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: ?cU,%<r
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CountBean.java Bf{u:TCK
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/* q lc@$
* CountData.java !eX0Q 2
* CPz<iU
* Created on 2007年1月1日, 下午4:44 ?ZF):}rvZ
* Ailq,c
* To change this template, choose Tools | Options and locate the template under Qqm?%7A1
* the Source Creation and Management node. Right-click the template and choose \"lz,bT
* Open. You can then make changes to the template in the Source Editor. I G1];vX
*/ %rwvY`\
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package com.tot.count; F};R
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/** #QNN;&L]R
* [WwoGg*)mn
* @author 'l*X?ccKy
*/ _w^,j"
public class CountBean { %>Kba M1b
private String countType; VjQ&A#
int countId; H 0l1=y
/** Creates a new instance of CountData */ gV_v5sk
public CountBean() {} q*I*B1p[m
public void setCountType(String countTypes){ c1YDln
this.countType=countTypes; "@V yc6L
} [F-R*}&x
public void setCountId(int countIds){ xyL"U*
this.countId=countIds; Z.VKG1e}
} T#!>mL|9|
public String getCountType(){ d |17G
return countType; <PLAAh8
} Xu$>$D#a
public int getCountId(){ b:==:d:0s
return countId; z.Cj%N
} 0 QTI;3
} &Ok1j0~~
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CountCache.java W+h2 rv
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/* mxNd_{n
* CountCache.java h}Otz "
* `/O`%6,f1!
* Created on 2007年1月1日, 下午5:01 R%UTYRLUn
* 0jTReY-W
* To change this template, choose Tools | Options and locate the template under z8\YMr6o
* the Source Creation and Management node. Right-click the template and choose q/O2E<=w*c
* Open. You can then make changes to the template in the Source Editor. M2Q,&>M
*/ Hw \of
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package com.tot.count; e]4$H.dP
import java.util.*; $*q|}Tvl#
/** :ld~9
* "U\RN
* @author UtQj<18<
*/ <)7aNW.
public class CountCache { qTJhYxm
public static LinkedList list=new LinkedList(); (&}[2pb!
/** Creates a new instance of CountCache */ )Q 2IYCj{
public CountCache() {} gN/<g8
public static void add(CountBean cb){ C;W@OS-;
if(cb!=null){ >|taU8^|G}
list.add(cb); JFT$1^n
} z; GQnAG@
} wGyVmC
} __=53]jGE
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CountControl.java Ht[$s4 0P
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/* #Y7jNrxE
* CountThread.java '1mk;%
* V}y]<
* Created on 2007年1月1日, 下午4:57 sT^R0Q'>
* u/=hueR<^
* To change this template, choose Tools | Options and locate the template under g p:0 Y
* the Source Creation and Management node. Right-click the template and choose eF+F"|1h
* Open. You can then make changes to the template in the Source Editor. X1#Ar)
*/ s~M$Wo8
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package com.tot.count; VYG@_fd!x
import tot.db.DBUtils; <6UXk[y
import java.sql.*; PUR,r%K`
/** uu6 JZp
* |
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* @author jQ{ @ol}n
*/ BUXE
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public class CountControl{ q T6y&
private static long lastExecuteTime=0;//上次更新时间 ZJDV'mC}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 q`xc h[H
/** Creates a new instance of CountThread */ v>8.TE~2
public CountControl() {} ^4`aONydl
public synchronized void executeUpdate(){ 0qS/>u*
Connection conn=null; sOhn@*X
PreparedStatement ps=null; Qs1CK;+zU
try{ u
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conn = DBUtils.getConnection(); <K CI@
conn.setAutoCommit(false); .W{CJh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P@v"aa\@2)
for(int i=0;i<CountCache.list.size();i++){ 5wue2/gl
CountBean cb=(CountBean)CountCache.list.getFirst(); 78l);/E{v
CountCache.list.removeFirst(); $1.-m{Bd
ps.setInt(1, cb.getCountId()); HV a9b;
ps.executeUpdate();⑴ V0;"Qa@q
//ps.addBatch();⑵ 1jKpLTSs
} ^lp=4C9
//int [] counts = ps.executeBatch();⑶ aE~T!h
conn.commit(); N<Sl88+U
}catch(Exception e){ ~.T|n =
e.printStackTrace(); w)7y{ya$
} finally{ ;W-
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try{ x?L0R{?WW
if(ps!=null) { gmVN(K}SR5
ps.clearParameters(); \5a.JfF
ps.close(); /43l}6I
ps=null; gX"-3w
} \c2x
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}catch(SQLException e){} #D9.A7fCc5
DBUtils.closeConnection(conn); i^DMnvV.
} ,C,nNaW
} NK0'\~7&
public long getLast(){ h$8h@2%
return lastExecuteTime; 6{6hz8
} 'V]C.`9c
public void run(){ (WHgB0{
long now = System.currentTimeMillis(); OlT8pG5Oa
if ((now - lastExecuteTime) > executeSep) { L\#YFf
//System.out.print("lastExecuteTime:"+lastExecuteTime); >6S7#)0T
//System.out.print(" now:"+now+"\n"); eha|cAq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +u|"q+p
lastExecuteTime=now; Ar<5UnT
executeUpdate(); L6h<B
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} g+B7~Z5,
else{ ]N 9N][n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F0!Z1S0g
} 9"#C%~=+
} !q&Td
} ,:mL\ZED
//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 |y^=(|eM
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类写好了,下面是在JSP中如下调用。 b-ss^UL
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<%
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CountBean cb=new CountBean(); ."wF86jW|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !h#ZbErW
CountCache.add(cb); %SC Jmn2
out.print(CountCache.list.size()+"<br>"); tK;xW
CountControl c=new CountControl(); SZH`-xb!+5
c.run(); /B t!xSI
out.print(CountCache.list.size()+"<br>");
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