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: -yTIv*y
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CountBean.java 3+vVdvu%
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/* bI_MF/r''
* CountData.java @; I9e
* #!%zf{(C+
* Created on 2007年1月1日, 下午4:44 Oamz>Hplu
* ^dsj1#3z
* To change this template, choose Tools | Options and locate the template under ]ms+Va_/
* the Source Creation and Management node. Right-click the template and choose 1L!jI2~x}
* Open. You can then make changes to the template in the Source Editor. L6;'V5Mg72
*/ LGVy4D
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package com.tot.count; pU[yr'D.r
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/** WK@<#
* s&<76kwl
* @author 5tzO=gO[
*/ <`NsX
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public class CountBean { 5hDy62PRr
private String countType; fO
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E}
int countId; B@VAXmCaoV
/** Creates a new instance of CountData */ G;/l[mvh,
public CountBean() {} g+c%J#F=
public void setCountType(String countTypes){ <P6d-+
this.countType=countTypes; AT1{D!b
} ;:+2.//
public void setCountId(int countIds){ n}fV$qu
this.countId=countIds; TeO'E<@
} kHhku!CH
public String getCountType(){ ^U96p0H"T
return countType; e@ $|xa")
} oA7| s1
public int getCountId(){ h@\HPYi#.
return countId; b!`Ze~V
} r.6?|
} ,?Zy4-
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CountCache.java i\gt
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/* `&xdS H
* CountCache.java Uj3HAu
* 8lS
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* Created on 2007年1月1日, 下午5:01 -T-yt2h(
* AZA5>Y
* To change this template, choose Tools | Options and locate the template under DUH_LnHw)
* the Source Creation and Management node. Right-click the template and choose Dhfor+Epy
* Open. You can then make changes to the template in the Source Editor. \pTv;(
*/ {XUSw8W'
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package com.tot.count; [?;L
import java.util.*; YnW9uy5
/** mFxt +\
* <F"G~.^ *s
* @author ?4Fev_5m
*/ 5p5"3m;M7
public class CountCache { e"XolM0IM
public static LinkedList list=new LinkedList(); Wm5[+z|2?9
/** Creates a new instance of CountCache */ QnS#"hc\a
public CountCache() {} 8G|?R#&
public static void add(CountBean cb){ m({q<&]Qp
if(cb!=null){ q;IuV&B
list.add(cb); d6-q"
} Q2* 8c$
} pSIXv%1J
} %L7DC`
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CountControl.java \Y!=O=za]
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/* P4c3kO0
* CountThread.java 8>D*U0sNl
* ]#rV]As
* Created on 2007年1月1日, 下午4:57
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* 4^4T#f2=e
* To change this template, choose Tools | Options and locate the template under RL/7>YQ
* the Source Creation and Management node. Right-click the template and choose ua &uR7
* Open. You can then make changes to the template in the Source Editor. 1/qD5 *`Y
*/ _bg Zl
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package com.tot.count; d(R8^v/L
import tot.db.DBUtils; Fm6]mz%~u#
import java.sql.*; GK6CnSV8d
/** x!pd50-
* )1R[X!KQ7
* @author Tyb'p9
*/ 0Q8iX)
public class CountControl{ g}K/ba'
private static long lastExecuteTime=0;//上次更新时间 ,1lW`Krx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 '&K' 0qG
/** Creates a new instance of CountThread */
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public CountControl() {} X}C8!LA
public synchronized void executeUpdate(){ .*>C[^
Connection conn=null; X.,R%>O}`P
PreparedStatement ps=null; l[m*csDk"
try{ 3pL4Zhf
conn = DBUtils.getConnection(); R[fQ$` M
conn.setAutoCommit(false); c'Z)uquvP
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); TL7qOA7^X
for(int i=0;i<CountCache.list.size();i++){ 6"}F
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CountBean cb=(CountBean)CountCache.list.getFirst(); EM+! ph
CountCache.list.removeFirst(); 0b8=94a{>
ps.setInt(1, cb.getCountId()); yv>uzb`N
ps.executeUpdate();⑴ i.?rom
//ps.addBatch();⑵ _4#7 ? p
} DAORfFG74
//int [] counts = ps.executeBatch();⑶ u(?U[pe[
conn.commit(); bJR\d0Z
}catch(Exception e){ k]RQ 7e
e.printStackTrace(); 7v0VZ(UR
} finally{ wgvCgr<
try{ ^nOh8L;
if(ps!=null) { H_Sv,lwz;c
ps.clearParameters(); P*PJ
ps.close(); :P+7ti@
ps=null; f4NN?"W)
} vS3Y9|-:
}catch(SQLException e){} V$Oj@vI
DBUtils.closeConnection(conn); U7f
o4y1}
} _+7P"B|\
} g}a+%Obb
public long getLast(){ OPqhdqo
return lastExecuteTime; v@s"*E/PF7
} Z.unCf3Q
public void run(){ Jcs
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long now = System.currentTimeMillis(); .Zs.O/
if ((now - lastExecuteTime) > executeSep) { %]tW2s"
//System.out.print("lastExecuteTime:"+lastExecuteTime); k*F9&-rtN
//System.out.print(" now:"+now+"\n"); iS"6)#a72
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S==0/
lastExecuteTime=now; dXsL0r*c
executeUpdate(); +2Aggv>*
} l^}5PHLd
else{ EqIs&){
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {BaPK&x,
} =T?Xph{
} i??+5o@uTF
} HxLuJ
//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 c*"P+
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类写好了,下面是在JSP中如下调用。 Txpj#JD
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<% {`J!DFfur
CountBean cb=new CountBean(); "e>9R'y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /;21?o
CountCache.add(cb); cP@H8|c=
out.print(CountCache.list.size()+"<br>"); NxK.q)tj6
CountControl c=new CountControl(); rfSEL
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c.run(); |N
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out.print(CountCache.list.size()+"<br>"); gS]
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