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 ;P&OX5~V
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/* 7i1q wRv
* CountData.java 7 x?<*T
* 8kDp_si
* Created on 2007年1月1日, 下午4:44 b*Q&CL
* "G9xMffW
* To change this template, choose Tools | Options and locate the template under ?#Q #u|~
* the Source Creation and Management node. Right-click the template and choose F^fdIZx
* Open. You can then make changes to the template in the Source Editor. 2T[9f;jM'
*/ $a ` G
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package com.tot.count; &XUiKnNW
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/** >~+ELVB&
* {P#|zp 4C{
* @author U\!X,a*ts{
*/ CQDkFQq-dq
public class CountBean { -1ub^feJ,
private String countType; *bpD`s
@
int countId; @2v_pJy^
/** Creates a new instance of CountData */ =rX>1
public CountBean() {} IRqy%@)
public void setCountType(String countTypes){ d4z/5Oa
this.countType=countTypes; X+]G-
} 3%=~)7cF
public void setCountId(int countIds){ G'aDb/
this.countId=countIds; tcog'nAz
} }?v )N).kW
public String getCountType(){ Z>#i**
return countType; 2Q:+_v
} Fh9h,'
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public int getCountId(){ 4#hSJ(~7S
return countId; gt w Q-
} dzrio-QU~
} r^ ZEImjc
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CountCache.java K8Y=S12Ti
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/* $\y'IQ%
* CountCache.java @bP)406p
* i,9)\1R
* Created on 2007年1月1日, 下午5:01 vd4ytC
* PXNh&N
* To change this template, choose Tools | Options and locate the template under )q3p-)@kQ
* the Source Creation and Management node. Right-click the template and choose 6<(.4a?
* Open. You can then make changes to the template in the Source Editor. fXQNHZ|4
*/ i&GH/y
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package com.tot.count; %sQ^.` 2
import java.util.*; e6RPIg
/** C8i^P}y
* *<ewS8f*6
* @author Alw3\_X
*/ %z4Nl$\
public class CountCache {
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public static LinkedList list=new LinkedList(); l0A&9g*l2
/** Creates a new instance of CountCache */ mUF,@>o
public CountCache() {} p0<\G
public static void add(CountBean cb){ <B8!.|19
if(cb!=null){ iTU5l5U z
list.add(cb); fkNbS
} e'D&8z_;
} 3WIk
} O/(xj2~$J
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CountControl.java 3n}?bY8@5_
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/* '$zIbQ:
* CountThread.java ]+:^W^bs:
* (;^syJrh
* Created on 2007年1月1日, 下午4:57 _/5H l`
* Pw!MS5=r
* To change this template, choose Tools | Options and locate the template under Otm0(+YB7
* the Source Creation and Management node. Right-click the template and choose E\pL!c
* Open. You can then make changes to the template in the Source Editor. \&gB)czEO
*/ HEc+;O1<
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package com.tot.count; X1vd'>
import tot.db.DBUtils; M{hg0/}sUW
import java.sql.*; qR+!l(
/** 3fQuoQuD"}
* Dy8r 9
* @author 6MdiY1Lr!K
*/ agW@{c
public class CountControl{ UH/\
private static long lastExecuteTime=0;//上次更新时间 ,f;}|d:r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2Dj%,gaR
/** Creates a new instance of CountThread */ ~|xA4u5LG
public CountControl() {}
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public synchronized void executeUpdate(){ )+t0:GwP`:
Connection conn=null; H-f X(9
PreparedStatement ps=null;
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try{ *>qp:;,DKP
conn = DBUtils.getConnection(); H@8sNV/u
conn.setAutoCommit(false); M, mvys$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L"Olwwmk
for(int i=0;i<CountCache.list.size();i++){ PxkOT*
CountBean cb=(CountBean)CountCache.list.getFirst(); GD_hhDyD
CountCache.list.removeFirst(); 2{G:=U
ps.setInt(1, cb.getCountId()); 2n"V}p>8i#
ps.executeUpdate();⑴ |T)6yDL
//ps.addBatch();⑵ :^3LvPM
} g0ly
//int [] counts = ps.executeBatch();⑶ ve2u=eQ1
conn.commit(); @xYlS5{
}catch(Exception e){ k4y'b
e.printStackTrace(); %
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} finally{ 1gN=-AC
try{ }"!I[Ek> y
if(ps!=null) { r/6o \-
ps.clearParameters(); tQYM&6g
ps.close(); +@k+2?]
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ps=null; d8=x0~7
} cI?8RF(;
}catch(SQLException e){} dNL(G%Qj+"
DBUtils.closeConnection(conn); M>ruKHipFE
} @8rx`9
} G@jZ)2
public long getLast(){ :~N-.#
return lastExecuteTime; ly_HWuFJ3
} TXvI4"&
public void run(){ K\6u9BYG
long now = System.currentTimeMillis(); !sW(wAy?o
if ((now - lastExecuteTime) > executeSep) { s %\-E9
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//System.out.print("lastExecuteTime:"+lastExecuteTime); v"XGC i91L
//System.out.print(" now:"+now+"\n"); y0.8A-2:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .Cl:eu,]
lastExecuteTime=now; !1{e|p
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executeUpdate(); q0R -7O(
} EkNunCls
else{ @?
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); jeH~<t{
} E`de7
} n'kG] Q
} =Bhe'.]QSx
//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 aa#Y=%^
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类写好了,下面是在JSP中如下调用。 EZ$>.iy{
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<% #S*/bao#
CountBean cb=new CountBean(); |\IN.W[EL
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); K<Iv:5-2
CountCache.add(cb); Ne{?:h.!
out.print(CountCache.list.size()+"<br>"); '2nhv,|.U
CountControl c=new CountControl(); *XbEiMJ
c.run(); ]<rkxgMW>
out.print(CountCache.list.size()+"<br>"); oO|KEY(
%>