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: AF>t{rw=/
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CountBean.java R{pF IyR
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/* @@ cc/S
* CountData.java }b]eiPWN
* T3@34}*
* Created on 2007年1月1日, 下午4:44 hD{
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* Nh\o39=
* To change this template, choose Tools | Options and locate the template under f{2I2kJr
* the Source Creation and Management node. Right-click the template and choose =MT'e,T
* Open. You can then make changes to the template in the Source Editor. XSGBC:U)l
*/ TX;)}\
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package com.tot.count; ,&L}^ Up
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/** a'A<'(yv
* D@kf^1G
* @author ;=WwJ Np~
*/ '4CD
}
public class CountBean { *K BaKS
private String countType; <v=s:^;C0
int countId; !j}L-1*{ l
/** Creates a new instance of CountData */ 4W}mPeEeV
public CountBean() {} /EuH2cy$l
public void setCountType(String countTypes){ e;2A{VsD8
this.countType=countTypes; >`p?
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} mtdy@=?1Y
public void setCountId(int countIds){ ?!O4ia3nFk
this.countId=countIds; |a%Wd
} hzT)5'_
public String getCountType(){ F|@\IVEB]
return countType; Tgh?=]H
} -hc8IS
public int getCountId(){ Q>71uM%e`
return countId; BGHZL~
} BWNI|pq)v
} SM8_C!h:
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CountCache.java pw`'q(ad
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/* Ks<+@.DLTu
* CountCache.java _07$TC1
* LR';cR;
* Created on 2007年1月1日, 下午5:01 #jd.i
* |(AFU3~
* To change this template, choose Tools | Options and locate the template under O<E8,MCA[a
* the Source Creation and Management node. Right-click the template and choose %k~ezn
* Open. You can then make changes to the template in the Source Editor. +bT[lJ2O>G
*/ X?XB!D7[
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package com.tot.count; X yiaRW
import java.util.*; $HtGB]
/** 9Q!Z9n"8~)
* Ay PtbrO
* @author @DF7j|]tV
*/ ZCViZWo
public class CountCache { 64]8ykRD-
public static LinkedList list=new LinkedList(); @BG].UJo
/** Creates a new instance of CountCache */ `WnsM;1Y"
public CountCache() {} {&UA60~6
public static void add(CountBean cb){ 57=d;Yg e
if(cb!=null){ K:GEC-
list.add(cb); E@yo/S
} j=Izwt>
} +k~0&lZi
} bE{YK
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CountControl.java >239SyC-,
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/* fx>U2
* CountThread.java )W InPW
* x/wgD'?
* Created on 2007年1月1日, 下午4:57 lfre-pS+
* p|8ZHR+
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose \KzJNCOT
* Open. You can then make changes to the template in the Source Editor. +I3O/=)
*/ kD?@nx>
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package com.tot.count; 5[4nFa}R:5
import tot.db.DBUtils; w%8y5v5
import java.sql.*; t
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/** 1U/RMN3`
* )RT?/N W
* @author W]bgWKd
*/ x)GheM^
public class CountControl{ a2tEp+7?
private static long lastExecuteTime=0;//上次更新时间 &0tW{-Hv"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nj1o!+9>$
/** Creates a new instance of CountThread */ ^g5E&0a`g
public CountControl() {} 0zkMRBe
public synchronized void executeUpdate(){ 8A.7q
Connection conn=null; EmR82^_:
PreparedStatement ps=null; .a7RGT3]m
try{ C=]<R<Xy
conn = DBUtils.getConnection(); MkL2I+*
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); U$~6V%e
for(int i=0;i<CountCache.list.size();i++){ G"OP`OMDc
CountBean cb=(CountBean)CountCache.list.getFirst(); DBL@Mp[<
CountCache.list.removeFirst(); d9BFeq8
ps.setInt(1, cb.getCountId()); FO%pdLs,
ps.executeUpdate();⑴ s\pukpf@
//ps.addBatch();⑵ p6K ~b
} 6u lx0$[
//int [] counts = ps.executeBatch();⑶ K@{0]6
conn.commit(); dH
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}catch(Exception e){ nc\`y,>l8
e.printStackTrace(); Wbei{3~$Y"
} finally{ 8'jt59/f
try{ 0<a|=kZ
if(ps!=null) { 2l+L96
ps.clearParameters(); )#cZ&
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ps.close(); nq8XVT.m^\
ps=null; _+NjfF|
} u~ipB*Zf
}catch(SQLException e){} [DH4iG5
DBUtils.closeConnection(conn); $
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} , ?U)mYhI
} NsP=l]
public long getLast(){ \Ta5c31S+
return lastExecuteTime; PJ0~ymE1~G
} EJ#I7_
public void run(){ q,O_y<uw
long now = System.currentTimeMillis(); 4\u`MR
if ((now - lastExecuteTime) > executeSep) { yxHo0U
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,?er AI
//System.out.print(" now:"+now+"\n"); -grmmE]/
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Qn.dL@W
lastExecuteTime=now; &1yJrj9y
executeUpdate(); ^4+NPk
} kN
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else{ lZL+j6Q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1W{ oj
} J8p; 1-C"
} 5WJ ~%"O
} ndzADVP
//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 a1y<Y`SC9
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类写好了,下面是在JSP中如下调用。 3qf#NJN}
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<% _<#92v!F
CountBean cb=new CountBean(); 3*~`z9-z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); BVNJas
CountCache.add(cb); v_EgY2l(
out.print(CountCache.list.size()+"<br>"); IDT\hTPIs
CountControl c=new CountControl(); g9|OhymB
c.run(); 5L[imO M0
out.print(CountCache.list.size()+"<br>"); M,@M5o2u
%>