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: [(*?
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CountBean.java ,racmxnv
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/* 'w?}~D.y
* CountData.java >,a$)z
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* Created on 2007年1月1日, 下午4:44 ):7mK03J
* .qS(-7<
* To change this template, choose Tools | Options and locate the template under hj,y l&
* the Source Creation and Management node. Right-click the template and choose NM+(ss'
* Open. You can then make changes to the template in the Source Editor. U# U*^#
*/ Hv-f :P O
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package com.tot.count; sw+vyBV)r
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/** 7'.]fs:
* 7f>~P_
* @author 0SV4p.
*/ {ep.So6
public class CountBean { Kp>fOe'KW
private String countType; gN.n_!
int countId; Y(F>;/AA
/** Creates a new instance of CountData */ <+_WMSf;4
public CountBean() {} >E9 k5
public void setCountType(String countTypes){ 2?@Ozr2Uh
this.countType=countTypes; rw.DKM'
} %+@<T<>J<k
public void setCountId(int countIds){ a/xnf<(H
this.countId=countIds; .4[M7)
} =0mn6b9-=
public String getCountType(){ -{ES 36
return countType; T
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} ?*&5`Xh
public int getCountId(){ `]F#j ]"
return countId; [:8+ +#KD
} X3m)
} 8*^*iEsR
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CountCache.java C(n_*8{
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/* -nqq;|%
* CountCache.java
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* 10CRgrZ
* Created on 2007年1月1日, 下午5:01 g\pLQH
* %ZX3:2
* To change this template, choose Tools | Options and locate the template under !:Ob3Mq\
* the Source Creation and Management node. Right-click the template and choose :"gu=u!
* Open. You can then make changes to the template in the Source Editor. :@~mN7O*
*/ .V@3zzv\
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package com.tot.count; A().1h1_k
import java.util.*; oj[<{/,C9
/** -'T^gEd)c
* |xrnLdng0R
* @author NmTo/5s
*/ 8;O /x
public class CountCache { IU\h,Ug
public static LinkedList list=new LinkedList(); o,'Fz?[T%
/** Creates a new instance of CountCache */ <sG}[:v
public CountCache() {} JZ/T:Hsh4
public static void add(CountBean cb){ HqXS-TG
if(cb!=null){ VBz
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list.add(cb); L=&}s[5
} T=':$(t
} W8M(@*
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} %v[KLMo'(
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CountControl.java |}Z2YDwO/
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/* ])?[9c
* CountThread.java xXCsJ9]
* *mn"GK6
* Created on 2007年1月1日, 下午4:57 S}6xkX
* @ssT$#)$!
* To change this template, choose Tools | Options and locate the template under \{={{O
* the Source Creation and Management node. Right-click the template and choose ,%U\@*6=
* Open. You can then make changes to the template in the Source Editor. =oTj3+7
*/ YwZ]J
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package com.tot.count; 3\K;y>NK
import tot.db.DBUtils; 9>;CvR
import java.sql.*; @ X5#?
/** OV`li#H
* Nb)Mh
* @author WQMoAPfqL
*/ luJNdA:t&
public class CountControl{ Wz;@Rl|F
private static long lastExecuteTime=0;//上次更新时间 b{;LbHq+G
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 o w;a7
/** Creates a new instance of CountThread */ 6u xF<
public CountControl() {} PNH>LT^
public synchronized void executeUpdate(){ 1^2]~R9,9
Connection conn=null; `t+;[G>ZE
PreparedStatement ps=null; AJ
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try{ b^"mQ
conn = DBUtils.getConnection(); TWdhl9Ot
conn.setAutoCommit(false); ,m M7g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Lm+E? Ca
for(int i=0;i<CountCache.list.size();i++){ NT{'BJ
CountBean cb=(CountBean)CountCache.list.getFirst(); l@`n4U.Gwl
CountCache.list.removeFirst(); \_7'f
ps.setInt(1, cb.getCountId()); umt(e:3f5
ps.executeUpdate();⑴ oSl}A,aQ(
//ps.addBatch();⑵ u]P9ip"Z
} d}wE4(]b
//int [] counts = ps.executeBatch();⑶ |(uo@-U
conn.commit(); t-Ble
}catch(Exception e){ G<Urj+3/Xo
e.printStackTrace(); QT4vjz+|
} finally{ Y6a9S`o
try{ CKX3t:HP0
if(ps!=null) { *r ('A
ps.clearParameters(); 5kCXy$"%
ps.close(); HC"yC;_
ps=null; CHDt^(oa!B
} 4wx{i6
}catch(SQLException e){} oo1h"[
DBUtils.closeConnection(conn); ;8cTy8
} DIgur}q)@
} Th4}$)yrkN
public long getLast(){ gFXz:!A
return lastExecuteTime; J\Tu=f)
} TXqtE("BDl
public void run(){ rpEN\S%7P
long now = System.currentTimeMillis(); #<es>~0!
if ((now - lastExecuteTime) > executeSep) { fIn^a3TV
//System.out.print("lastExecuteTime:"+lastExecuteTime); :bkmm,%O
//System.out.print(" now:"+now+"\n"); sIRfC<
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N w/it*f
lastExecuteTime=now; xF*i+'2
executeUpdate(); - x; xQ
} HT6$|j
else{ m@YK8c#$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'Jd*r(2d
} UDPn4q
} Kp19dp}'b
} Dn`
//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 \/-4 jF:
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类写好了,下面是在JSP中如下调用。 B[d%?L_
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<% t(}g;O-
CountBean cb=new CountBean(); 9zm2}6r4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (IIZ vCek
CountCache.add(cb); EtQ:x$S_
out.print(CountCache.list.size()+"<br>"); D$VRE^k
CountControl c=new CountControl(); gP>W* ]0r1
c.run(); BE!l{
out.print(CountCache.list.size()+"<br>"); Y/
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%>