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: zITxJx
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CountBean.java im)r4={
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/* /3sX>Rj
* CountData.java XVo+ <&
* -Oz! GX
* Created on 2007年1月1日, 下午4:44 {F\P3-ub
* WyM2h
* To change this template, choose Tools | Options and locate the template under _^ n>kLd$
* the Source Creation and Management node. Right-click the template and choose Z>X]'q03
* Open. You can then make changes to the template in the Source Editor. |942#rM
*/ bTAY5\wB
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package com.tot.count; w?M"`O(
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/** (wxi!
* ~,8#\]xR
* @author k$DRX)e
*/ 7*WO9R/
public class CountBean { *1:kIi7_
private String countType; $GhL-sqm
int countId; *&+zI$u(
/** Creates a new instance of CountData */ MhD=\Lpj\
public CountBean() {} DPmY_[OAE
public void setCountType(String countTypes){ "Wb KhE
this.countType=countTypes; uFlf#t
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} OI6m>XH?
public void setCountId(int countIds){ nhZ/^`Y<
this.countId=countIds; =`CK`x
} m?8o\|i,
public String getCountType(){ *;F<Q!i&v
return countType; CEzdH!nP
} G$CSZrP.
public int getCountId(){ \-[ >bsg
return countId; !u4eI0?R?
} t.bM]QU!1
} "W9z>ezp
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CountCache.java i!(5y>I_
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/*
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* CountCache.java 4((p?jbC
* Tn\{*A
* Created on 2007年1月1日, 下午5:01 ;Cty"H,
* {CTJX2&
* To change this template, choose Tools | Options and locate the template under ^bdXzjf
* the Source Creation and Management node. Right-click the template and choose i`iR7UmHeR
* Open. You can then make changes to the template in the Source Editor. q,;wD1_wG
*/ 3e\IRF xzb
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package com.tot.count; ?T|0"|\"'
import java.util.*; 9gIim
/** /{I-gjovy
* E4_,EeC#
* @author cw0uLMqr`
*/ DC_k0VBn
public class CountCache { :TV`uUE
public static LinkedList list=new LinkedList(); LA/Qm/T
/** Creates a new instance of CountCache */ :vaVghN\
public CountCache() {} Wu8zK=Ve(
public static void add(CountBean cb){ fZnq5rTk"
if(cb!=null){ Jv]$@>#
list.add(cb); wqzpFPk(
} ;W\?lGOs{
} (_gt!i{h
} 13Q87i5B
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CountControl.java
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/* hb}Qt Q
* CountThread.java - _%~b
* iYlkc
* Created on 2007年1月1日, 下午4:57 :<5jlpV(
* <HpUP!q8v
* To change this template, choose Tools | Options and locate the template under Ufor>
* the Source Creation and Management node. Right-click the template and choose t"MrrK>T
* Open. You can then make changes to the template in the Source Editor. P1Iy>%3
*/ 'Ddzlip
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package com.tot.count; q{f (T\
import tot.db.DBUtils; 'cc{sjG
import java.sql.*; Np$ue
}yr
/** GsiKL4|mj
* h1f 05
* @author HoeW6U V
*/ T;S6<J
public class CountControl{ S{{wcH$n'i
private static long lastExecuteTime=0;//上次更新时间 :1]J{,VG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1vJj?Uqc
/** Creates a new instance of CountThread */ ~K(mt0T)
public CountControl() {} g!cW`B'
public synchronized void executeUpdate(){ T&Z*=ShH
Connection conn=null; `9\^.g)
PreparedStatement ps=null; Z4gn7
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try{ WQBV~.<Yv
conn = DBUtils.getConnection(); G%K&f1q%
conn.setAutoCommit(false); xNLgcb@v>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q:vGG K^
for(int i=0;i<CountCache.list.size();i++){ wZKmU
CountBean cb=(CountBean)CountCache.list.getFirst(); .4<lw
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); W"A3$/nq^
ps.executeUpdate();⑴ 6X4r2Vq
//ps.addBatch();⑵ BD]o+96qP
} 6k{gI.SG
//int [] counts = ps.executeBatch();⑶ Pw6%,?lQ
conn.commit(); 38:5g_
}catch(Exception e){ {7_C|z:'p&
e.printStackTrace(); &78lep
} finally{ -uhVw_qq#
try{ .VohW=D3
if(ps!=null) { |M18/{
ps.clearParameters(); =hI;5KF
ps.close(); TS=U%)Ik
ps=null; ;sx4w!Y,
} 82 o|(pw
}catch(SQLException e){} sN MF(TY
DBUtils.closeConnection(conn); S?c<Lf~W
} vw-y:,5`t8
} h&~9?B
public long getLast(){ 2~V"[26t
return lastExecuteTime; \zOsq5}
} k(@W
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public void run(){ ]a[2QQ+g
long now = System.currentTimeMillis(); J\J3'u
if ((now - lastExecuteTime) > executeSep) { P=s3&NDD
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4`Jf_C
//System.out.print(" now:"+now+"\n"); J]Rh+@r.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZQ-6n1O
lastExecuteTime=now; mSO7 r F
executeUpdate(); sG^{
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} .;(a;f+{;
else{ 19%zcYTe
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); C3
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} {j4&'=C:
} JcfGe4
} ZzP&Zrm
//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 Deq@T {
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类写好了,下面是在JSP中如下调用。 _'n]rQ'
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<% G6xNR
CountBean cb=new CountBean(); b7gN|Hw5 H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ]]y,FQ,r
CountCache.add(cb); _G2)=yj]
out.print(CountCache.list.size()+"<br>"); xP27j_*m>
CountControl c=new CountControl(); $-s8tc(
c.run(); w U1[/
out.print(CountCache.list.size()+"<br>"); XK;Vu#E*^
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