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: n84|{l581
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CountBean.java Q%G8U#Tm
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/* f6Ah6tb
* CountData.java D>q9 3;p
* RrB&\9=
* Created on 2007年1月1日, 下午4:44 S\=Nn7"
* )t#W{Gzfmh
* To change this template, choose Tools | Options and locate the template under CdQ!GS<'y
* the Source Creation and Management node. Right-click the template and choose R 9\*#c
* Open. You can then make changes to the template in the Source Editor. 3pKQ$\u
*/ 6_Y,eL]"
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package com.tot.count; bn5 Su=]
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/** ~>|ziHx
* .q>iXE_c
* @author Lf&kv7Wj
*/ $&td=OK
public class CountBean { e"<OELA
private String countType; L0o\J` :
int countId; GTd,n=
/** Creates a new instance of CountData */ ":ue-=&M
public CountBean() {} MTn{d
public void setCountType(String countTypes){ (<9u-HF#
this.countType=countTypes;
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} 4hj|cCrO
public void setCountId(int countIds){ mzgfFNm^G)
this.countId=countIds; Zy/_
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} hgq;`_;1,
public String getCountType(){ @ 6vIap|
return countType; W<g1<z\f
} fJg+ Ryo
public int getCountId(){ H:|uw
return countId; PW0LG^xp`
} oEv'dQ9
} Dd|VMW=
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CountCache.java AK4t\D)K1
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/* TLH1>pY&
* CountCache.java eR>oq,
* Bzf^ivT3L
* Created on 2007年1月1日, 下午5:01 I?CZQ+}Hq
* 'g\4O3&_
* To change this template, choose Tools | Options and locate the template under L4W5EO$
* the Source Creation and Management node. Right-click the template and choose 6=C<>c%+
* Open. You can then make changes to the template in the Source Editor. tw@X>
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*/ RRJ%:5&
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package com.tot.count; e0 ecD3
import java.util.*; 5 qA'
/** |G<|F`Cj
* At;LO9T3z
* @author h?U
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*/ i%?* @uj
public class CountCache { P%n>Tg80M
public static LinkedList list=new LinkedList(); a<e[e>
/** Creates a new instance of CountCache */ SpBy3wd
public CountCache() {} ~xTt204S
public static void add(CountBean cb){ Lg hfM"g
if(cb!=null){ u ga_T
list.add(cb); vY3h3o
} A#,ZUOPGH
} Q>z8IlJ}
} .}+}8[p4l
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CountControl.java %BODkc Zh
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/* "[N!m1i:{
* CountThread.java bN.Pex
* DY*N|OnqJ
* Created on 2007年1月1日, 下午4:57 EU#^7
* 2~V*5~fb
* To change this template, choose Tools | Options and locate the template under lB4WKn=?Kl
* the Source Creation and Management node. Right-click the template and choose 6S#Cl>v
* Open. You can then make changes to the template in the Source Editor. 7yQ4*UB
*/ Lw,h+@0
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package com.tot.count; /-s6<e!
import tot.db.DBUtils; |s_GlJV.
import java.sql.*; LzL
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/** E{(;@PzE
* xIn:ZKJ'
* @author i.#:zU%o
*/ I/N *gy?*
public class CountControl{ j>kqz>3
private static long lastExecuteTime=0;//上次更新时间 `]aeI'[}R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 rm_Nn8p,
/** Creates a new instance of CountThread */
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public CountControl() {} wd6owr
public synchronized void executeUpdate(){ &^nGtW%a 9
Connection conn=null; iy"*5<;*DD
PreparedStatement ps=null; l^}c!
try{ V]^$S"Tv
conn = DBUtils.getConnection(); HaYo!.(Fv
conn.setAutoCommit(false); ;*J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /L3:
for(int i=0;i<CountCache.list.size();i++){ B5QFK
CountBean cb=(CountBean)CountCache.list.getFirst(); 5V-I1B&
CountCache.list.removeFirst(); wIgS3K
ps.setInt(1, cb.getCountId()); Bw.i}3UT6
ps.executeUpdate();⑴ 4p wH>1
//ps.addBatch();⑵ 73-p*o(pt
} FI.\%x
//int [] counts = ps.executeBatch();⑶ X>^fEQq"
conn.commit(); "N#Y gSr
}catch(Exception e){ O.M1@w]
e.printStackTrace(); 6u%&<")4HP
} finally{ 4M T 7 `sr
try{ |j|rS5
if(ps!=null) { Gw` L"
ps.clearParameters(); VEH>]-0K
ps.close(); gGuO
ps=null; 05R@7[GWq
} HOi`$vX}N
}catch(SQLException e){} y`Z\N
DBUtils.closeConnection(conn); Wn6Sn{8W{
} 1;iUWU1@
} ry]l.@o;
public long getLast(){ {8etv:y
return lastExecuteTime; HZOMlOZ
} ?]5qr?W%
public void run(){ OrW
long now = System.currentTimeMillis(); u?EN
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); r_d!ikOT(
//System.out.print(" now:"+now+"\n"); EX"yxZ~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^rz_f{c]-
lastExecuteTime=now; L},_.$I?
executeUpdate(); "
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} >mkFV@`
else{ jWgX_//!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s#MPX3itK
} +|f@^-
} YYS0`
} O0:q;<>z
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 |BYRe1l6l
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类写好了,下面是在JSP中如下调用。 C,zohlpC
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<% kf9X$d6
CountBean cb=new CountBean(); ; @X<lCk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Bp{Ri_&A
CountCache.add(cb); bK7J} 8hH
out.print(CountCache.list.size()+"<br>"); I 6O
CountControl c=new CountControl(); g{LP7D;6
c.run(); )PZT4jTt
out.print(CountCache.list.size()+"<br>"); V~#tuv
%>