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: 6h+/C]4
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CountBean.java JH)&Ca>S
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/* _R5^4 -Qe
* CountData.java Wc,8<Y'
* 6_XX[.%
* Created on 2007年1月1日, 下午4:44 T7W+K7kbI
* U4N
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* To change this template, choose Tools | Options and locate the template under (O`=$e
* the Source Creation and Management node. Right-click the template and choose +IS$Un
* Open. You can then make changes to the template in the Source Editor. (Nik(Oyj"
*/ -\NB*|9m|
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package com.tot.count; { @-Q1
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/** ww\/$ |
* "{V,(w8Dt
* @author p{-1%jQ}]
*/ aY {.
public class CountBean { V 9<[v?.\
private String countType; 7#g C(&\A
int countId; yY"%6k,ZB
/** Creates a new instance of CountData */ #;mZ3[+i5
public CountBean() {} Nc"h8p?
public void setCountType(String countTypes){ ZVGw@3
this.countType=countTypes; $%t{O[(
} _K;rM7
public void setCountId(int countIds){ zP9 HYS
this.countId=countIds; hM8G"b
} qQ1m5_OD`z
public String getCountType(){ uq 6T|Zm
return countType; yTDoS|B+)
} "(C}Dn#
public int getCountId(){ e<C5}#wt
return countId; n[iil$VKh
} vfy-;R(
} oOUVU}H
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CountCache.java yRgo1o w]
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/* g|+G(~=e|
* CountCache.java 17
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* ]&r/H17
* Created on 2007年1月1日, 下午5:01 Yd<~]aXM
* 9J%>2AA
* To change this template, choose Tools | Options and locate the template under uq%RZF
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* the Source Creation and Management node. Right-click the template and choose $ o t"Du
* Open. You can then make changes to the template in the Source Editor. "RShsJZMH
*/ tNUcmiY
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package com.tot.count; T\WNT#My
import java.util.*; #Se
/** /=3g-$o{`
* M,#t7~t
* @author q7)$WXe2LM
*/ _ssHRbE
public class CountCache { '<}7bw}+c
public static LinkedList list=new LinkedList(); !^LvNW\|
/** Creates a new instance of CountCache */ L,D!T&B
public CountCache() {} cX=` Tl
public static void add(CountBean cb){ C>03P.s4c
if(cb!=null){ C>MoR 3]
list.add(cb); 22*t%{(
} I|LS_m
} BF_k~
} JPpYT~4
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CountControl.java UwM}!K7)G
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/* b%_QL3m6
* CountThread.java Q3/q%#q>
* 1a)_Lko
* Created on 2007年1月1日, 下午4:57 siG?Sd_2
* B{K'"uC
* To change this template, choose Tools | Options and locate the template under g9
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* the Source Creation and Management node. Right-click the template and choose f,-|"_5;
* Open. You can then make changes to the template in the Source Editor. cPN7^*
*/ yf8UfB#a
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package com.tot.count; 1uH\Bn]p?
import tot.db.DBUtils; I|ULf
import java.sql.*; QO?ha'Sl
/** /9yiMmr5W
* $yc,D=*Isi
* @author 'qP^MdoE%~
*/ Mb9q<4
public class CountControl{ /Z% ?;
private static long lastExecuteTime=0;//上次更新时间 o|}%pc3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H@3+K$|v
/** Creates a new instance of CountThread */ #0P<#S^7
public CountControl() {} (Q4_3<G+
public synchronized void executeUpdate(){ y-@!, @e
Connection conn=null; g 764wl
PreparedStatement ps=null; HcVPJuD
try{ I{AU,
conn = DBUtils.getConnection(); jQr~@15J#
conn.setAutoCommit(false); $XI<s$P%(%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PRLV1o1#
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); $Us@fJr
CountCache.list.removeFirst(); kg61Dgu
ps.setInt(1, cb.getCountId()); ,G:4H%?
ps.executeUpdate();⑴ Pz)QOrrG~
//ps.addBatch();⑵ F*w|/- e
} .J@[v
//int [] counts = ps.executeBatch();⑶ nn
conn.commit(); EGDE4n5>I
}catch(Exception e){ C&st7.
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e.printStackTrace(); `MwQ6%lf
} finally{ $oQsh|sTI
try{ 6P~"7k
if(ps!=null) { hHg
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ps.clearParameters(); &59#$LyH`%
ps.close(); 5HIpoj;\(
ps=null; b
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} 6m"
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}catch(SQLException e){} _9@?Th&_e
DBUtils.closeConnection(conn); qN0#=X
} Y1'.m5E
} I>3]4mI*a
public long getLast(){ 8k1r|s@d
return lastExecuteTime; ygW@[^g
} 'f}S,i +q
public void run(){ aK&+p#4t
long now = System.currentTimeMillis(); vedMzef[@>
if ((now - lastExecuteTime) > executeSep) { _Ry.Wth
//System.out.print("lastExecuteTime:"+lastExecuteTime); _%2Umy|
//System.out.print(" now:"+now+"\n"); pzax~Vp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <D dHP
lastExecuteTime=now; 0V#t ;`Q3
executeUpdate(); )[)]@e
} 9HE(*S
else{ G}-.xj]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4d 3Znpf
} D{4hNO
} Uaj=}p\+.p
} L@4zuzmlb
//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 4QN;o%,
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类写好了,下面是在JSP中如下调用。 0;h1LI)
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<% /hM>dkwu
CountBean cb=new CountBean(); yKB[HpU-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `I>K?
CountCache.add(cb); s4gNS
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out.print(CountCache.list.size()+"<br>"); UvZ@"El
CountControl c=new CountControl(); ;a3nH
c.run(); D,n}Qf!GYk
out.print(CountCache.list.size()+"<br>"); XeSbA
%>