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: PzGWff!*n
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CountBean.java dTtSUA|V7"
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/* 2-b6gc7
* CountData.java =mGez )T5\
* uGt-l4
* Created on 2007年1月1日, 下午4:44 T>GM%^h,7-
* XUw/2"D'?
* To change this template, choose Tools | Options and locate the template under 4 OX^(
* the Source Creation and Management node. Right-click the template and choose _
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* Open. You can then make changes to the template in the Source Editor. # [a*rD%m
*/ |)81Lz
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package com.tot.count; s{" 2L{,$
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/** X7wKy(g
* qFNes)_r
* @author 2
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*/ 05k0n E
public class CountBean { ?rIx/>C9
private String countType; g ci
int countId; ]_f<kW\1*
/** Creates a new instance of CountData */ 2m[<]$
public CountBean() {} 6R5Qy]]E
public void setCountType(String countTypes){ $kKjgQS(
this.countType=countTypes; 7)k\{&+P
} km40qO@3
public void setCountId(int countIds){ XrPfotj1
this.countId=countIds; F>cv<l
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} @K]|K]cby
public String getCountType(){ ]fD}
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return countType; 8*fv'
} HKr
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public int getCountId(){ Z<4AL\l 98
return countId; _l]fkk[T
} e$pV%5=
} hzRYec(
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CountCache.java * H9 8Du
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/* :h V7>
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* CountCache.java S@Hf
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* )Beiu*
* Created on 2007年1月1日, 下午5:01 ?rup/4|
* 3&/Ixm:
* To change this template, choose Tools | Options and locate the template under Bw{I;rW{2
* the Source Creation and Management node. Right-click the template and choose -GgA&dh
* Open. You can then make changes to the template in the Source Editor. S+2(f> Z
*/ h*Pc=/p
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package com.tot.count; ,iq4Iw
import java.util.*; #V}IvQl|
/** Ki~1qu:
* yOg+iFTr
* @author O#u=c1
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*/ I9Fr5p-%O
public class CountCache { 9k~8
public static LinkedList list=new LinkedList(); ~!3r&(
/** Creates a new instance of CountCache */ PzR[KUK
public CountCache() {} 9$m|'$p3sG
public static void add(CountBean cb){ o+9j?|M
if(cb!=null){ xRsWI!d+|
list.add(cb); 6u}</>}
} r)6M!_]AW
} Z`BK/:vo3H
} %!L9)(}"
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CountControl.java I0RvnMw
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/* ^KE%C;u
* CountThread.java +t:0SRSt
* (@}!0[[^
* Created on 2007年1月1日, 下午4:57 {91nL'-'
* kE(mVyLQ
* To change this template, choose Tools | Options and locate the template under Pco'l#:
* the Source Creation and Management node. Right-click the template and choose v 6Vcjm
* Open. You can then make changes to the template in the Source Editor. v]c6R-U
*/ $lut[o74
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package com.tot.count; LYg-
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import tot.db.DBUtils; zNuJj L
import java.sql.*; t!\tF[9e
/** XF_pN[}
* C{XmVc.
* @author f>Jr|#k
*/ K!]/(V(}
public class CountControl{ *r% c
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0,8okAH
/** Creates a new instance of CountThread */ |id
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public CountControl() {} wg]LVW}
public synchronized void executeUpdate(){ d&s9t;@=
Connection conn=null; O5t[
PreparedStatement ps=null; O s.4)
try{
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conn = DBUtils.getConnection(); 'oC)
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conn.setAutoCommit(false); _H=Uwi_g
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @k/NY*+
for(int i=0;i<CountCache.list.size();i++){ g
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CountBean cb=(CountBean)CountCache.list.getFirst(); U~l$\c
CountCache.list.removeFirst(); BIWWMg
ps.setInt(1, cb.getCountId()); P_p<`sC9
ps.executeUpdate();⑴ 8&Y^""#e)
//ps.addBatch();⑵ M+9 gL3W
} #`X?=/q
//int [] counts = ps.executeBatch();⑶ )Iq <+IJ
conn.commit(); :Qf '2.h)
}catch(Exception e){ f.`*Qg L
e.printStackTrace(); QW~1%`
} finally{ V}NbuvDB@
try{ 'anG:=
if(ps!=null) { lR6x3C
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ps.clearParameters(); kd$D 3S^{
ps.close(); az|N-?u
ps=null; 5j-YM
} y
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}catch(SQLException e){} \A6B,|@
DBUtils.closeConnection(conn); |WdPE@P
} 3J438M.ka
} B i<Q=x'Z;
public long getLast(){ hzbw>g+
return lastExecuteTime; Wh2tNyS
} A:9?ZI/X
public void run(){ '1)$'
long now = System.currentTimeMillis(); Eue~Y+K*b
if ((now - lastExecuteTime) > executeSep) { Z} r*K%
//System.out.print("lastExecuteTime:"+lastExecuteTime); 2oRg 2R}
//System.out.print(" now:"+now+"\n"); B\:%ufd
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); M6-&R=78K
lastExecuteTime=now; x`IEU*z#
executeUpdate(); %O;bAC_M
} n`&U~s8w
else{ x6ARzH\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); U\<?z Dw
} 7y@Pa&^8
} B=A [ymm
} )$bS}.
//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 do+.aOC
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类写好了,下面是在JSP中如下调用。 n%s]30Xs
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<%
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CountBean cb=new CountBean(); (<oyN7NT
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); cFnDmtI:
CountCache.add(cb); l.bYE/F0&
out.print(CountCache.list.size()+"<br>"); pWsDzb6?%
CountControl c=new CountControl(); Gvqxi|
c.run(); T+K):ug
out.print(CountCache.list.size()+"<br>"); P{+T<bk|
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