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: [xqV`(vM
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CountBean.java Vuz.b.,i`
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/* v~mVf.j1
* CountData.java ?+]=|hN
* ZDW9H6ux
* Created on 2007年1月1日, 下午4:44 i<Z%
* B|m)V9A%-
* To change this template, choose Tools | Options and locate the template under OjGI
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* the Source Creation and Management node. Right-click the template and choose :8`A
* Open. You can then make changes to the template in the Source Editor.
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*/ xO|r<R7d7
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package com.tot.count; W %*#rcdq
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/** g<Z :`00|
* R/=rNUe
* @author Ll]5u~
*/ s!IIvF
public class CountBean { 3-/|G-4k7
private String countType; ]y@A=nR
int countId; Da-Lf2qT9
/** Creates a new instance of CountData */ fl-J:`zyyZ
public CountBean() {} C5~~$7k0
public void setCountType(String countTypes){ ;FqmZjm
this.countType=countTypes; +[G9PP6
} O=jLZ2os
public void setCountId(int countIds){ zM0}(5$m
this.countId=countIds; sT?{
} W\l&wR
public String getCountType(){ <{#_;7h"
return countType; QP\9#D~
} sa'1hX^@
public int getCountId(){ /"X_{3dq?
return countId; x0# Bc7y
} 5_(\Cd<#
} 6l\5J6x
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CountCache.java Z!g6uV+.5
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/* {T8;-H0H
* CountCache.java SW9
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* S70#_{
* Created on 2007年1月1日, 下午5:01 [QnN1k
* "W(D0oy
* To change this template, choose Tools | Options and locate the template under }PI:O%N;
* the Source Creation and Management node. Right-click the template and choose I0mp [6
* Open. You can then make changes to the template in the Source Editor. W]po RTJ:
*/ d27q,2f!
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package com.tot.count; *'?ZG/ (
import java.util.*; 'maX
/** s, Gl{
* ek&~A0k_o
* @author |.@!CqJ
*/ T1C_L?L
public class CountCache { :Q`Of}#
public static LinkedList list=new LinkedList(); Q+Bl1xl
/** Creates a new instance of CountCache */ E
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public CountCache() {} JSB+g;
public static void add(CountBean cb){ boojq{cvYA
if(cb!=null){ 3H,x4L5j
list.add(cb); `Abd=1nH
} 5M>h[Q"R
} j-9)Sijj{
} -@XSDfy7S
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CountControl.java _%CM<z
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/* nL?P/ \
* CountThread.java Gi)Vr\Q.
* "lt <$.
* Created on 2007年1月1日, 下午4:57 |"}rdOV)
* }R;}d(C`
* To change this template, choose Tools | Options and locate the template under 1WtE ]
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* the Source Creation and Management node. Right-click the template and choose "w?0f["
* Open. You can then make changes to the template in the Source Editor. tl_3 %$s
*/ Z' i@;^=A
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package com.tot.count; c+ZOC8R
import tot.db.DBUtils; s",Ea*
import java.sql.*; Fn5BWV
/** ^=x /:0
* ;n't:yQW
* @author d}O\:\}y
*/ ^t3>Z|DiB^
public class CountControl{ /Qst :q
private static long lastExecuteTime=0;//上次更新时间 \lg
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7I
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/** Creates a new instance of CountThread */ 1KUjb@"
public CountControl() {} |pHlBzHj
public synchronized void executeUpdate(){ ir6aV|ea!
Connection conn=null; ?q`i
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PreparedStatement ps=null; G/JGb2I/7|
try{ uBts?02
conn = DBUtils.getConnection(); 7> f2P!:
conn.setAutoCommit(false); Milp"L?B%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~B[e*|d
for(int i=0;i<CountCache.list.size();i++){ 6c!F%xU}
CountBean cb=(CountBean)CountCache.list.getFirst(); )M<+?R$];
CountCache.list.removeFirst(); mP*$wE9b,:
ps.setInt(1, cb.getCountId()); y`j_]qvt
ps.executeUpdate();⑴ e\X[\ve
//ps.addBatch();⑵ /rpr_Xw}
} ^1 ){
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//int [] counts = ps.executeBatch();⑶ n>)aw4
conn.commit(); &vmk!wAs
}catch(Exception e){ ,Mw93Kp
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e.printStackTrace(); WdOxwsq"
} finally{ V<5. 4{[G
try{ C
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if(ps!=null) { $*eYiz3Ue
ps.clearParameters(); [CEV&B
ps.close(); 80Y%C-Y:
ps=null; qoZi1,i'
} s O#cJAfuu
}catch(SQLException e){} bqH
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DBUtils.closeConnection(conn); d3z nb@7
} P
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} At@0G\^
public long getLast(){ pmP~1=3
return lastExecuteTime; _Yo)m|RaB
} 0y$VPgsKf
public void run(){ Y[e.1\d'
long now = System.currentTimeMillis(); Y*@7/2,
if ((now - lastExecuteTime) > executeSep) { gE #|eiu
//System.out.print("lastExecuteTime:"+lastExecuteTime); #r9\.NA!
//System.out.print(" now:"+now+"\n"); z#!<[**&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Aq(cgTNW
lastExecuteTime=now; I'IFBVhaYn
executeUpdate(); GDCp@%xW
} ga|<S@u?}
else{ `.;U)}Tn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K3vZ42n
} =p@2[Uo
} n`^jNXE
} ,JI] Eij^
//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 #8XmOJ"W3k
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类写好了,下面是在JSP中如下调用。 (P?|Bk[
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<% a)W|gx6Y
CountBean cb=new CountBean(); t8Pf~v
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~hq\XQX
CountCache.add(cb); *
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out.print(CountCache.list.size()+"<br>"); f-#:3k*7S
CountControl c=new CountControl(); PI L)(%X
c.run(); W'9{2h6u(
out.print(CountCache.list.size()+"<br>"); TAh'u|{u2
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