA4hm4"i(,
* `]hCUaV
* Created on 2007年1月1日, 下午4:44 x@ 6\Ob
* R.UumBM
* To change this template, choose Tools | Options and locate the template under \^m.dIPdO
* the Source Creation and Management node. Right-click the template and choose H%~Q?4
* Open. You can then make changes to the template in the Source Editor. Gt5$6>A
*/ r./z,4A`
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package com.tot.count; k -]xSKG
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/** J=VyyUB
* .h!9wGi`
* @author ?N2X)Y@yi
*/ fOJj(0=y
public class CountBean { L"9 Gc
private String countType; -P*xyI
int countId; ;h~?ko
/** Creates a new instance of CountData */ l&$*}yCK
public CountBean() {} 5(KG=EHj_
public void setCountType(String countTypes){ B'!PJj
this.countType=countTypes; 0|GpZuGO9
} E2-ojL[6
public void setCountId(int countIds){ g"w)@*?K
this.countId=countIds; :"y0oCu7`W
} 98jD"*W5
public String getCountType(){ _>;&-e
return countType; \!m!ibr
} ~DK F%}E
public int getCountId(){ N JXa_&_
return countId; JUmw$u
} hzW{_Q.|?
} S\}?zlV
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CountCache.java Jm%mm SYK
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/* <r0.ppgY
* CountCache.java ^P]?3U\nj
* qjJ{+Rz2
* Created on 2007年1月1日, 下午5:01 a4Ls^
* umqLKf=x!
* To change this template, choose Tools | Options and locate the template under >7"$}5d
* the Source Creation and Management node. Right-click the template and choose _s2m-jm7
* Open. You can then make changes to the template in the Source Editor. yi sF5`+
*/ ;HR 6X
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package com.tot.count; Wk7L:uK
import java.util.*; 7s0)3HR}
/** Ng?apaIi@~
* -mE
* @author Fecx';_1`
*/ bcUC4g\9N
public class CountCache { 0Z@ARMCe|m
public static LinkedList list=new LinkedList(); #Tup]czO
/** Creates a new instance of CountCache */ Y>xi|TWN
public CountCache() {} '.=Wk^,Ua
public static void add(CountBean cb){ iTj"lA
if(cb!=null){ )!'Fa_$ e
list.add(cb); V h
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} Rrh<mo(yj#
} Lhl$w'r
} av'd%LZP
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CountControl.java Oqd"0Qt-
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/* Pz5ebhgq
* CountThread.java GS$ZvO
* b`(yu.{Jn
* Created on 2007年1月1日, 下午4:57 %'RI3gy
* *p" "YEN
* To change this template, choose Tools | Options and locate the template under %KbBH:z05
* the Source Creation and Management node. Right-click the template and choose R4&|t
* Open. You can then make changes to the template in the Source Editor. y%{*uH}SL
*/ #[gcg]6c
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package com.tot.count; l9M#]*{
import tot.db.DBUtils; z*Myokhf
import java.sql.*; ?)Tz'9l
/** DQ}_9?3
* 7xLo4
* @author 3%It~o?
*/ p_rN1W
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public class CountControl{ ;FV~q{
private static long lastExecuteTime=0;//上次更新时间 wJapGc!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Uq9,(tV`6g
/** Creates a new instance of CountThread */ 9f@#SB_H
public CountControl() {} D)H?=G
public synchronized void executeUpdate(){ yRgDhA
Connection conn=null; >XD02A[
PreparedStatement ps=null; GCf._8;%
try{ *Gk<"pEeS
conn = DBUtils.getConnection(); O0K@M
conn.setAutoCommit(false); |% M{kA-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); C5:dO\?O
for(int i=0;i<CountCache.list.size();i++){ }Q{
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CountBean cb=(CountBean)CountCache.list.getFirst(); H3
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CountCache.list.removeFirst(); zPX=MfF
ps.setInt(1, cb.getCountId()); ;a!h.8UJPI
ps.executeUpdate();⑴ %4|n-`:
//ps.addBatch();⑵ 2.HZ+1
} WU+Jo@]y
//int [] counts = ps.executeBatch();⑶ *@\?}cX
conn.commit(); NPB ,q& Th
}catch(Exception e){ o*O"\/pmF
e.printStackTrace(); oW
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} finally{ s8f3i\1
try{ tj"v0u?zW
if(ps!=null) { ]X>QLD0W
ps.clearParameters(); aIzp\$NWVK
ps.close(); +LQs.*
ps=null; P-E'cb%ub
} 5CH-:|(;=
}catch(SQLException e){} `>`K7-H
DBUtils.closeConnection(conn); 4y]: Gqz~
} JR?
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} Ab^>z
public long getLast(){ 1A`?y&
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return lastExecuteTime; r2E>sHw
} }C`}wS3i
public void run(){ )"pxry4v7J
long now = System.currentTimeMillis(); 0aTEJX$iZ
if ((now - lastExecuteTime) > executeSep) { !SO$k%b}!
//System.out.print("lastExecuteTime:"+lastExecuteTime); W[1f]w3
//System.out.print(" now:"+now+"\n"); T;4gcJPn"M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ig.6[5a\
lastExecuteTime=now; Zgy2Pot
executeUpdate(); @??c<]9F
} UuOLv;v
else{ _ RT"1"r
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); SSL%$:l@
} RV#uy]
} u]]5p[|S
} v8'`gY
//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 "j.oR}s9?#
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类写好了,下面是在JSP中如下调用。 {'c%#\
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<% o7@4=m}
CountBean cb=new CountBean(); [:R P9r}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LDi ezi
CountCache.add(cb); R.2KYhp,
out.print(CountCache.list.size()+"<br>"); x3I%)@-Z
CountControl c=new CountControl(); lU50.7<08
c.run(); mtWx ?x
out.print(CountCache.list.size()+"<br>");
f_5R!;
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