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: =ci5&B?
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CountBean.java O+o%C*`K
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/* zkMO3w>
* CountData.java qp_ `Fj:
* /GSI.tO
* Created on 2007年1月1日, 下午4:44 JdYF&~
* PKM$*_LcGI
* To change this template, choose Tools | Options and locate the template under pnA]@FW
* the Source Creation and Management node. Right-click the template and choose WmVw>.]@~
* Open. You can then make changes to the template in the Source Editor. MqBATW.pmJ
*/ 0^lL,rC
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package com.tot.count; 8`~3MsE"
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/** vlN. OQ
* 4e#K.HU_
* @author rU^ghF
*/ cf!k
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public class CountBean { Cm}UWX
private String countType; &CmkNm_B
int countId; GN;XB b]w
/** Creates a new instance of CountData */ =i5:*J
public CountBean() {} UuqnL{
public void setCountType(String countTypes){ 8kc'|F\
this.countType=countTypes; .x$T al
} /~rO2]rZ@
public void setCountId(int countIds){ [pWDhY
this.countId=countIds; l/UG+7
} e(\S,@VN2
public String getCountType(){ 8'xnhV
return countType; ,0~
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} 8Bt-
public int getCountId(){ fh)`kZDk
return countId; n03SXaU~V
} Mh.eAM8 _
} #DRtMrfat
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CountCache.java WblV`"~e
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/* 'C>S yU
* CountCache.java i8) :0
* D&m"~wI
* Created on 2007年1月1日, 下午5:01 >(ww6vk2
* +}0*_VW
* To change this template, choose Tools | Options and locate the template under eC`f8=V
* the Source Creation and Management node. Right-click the template and choose Jc?ssm\%
* Open. You can then make changes to the template in the Source Editor. nW%=k!''
*/ p33GKg0i+(
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package com.tot.count; }R5&[hxh4t
import java.util.*; x,c68Q)g
/** `6sQlCOnF
* %R"/`N9R,
* @author yaYt/?|
*/ >`|uc
public class CountCache { Iw|[*Nu-
public static LinkedList list=new LinkedList(); GO3YXO33
/** Creates a new instance of CountCache */ *-LU'yM6Yh
public CountCache() {} 'htA! KHF
public static void add(CountBean cb){ '^(v8lCu
if(cb!=null){ <~X6D?
list.add(cb); +<WT$ddK=5
} KR(ftG'
} d>98 E9
} BF[?* b
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CountControl.java ~%K(ou=2
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/* #=#$b _6*
* CountThread.java 4H?Ma|,
* CPeK0(7Zh
* Created on 2007年1月1日, 下午4:57 I3$vw7}5Y
* WA\f`SRF
* To change this template, choose Tools | Options and locate the template under +i!M[
* the Source Creation and Management node. Right-click the template and choose B[|/wHMsT}
* Open. You can then make changes to the template in the Source Editor. $K fk=@
*/ uWj-tzu
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package com.tot.count; F_ Cz
import tot.db.DBUtils; _-\{kJ
import java.sql.*; &LQab>{*K
/** T2; 9
* q.F1Jj
* @author B"zg85
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*/ 3 v$4LY
public class CountControl{ #7T ={mh
private static long lastExecuteTime=0;//上次更新时间 J5IJy3d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u.Yb#?
/** Creates a new instance of CountThread */ X*"O'XCA
public CountControl() {} bd*(]S9d
public synchronized void executeUpdate(){ L/LNX{|
Connection conn=null;
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PreparedStatement ps=null;
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try{
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conn = DBUtils.getConnection(); 9cj-v}5j
conn.setAutoCommit(false); \^LR5S&
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F|Ihq^q
for(int i=0;i<CountCache.list.size();i++){ HZ=yfJs nc
CountBean cb=(CountBean)CountCache.list.getFirst(); g|_*(=Q
CountCache.list.removeFirst(); ?R:Hj=.
ps.setInt(1, cb.getCountId()); ve^MqW&S
ps.executeUpdate();⑴ EC#10.
//ps.addBatch();⑵ *~^^A9C8
} =V
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//int [] counts = ps.executeBatch();⑶ kxwm08/|f
conn.commit(); 97dI4t<
}catch(Exception e){ YDD]n*&
e.printStackTrace(); ADz|Y~V!
} finally{ +[[gU;U"v
try{ hzo,.hS's
if(ps!=null) { ,peE'
ps.clearParameters(); Bys|i 0tb-
ps.close(); p'} %pAY
ps=null; 4344PBj
} @cGql=t
}catch(SQLException e){} bM3e7olWS
DBUtils.closeConnection(conn); AR3=G>hO,
} L"/ato
} D9C; JD
public long getLast(){ CnYX\^Ow
return lastExecuteTime; k>hZ
} k8V0-.UL}
public void run(){ Wh_c<E}&
long now = System.currentTimeMillis(); CI'5JOqP
if ((now - lastExecuteTime) > executeSep) { E/;YhFb[
//System.out.print("lastExecuteTime:"+lastExecuteTime); \c}r6xOr
//System.out.print(" now:"+now+"\n"); j=S"KVp9NF
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K$]B"
s
lastExecuteTime=now;
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executeUpdate(); { rn~D5R
} 3R.cj
else{ fBOG#-a}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P'~3WL4MKs
} {HnOUc\4
} o]U==
} ]NsaFDi\
//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 rRel\8
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类写好了,下面是在JSP中如下调用。 ^]gl#&"D
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<% pBkPn+@
CountBean cb=new CountBean(); '~J6mojE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3)\qts5
CountCache.add(cb); _4Pi>
out.print(CountCache.list.size()+"<br>"); Hefqzu
CountControl c=new CountControl(); {!h[@f4
c.run(); >,vuC4v-
out.print(CountCache.list.size()+"<br>"); {piS3xBi
%>