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: Zw
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CountBean.java #( J}xz;
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/* 7#.PMyK9
* CountData.java l"y9XO|
* =d.W'q|
* Created on 2007年1月1日, 下午4:44 A2_3zrE
* K5rj!*x.o
* To change this template, choose Tools | Options and locate the template under \1'R}B@;
* the Source Creation and Management node. Right-click the template and choose uN0fWj]
* Open. You can then make changes to the template in the Source Editor. VgoKi
*/ "hY^[@7 W
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package com.tot.count; <U`Nb) &
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/** *t9qH
* vm}.gQ
* @author 1V$B^/ _
*/ ms<u YLp
public class CountBean { zGz'2,o3
private String countType; xm,yqM!0A
int countId; >Mw =}g@P
/** Creates a new instance of CountData */ #f;1f8yrN
public CountBean() {} > BCX%<&
public void setCountType(String countTypes){ Dohe(\C@
this.countType=countTypes; W%Q>< 'c
} >Nl~"J|]q
public void setCountId(int countIds){ >M85xjXP
this.countId=countIds; jAHn`Bxz
} &-Er n/[
public String getCountType(){ yZaDNc9'
return countType; 0%j;yzQ<
} }U1shG[
public int getCountId(){ zb,`K*Z{
return countId; q[A3$y(
} ,.MG&O
} 8>;o MM
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CountCache.java "fd=(&
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/* D ,^
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* CountCache.java \ jdO,-(
* 4tNgK[6M
* Created on 2007年1月1日, 下午5:01 cty#@?"e
* g]JI}O*5
* To change this template, choose Tools | Options and locate the template under {\Y,UANZ
* the Source Creation and Management node. Right-click the template and choose B#n}y
* Open. You can then make changes to the template in the Source Editor. Ps4A
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*/ ` &7?+s
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package com.tot.count; wk/U"@lq
import java.util.*; Q[tz)99~
/** :u93yH6~8
* 0LuY"(LR
* @author -z1o~~
*/ V t;&2v
public class CountCache { j'cCX[i
public static LinkedList list=new LinkedList(); \9Zfu4WR
/** Creates a new instance of CountCache */ w*@Z-'(j
public CountCache() {} Z9bPj8d
public static void add(CountBean cb){ S]@iS[|?
if(cb!=null){ K%_JQ0`
list.add(cb); ,{t!->K
} ?IO/zkeXg
} !gQ(1u|r
} hmk5
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CountControl.java vtjG&0GSK
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/* >g=:01z9
* CountThread.java sOenR6J<$
* )+R3C%
* Created on 2007年1月1日, 下午4:57 Gl1$W=pR:
* 5|z[%x~f
* To change this template, choose Tools | Options and locate the template under $7g(-W
* the Source Creation and Management node. Right-click the template and choose ^@eCT}p{
* Open. You can then make changes to the template in the Source Editor. 'o9V0#$!
*/ Y:BrAa[
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package com.tot.count; {a%cU[q
import tot.db.DBUtils; FQ^uX]<3j
import java.sql.*; ^S$w,
/** mt7:`-
* :7*\|2zA
* @author r${a
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*/ <!$Cvx\U
public class CountControl{ wt,N<L
private static long lastExecuteTime=0;//上次更新时间 {
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 m!if_Iq
/** Creates a new instance of CountThread */ K?WqAVK
public CountControl() {} .<hv&t
public synchronized void executeUpdate(){ l>q.BG
Connection conn=null; :g_ +{4
PreparedStatement ps=null; d^>s e'ya
try{ Id1[}B-T
conn = DBUtils.getConnection(); -2?fg
conn.setAutoCommit(false); 2N#L'v@g=+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2V 'Tt3
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); (>23[;.0
CountCache.list.removeFirst(); G9Ezm*I;:
ps.setInt(1, cb.getCountId()); ST.W{:X
ps.executeUpdate();⑴ GV/FK{v5
//ps.addBatch();⑵ RzRLrfV
} ' 'N@ <|
//int [] counts = ps.executeBatch();⑶ j+seJg<_
conn.commit(); )I_I?e
}catch(Exception e){ af{K4:I
e.printStackTrace();
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} finally{ G&-h,"yo^
try{ Stpho4+/y
if(ps!=null) { ) 'KHUa9
ps.clearParameters(); Uy=eHwU?J
ps.close(); "w1jr 6"
ps=null; f}4h}Cq
} QB>e(j%
}catch(SQLException e){} !s:|Ddv
DBUtils.closeConnection(conn); @"0qS:s]X
} aleIy}"
} 2{\Y<%.
public long getLast(){ }_x oT9HUr
return lastExecuteTime; 8%B @[YDe
} zwS'AN'A
public void run(){ __ [q`
long now = System.currentTimeMillis(); M"V@>E\L
if ((now - lastExecuteTime) > executeSep) { dl4.jLY
//System.out.print("lastExecuteTime:"+lastExecuteTime); L2%P
//System.out.print(" now:"+now+"\n"); DTY=k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %iNDRLR%I
lastExecuteTime=now; ;MD{p1w
executeUpdate(); 3 -FNd~%
} `)fGw7J
{
else{ usip>y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xPv&(XZR
} nq;)!Wry
} U_?RN)>j
} oR }
//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 A{vG@Pwc:
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类写好了,下面是在JSP中如下调用。 +TX]~k79Oq
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<% tz{]H9
CountBean cb=new CountBean(); ADDp m-]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -rfO"D>
CountCache.add(cb); V !$m{)Y
out.print(CountCache.list.size()+"<br>"); i%iU_`
CountControl c=new CountControl(); 0=iJT4IEJ
c.run(); W~4|Z=f
out.print(CountCache.list.size()+"<br>"); KpL82
%>