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: 66/Z\H^d
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CountBean.java ,oBlJvm
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/* cZ^wQ5=
* CountData.java q5%2WM]6
* Tj Mb>w9
* Created on 2007年1月1日, 下午4:44 F|,6N/;!W
* ^)|&|
* To change this template, choose Tools | Options and locate the template under &j3`
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* the Source Creation and Management node. Right-click the template and choose kmIoJH5
* Open. You can then make changes to the template in the Source Editor. BlL|s=dlQV
*/ wjL|Z8
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package com.tot.count; R_7
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/** expxp#S
* p7s@%scp
* @author Og=[4?Kpk
*/ \WcB9
public class CountBean { `n6/ A)
private String countType; #hpIyy%n
int countId; 3!>/smb!
/** Creates a new instance of CountData */ U{"f.Z:Ydo
public CountBean() {} >jv\Qh
public void setCountType(String countTypes){ F%Kp9I*
this.countType=countTypes; z/weit
} *
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public void setCountId(int countIds){ m#*h{U$
this.countId=countIds; TiQ^}5~M
} -xz|ayn
public String getCountType(){ sllzno2bU
return countType; A])OPqP{
} @^'$r&M
public int getCountId(){ 7(NXCAO81
return countId; &-=K:;x
} 3|zgDA
} <~N%W#z/
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CountCache.java 7u::5 W-q
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/* Hng!'
* CountCache.java .9OFryo
* @ ICbKg:
* Created on 2007年1月1日, 下午5:01 +qhnP$vIe
* Z["BgEJ
* To change this template, choose Tools | Options and locate the template under 0vn[a,W<A
* the Source Creation and Management node. Right-click the template and choose S.W^7Ap
* Open. You can then make changes to the template in the Source Editor. F?cq'd
*/ S7CV
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package com.tot.count; -TTs.O8P|<
import java.util.*; {OCJ(^8i
/** Yy hny[fa9
* =T4u":#N;
* @author 'B`#:tX^N
*/ iX%n0i
public class CountCache { E M Q4yK
public static LinkedList list=new LinkedList(); \_9rr6^"
/** Creates a new instance of CountCache */
#9\THfb
public CountCache() {} #uKWuGz]
public static void add(CountBean cb){ &\^rQi/tf
if(cb!=null){ RLHYw@-j@
list.add(cb); 036[96t,F
} '_0
} 3;l "=#5
} SO3cY#i
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CountControl.java .,M;huRg
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/* G6Nb{m
* CountThread.java 6,+nRiZ
* W5Zqgsy($F
* Created on 2007年1月1日, 下午4:57 XYAmJ
* rwgsXS8W6
* To change this template, choose Tools | Options and locate the template under [PWL<t::c
* the Source Creation and Management node. Right-click the template and choose Qxt@V
* Open. You can then make changes to the template in the Source Editor. -DCa
*/ wf9z"B
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package com.tot.count; z"UPyW1?
import tot.db.DBUtils; O('Nn]wo~9
import java.sql.*; mCdgKr|n
/** ;^ 3$kF
* BJ5}GX!
* @author w4%AJmt
*/ E\$C/}T
public class CountControl{ CW`!}yu%
private static long lastExecuteTime=0;//上次更新时间 nIBFk?)6
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @;Y~frT
/** Creates a new instance of CountThread */ KOSQQf
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public CountControl() {} O+"ac /r
public synchronized void executeUpdate(){ tsv$ r$Se
Connection conn=null; %|+E48
PreparedStatement ps=null; 5<+KR.W
try{ .:9s}%Zr
conn = DBUtils.getConnection(); %e_"CS
conn.setAutoCommit(false); 1*UNsEr
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); j *3}1L4P
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); ZnfNQl[
CountCache.list.removeFirst(); v\%G|8+]
ps.setInt(1, cb.getCountId()); ; Lql_1
ps.executeUpdate();⑴ 8l>CR#%@C
//ps.addBatch();⑵ BX< dSK
} E\ th%q,mG
//int [] counts = ps.executeBatch();⑶ GEe`ZhG,
conn.commit(); fn}UBzED\
}catch(Exception e){ Bs!4H2@{(]
e.printStackTrace(); Uyx&E?SlEq
} finally{ >/^#Drwb!i
try{ x0Z5zV9
if(ps!=null) { /:[2'_Xl
ps.clearParameters(); p#@Z$gTH`'
ps.close(); I1"MPx{
ps=null; Em^(
} a07=tD
}catch(SQLException e){} mT.e>/pa
DBUtils.closeConnection(conn); $nPAm6mH
} (^n*Am;zlH
} thW<
public long getLast(){ :&w{\-0{
return lastExecuteTime; h(' )"
} 9|WV~
public void run(){ ..<3%fL3
long now = System.currentTimeMillis(); PQ U]l"A
if ((now - lastExecuteTime) > executeSep) { H0*,8i5I
//System.out.print("lastExecuteTime:"+lastExecuteTime); )^O-X.1
//System.out.print(" now:"+now+"\n"); v:|(8Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r\M9_s8
lastExecuteTime=now; ra6o>lI(,
executeUpdate(); w4:\N U
} SO?8%s(
else{ yR71%]*.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); q4k@l
} S h4wqf
} #kmh:P
} b~0N^p[&%
//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 H+C6[W=
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类写好了,下面是在JSP中如下调用。 xN0*8
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<% XcfKx@l
CountBean cb=new CountBean(); :@3Wg3N
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); X% {'<baR
CountCache.add(cb); 0GXO&rCG
out.print(CountCache.list.size()+"<br>"); 8E^@yZo{
CountControl c=new CountControl(); #-#NqX:
c.run(); *r,b=8|
out.print(CountCache.list.size()+"<br>"); Iy7pt~DJ,
%>