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: GBg~NkC7.
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CountBean.java 3bU(ea^e$
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/* ojva~mnFf
* CountData.java 3u,C I!
* * a ?qV
* Created on 2007年1月1日, 下午4:44 .D8|_B
* /}kG$~
* To change this template, choose Tools | Options and locate the template under (,`R >Dk
* the Source Creation and Management node. Right-click the template and choose _GbwyfA
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* Open. You can then make changes to the template in the Source Editor. d!P3<:+R[
*/ uyqu n@q
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package com.tot.count; iVSN>APe
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/** /$=<"Y7&g
* WeiDg,]e$b
* @author iwVsq_[]L
*/ G2y`yg
public class CountBean { CM`B0[B
private String countType; AY x*Ngn
int countId; @,^c?v
/** Creates a new instance of CountData */ zg>)Lq|VsT
public CountBean() {} H_nIlku
public void setCountType(String countTypes){ |L<p90
this.countType=countTypes; Jk=_8Xvr`
} k}&7!G@T
public void setCountId(int countIds){ EA``G8Vn>
this.countId=countIds; +5i~}Q!
} T0e- X
public String getCountType(){ H.)Y*zK0.
return countType; SNOML7pd
} UbDpSfub
public int getCountId(){ MUW&m2
return countId; "$krK7Z
} G%F}H/|R
} roM!%hb
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CountCache.java *Roqie
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/* 7R7e3p,K
* CountCache.java %'w?fqk
* A4{p(MS5
* Created on 2007年1月1日, 下午5:01 ^61;0
* Whl^~$+f
* To change this template, choose Tools | Options and locate the template under -{z<+(K!$
* the Source Creation and Management node. Right-click the template and choose ]|_UpP8EP
* Open. You can then make changes to the template in the Source Editor.
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*/ 7h#*djef
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package com.tot.count; eh;L])~C
import java.util.*; cd._q2
/** q:MSV{k
* GS&I6
* @author Y[0mTL4IO
*/ *X /i<
public class CountCache { yu}yON
public static LinkedList list=new LinkedList(); _={mKKoHs
/** Creates a new instance of CountCache */ =qL^#h83y
public CountCache() {} ?FV%e
public static void add(CountBean cb){ mG0_&'"YIG
if(cb!=null){ !-
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list.add(cb); {LCKt/Z>P
} 82?LZ?!PD
} % I2JS
} sBqOcy
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CountControl.java *19a\m=>oi
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/* vz1I/IdTd
* CountThread.java =En1?3?
* V{x[^+w7X~
* Created on 2007年1月1日, 下午4:57 P_75-0G
* Y4X`(\A
* To change this template, choose Tools | Options and locate the template under nQa:t. rC
* the Source Creation and Management node. Right-click the template and choose S;%k?O7v
* Open. You can then make changes to the template in the Source Editor. Uty0mc(
*/ NX:\iJD)1U
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package com.tot.count;
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import tot.db.DBUtils; K,*-Y)v2W
import java.sql.*; +V[;DOlll
/** ap"pQ[t;
* F}1._I`-
* @author &0J8ICd=
*/ uf:'"7V7
public class CountControl{ pZt>rv
private static long lastExecuteTime=0;//上次更新时间 {/>uc,8O
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 wL6G&6]</W
/** Creates a new instance of CountThread */ |_ U!i
public CountControl() {} t"e %'dFv
public synchronized void executeUpdate(){ nY\X!K65
Connection conn=null; av:%wJUl,$
PreparedStatement ps=null; 6Lg#co}9
try{ %afF%y
conn = DBUtils.getConnection(); 7-\wr^ll3
conn.setAutoCommit(false); :
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h%v qt~0
for(int i=0;i<CountCache.list.size();i++){ LW">9;n
CountBean cb=(CountBean)CountCache.list.getFirst(); u^WZsW
CountCache.list.removeFirst(); 2^:iU{
ps.setInt(1, cb.getCountId()); %e|UA-(
ps.executeUpdate();⑴ ApplWa3
//ps.addBatch();⑵ HIfi18
} 1(%6X*z
//int [] counts = ps.executeBatch();⑶ wjT#D|soI
conn.commit(); eiRVw5g
}catch(Exception e){ t? =V<Yd1
e.printStackTrace(); 7_lgo6
} finally{ 6wXy;!2
try{ rL?{+S]&^)
if(ps!=null) { n,_9Eh#WD
ps.clearParameters(); Uv=)y^H~*A
ps.close(); */$] kE
ps=null; MiF(
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} w]N;HlU
}catch(SQLException e){} ]+tO
DBUtils.closeConnection(conn); j)juvat
} wOrj-Smx
} l-Dg m
public long getLast(){ I7t}$S6
return lastExecuteTime; -OKXfN]
} N%u4uLP5k
public void run(){ .v9i|E=<~
long now = System.currentTimeMillis(); C/ ]Bx
if ((now - lastExecuteTime) > executeSep) { %%h.`p1
//System.out.print("lastExecuteTime:"+lastExecuteTime); Z 8GIZ
//System.out.print(" now:"+now+"\n"); %z"$?Iv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RL/5o"
lastExecuteTime=now; $%ww$3
executeUpdate(); WW7E*kc
} <\d2)Iv
else{ Q2Uk0:M
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^nQJo"g\
} VjZb\
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} ?3v-ppw%
} >Tn[CgH]7
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 6QP T
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类写好了,下面是在JSP中如下调用。 UyF;sw
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<% 4~WSIR-
CountBean cb=new CountBean(); 1Eryw~,,9i
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )k `+9}OO
CountCache.add(cb); A!$sOp
out.print(CountCache.list.size()+"<br>"); bPl'?3
CountControl c=new CountControl(); *_ajb:
c.run(); u =(.}
out.print(CountCache.list.size()+"<br>"); SF[Z]|0gs
%>