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: .( h$@|Y
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CountBean.java Hg`{9v
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/* !XG&=Rd?
* CountData.java pxxFm~"d
* qDM[7q3.
* Created on 2007年1月1日, 下午4:44 +q/h:q.TV
* Qu,k
* To change this template, choose Tools | Options and locate the template under jw[BtRW
* the Source Creation and Management node. Right-click the template and choose XKX,7
* Open. You can then make changes to the template in the Source Editor. 4Aew
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*/ n^\;*1%$c@
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package com.tot.count; 38rZ`O*D
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/** ZZU 8B?)
* #(
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* @author =&pN8PEn\
*/ &fW=5'
public class CountBean { yCIgxPv|7
private String countType; <j\;>3Q
int countId; .4<U*Xkt
/** Creates a new instance of CountData */ WrNgV@P
public CountBean() {} 5%+}rSn7
public void setCountType(String countTypes){ 1=Zw=ufqV
this.countType=countTypes; \Byk`}
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} B bw1k
public void setCountId(int countIds){ 0 l:pWc
this.countId=countIds; huJq#5?
} 3DAGW"F
public String getCountType(){ 6KCmswvE
return countType; `Kw"XGT
} 4E-A@FR
public int getCountId(){ *ZR@z80i
return countId; AaYrVf 9!
} YC&jKx .>
} g0j4<\F2\
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CountCache.java ` G=L07
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/* (oitCIV
* CountCache.java G>,nZ/,A{
* W)!{U(X
* Created on 2007年1月1日, 下午5:01 5@D7/$bLp
* $xtE+EV.p
* To change this template, choose Tools | Options and locate the template under yVI;s|jG
* the Source Creation and Management node. Right-click the template and choose tOg
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* Open. You can then make changes to the template in the Source Editor. [A9,!YY
*/ [Z#.]gb
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package com.tot.count; 9G&l qfX:
import java.util.*; y3nm!tjyM
/** C^" Hj
* I?Jii8|W9
* @author |SP.S 0.y
*/ tnF9Vj[#%_
public class CountCache { mvA xx`jc
public static LinkedList list=new LinkedList(); *:T>~ilF
/** Creates a new instance of CountCache */ s`iNbW="
public CountCache() {} <W51 oO
public static void add(CountBean cb){ ^q&wITGI
if(cb!=null){ )fMX!#KP
list.add(cb); \U*-w:+@
} `Kc %S^C'
} gQh Ccv
} reM
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CountControl.java Uaj`
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/* +%#MrNM'
* CountThread.java \8*,&ak%
* ,AbKxT
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* Created on 2007年1月1日, 下午4:57 :@>br+S
* Dd#
SUQ
* To change this template, choose Tools | Options and locate the template under JXY!c\,
* the Source Creation and Management node. Right-click the template and choose }C{}oLz
* Open. You can then make changes to the template in the Source Editor. Q)6wkY+!
*/ }1]!#yMfq
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package com.tot.count; oA;jy
import tot.db.DBUtils; H@2v<e@
import java.sql.*; V1`5D7Z
/** #HM\a
* I4<{R
* @author Jh&~/ntmm_
*/ L_~I~
public class CountControl{ Vr-3M+l=O
private static long lastExecuteTime=0;//上次更新时间 L`\`NNQC
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 *mQDS.'AB@
/** Creates a new instance of CountThread */ RC8)f8n
public CountControl() {} ^KZAYB9C
public synchronized void executeUpdate(){ *)NR$9lGv
Connection conn=null; B)DC,+@$
PreparedStatement ps=null; <Id1:
try{ F/h :&B:;
conn = DBUtils.getConnection(); )pS_+ZF
conn.setAutoCommit(false); V^ fGRA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {FJX
for(int i=0;i<CountCache.list.size();i++){ M8?#%x6;N
CountBean cb=(CountBean)CountCache.list.getFirst(); urrO1
CountCache.list.removeFirst(); u_4:#~b
ps.setInt(1, cb.getCountId()); ?b@q5Y
ps.executeUpdate();⑴ *H%0Gsk
//ps.addBatch();⑵ 6>=-/)p}
} $
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//int [] counts = ps.executeBatch();⑶ T^'*_*m
conn.commit();
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}catch(Exception e){ FI`nRFq)C
e.printStackTrace(); =MJ-s;raq
} finally{ T+K` ^xv_L
try{ %;<k(5bhGJ
if(ps!=null) { J\xz^%p
ps.clearParameters(); ycrh5*g
ps.close(); )'j_D<
ps=null; )l!J$X+R
} =wIdC3Ph
}catch(SQLException e){} yp[<9%Fi
DBUtils.closeConnection(conn); rysP)e
} )e|$K=
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} k+WO &g*|
public long getLast(){ 7cUR.PI#Q
return lastExecuteTime; %UUp=I
} Ok}{jwJ%W;
public void run(){ o\@ A2r3
long now = System.currentTimeMillis(); agU%z:M{
if ((now - lastExecuteTime) > executeSep) { ,#E3,bu6_4
//System.out.print("lastExecuteTime:"+lastExecuteTime); n&0mz1rw
//System.out.print(" now:"+now+"\n"); T.Pklty
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); L9{mYA]q
lastExecuteTime=now; `qf\3JT\
executeUpdate(); ;}n9yci#
} u#41osUVW>
else{ Uh3wj|0
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B_SZ?o
} @tr&R==([
} |TB@@ 2Ky&
} lBlSNDs
//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 |t4Gz1"q=8
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类写好了,下面是在JSP中如下调用。 .Bb$j=
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<% i"%JFj_G
CountBean cb=new CountBean(); uQ[vgNe*m
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,zAK3d&hj
CountCache.add(cb); bU;}!iVc]
out.print(CountCache.list.size()+"<br>"); Mvy6"Q:
CountControl c=new CountControl(); LN@E\wRw{r
c.run(); aW0u8Dz
out.print(CountCache.list.size()+"<br>"); RNv{n
mf
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