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: @%cJjZ5y
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CountBean.java LA@}{hU
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/* u!`C:C'
* CountData.java ]R>k0X.V
* b~1p.J4
* Created on 2007年1月1日, 下午4:44 YL=k&QG
* gS|xicq!
* To change this template, choose Tools | Options and locate the template under E:E&Wv?r
* the Source Creation and Management node. Right-click the template and choose =L
wX+c
* Open. You can then make changes to the template in the Source Editor. `Zi #rr|)L
*/ o5$K^2^g
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package com.tot.count; a&ByV!%%+_
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/** O.}gG6u5
* tB3CX\e
* @author f}'gg
*/ }Voh5*$E`
public class CountBean { <d5vVn
private String countType; (Mm{"J3uv
int countId; A7RX2
/** Creates a new instance of CountData */ 8k`zMT
public CountBean() {} d,+n,;6Cf
public void setCountType(String countTypes){ jb![ Lp
this.countType=countTypes; dS&8R1\>1
} jRkq^}
public void setCountId(int countIds){ "=n8PNV/
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this.countId=countIds; ;Gs**BB&
} .}<B*e=y
public String getCountType(){ 9iy|=
return countType; @
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} pNJM]-D]m~
public int getCountId(){ 9cmJD5OO
return countId; +?:V\niQI
} q5W'P>
} l>(G3lIw
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CountCache.java 2*L/c-
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/* >C}RZdO~
* CountCache.java r"[T9
* nm-Y?!J
* Created on 2007年1月1日, 下午5:01 |YFD|
* G!;[If:<e
* To change this template, choose Tools | Options and locate the template under u.=;A#
* the Source Creation and Management node. Right-click the template and choose a*[\edcHU
* Open. You can then make changes to the template in the Source Editor. ed*AU,^@v
*/ X[~CLKH(
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package com.tot.count; V6{xX0'b*m
import java.util.*; =|%T E
/** w;$+7
* qU
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* @author -N(MEzAE
*/ ">9CN$]J
public class CountCache { y4L9Cxvs
public static LinkedList list=new LinkedList(); Madaxx
/** Creates a new instance of CountCache */ ksaC[G;}:
public CountCache() {} 7:<Ed"rdE
public static void add(CountBean cb){ Mv=cLG?X
if(cb!=null){
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list.add(cb); E}=,"i
} 8 vw]u_e
} gAY2|/,
} KxwLKaImI
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CountControl.java UVJ(iNK"
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/* [alXD_
* CountThread.java 0cUt"(]
* 5Z,lWp2A
* Created on 2007年1月1日, 下午4:57 /,UkT*+>!
* ~`E4E
* To change this template, choose Tools | Options and locate the template under B^?XE(.
* the Source Creation and Management node. Right-click the template and choose #+PbcL
* Open. You can then make changes to the template in the Source Editor. o{LFXNcg[
*/ EvmmQ
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package com.tot.count; Q9>]@DrAx
import tot.db.DBUtils; Y%l3SB,5L
import java.sql.*; ~Wm}M
/** :a@z53X@M
* $SVGpEw
* @author 2oG|l!C
*/ " G6jUTt
public class CountControl{ 8w[EyVHA
private static long lastExecuteTime=0;//上次更新时间 @EZONKT
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l5ds`uR#
/** Creates a new instance of CountThread */ }z+"3A|
public CountControl() {} W@dY:N}
public synchronized void executeUpdate(){ UJ$:5*S=u
Connection conn=null; odf^W
PreparedStatement ps=null; ,P@-DDJ
try{ DZ.trtK
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); Sg>0P*K@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); QJM!Wx+
for(int i=0;i<CountCache.list.size();i++){ 9 lJj/
CountBean cb=(CountBean)CountCache.list.getFirst(); ^(*O$N*#
CountCache.list.removeFirst(); Jk`)`94I
ps.setInt(1, cb.getCountId()); H`lD@q'S
ps.executeUpdate();⑴ "@w%TcA
//ps.addBatch();⑵ E}9ldM=]s
} D])YP0|}
//int [] counts = ps.executeBatch();⑶ >? eTbtP
conn.commit(); jsd]7C
}catch(Exception e){ _lv:"/3R
e.printStackTrace(); GPLt<K!<#
} finally{ '2$!thm
try{ oK:P@V6!
if(ps!=null) { %H@76NvEz
ps.clearParameters(); E2H<{Q
ps.close(); WcO,4:
ps=null; ;OU>AnWr(&
} bXwoJ2
}catch(SQLException e){} ]NV ]@*`tO
DBUtils.closeConnection(conn); zf>^2t*\
} xevP2pYG:
} 5qkuKF
public long getLast(){ dHF$T33It
return lastExecuteTime; 3,L3C9V'
} qK
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public void run(){ _JTxm>
long now = System.currentTimeMillis(); uo'31V0
if ((now - lastExecuteTime) > executeSep) { 0(/D|
//System.out.print("lastExecuteTime:"+lastExecuteTime); /NX7Vev
//System.out.print(" now:"+now+"\n"); `{lAhZ5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Guw|00w,Q$
lastExecuteTime=now; OrEuQ-,i@
executeUpdate(); k5;Vl0Ho
} KI@
else{ xf"5<PTW</
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E+ 3yN\X(
} *8.@aX3
} ]_: TrH
} kefv=n*]l
//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 N^(lUba
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类写好了,下面是在JSP中如下调用。 2, "q_d'V
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<% N46$EsO!h
CountBean cb=new CountBean(); vd7N&c9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); G h[`q7B
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CountCache.add(cb); _OU.JrqC
out.print(CountCache.list.size()+"<br>"); ;i9<y8Dha
CountControl c=new CountControl(); Vm;Qw
c.run(); j-`X_8W
out.print(CountCache.list.size()+"<br>"); ~J>gVg%66
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