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: =3PZGdWD
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CountBean.java nfh<3v|kvR
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/* h6?o)Q>N
* CountData.java pZ]&M@Ijp
* <)
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* Created on 2007年1月1日, 下午4:44 5=V 29
* %qEp{itq
* To change this template, choose Tools | Options and locate the template under r{f$n
* the Source Creation and Management node. Right-click the template and choose 1Se2@WR'
* Open. You can then make changes to the template in the Source Editor. (:R5"|]@<x
*/ Pm QeO*f+
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package com.tot.count; 4{G>T
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/** =i6k[ rg
* OS1f}<
* @author _-2;!L#/
*/ j+e
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public class CountBean { /T2 v`Li
private String countType; ExF6y#Y G<
int countId; 8:2Vib$
/** Creates a new instance of CountData */ uX6p^KNm5
public CountBean() {} *VUJ);7k
public void setCountType(String countTypes){ JW"`i
this.countType=countTypes; HY;kV6g{P
} /J9Or{#r
public void setCountId(int countIds){ {REGoe=W%
this.countId=countIds; >h.HW
} kOC0d,
public String getCountType(){ -j1]H"-
return countType; &da:{
} 7>F [7_
public int getCountId(){ .3#Xjhebvu
return countId; ) )t]5Ys%;
} %'VzN3Q5V
} ^1<i7u
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CountCache.java ?Ss~!38
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/* 5BK3ix*L
* CountCache.java Cxe(iwa.
* a'd=szt
* Created on 2007年1月1日, 下午5:01 iiWpmE<,
* Tl#2w=
* To change this template, choose Tools | Options and locate the template under 6PC?*^v
* the Source Creation and Management node. Right-click the template and choose y1[@4TY]
* Open. You can then make changes to the template in the Source Editor. S,Q(,e^&
*/ %*RZxR):
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package com.tot.count; n/e ,jw
import java.util.*; $GHi9aj_P
/** dp4vybJ
* /%)(Uz
* @author ?}= $zN
*/ ~_IQ:]k
public class CountCache { 1=e(g#Ajn\
public static LinkedList list=new LinkedList(); lXEnm-_
/** Creates a new instance of CountCache */ ; P$ _:-C
public CountCache() {} qn'TIE.
public static void add(CountBean cb){ ab#z&jg!
if(cb!=null){ BB_(!omq[
list.add(cb); jy_4W!4a
} C0/G1\
} X":2o|R
} d=
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CountControl.java s3'kzwX
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/* =#A/d`2
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* CountThread.java `b%^_@Fb
* %a:T9v
* Created on 2007年1月1日, 下午4:57 87m`K Str7
* 8VuLL<\|
* To change this template, choose Tools | Options and locate the template under 0k4XVd+Nv
* the Source Creation and Management node. Right-click the template and choose [k&7h,
* Open. You can then make changes to the template in the Source Editor. IRTWmT
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*/ I3}]MAE
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package com.tot.count; =kCiJ8q|
import tot.db.DBUtils; m\E=I5*/
import java.sql.*; `cIeqp
/** E,cQ9}/
* o 9(x\g
* @author j8]M}Q$
*/ O^ 5C
public class CountControl{ ;jO+<~YP!
private static long lastExecuteTime=0;//上次更新时间 zMM~4?4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "KSdC8MS
/** Creates a new instance of CountThread */ {xOzxLB;
public CountControl() {} }SyK)W5Y
public synchronized void executeUpdate(){ i6y=3k
Connection conn=null; e@S\7Ks
PreparedStatement ps=null; q8,,[R_
try{ 3#GIZL}!x
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); qT&zg@m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); oel?w e6
for(int i=0;i<CountCache.list.size();i++){ h
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CountBean cb=(CountBean)CountCache.list.getFirst(); <q Q@OUI
CountCache.list.removeFirst(); E>O@Bv
ps.setInt(1, cb.getCountId()); ! |z!e>0
ps.executeUpdate();⑴ `LKf$cx(A
//ps.addBatch();⑵ .[1@wW&L
} *P&lAyt6
//int [] counts = ps.executeBatch();⑶ 7]i6 Gk
conn.commit(); 8dJ+Ei~M
}catch(Exception e){ T)Q_dF.N
e.printStackTrace(); "L8Hgwg
} finally{ mS49l
try{ !DV0u)k(
if(ps!=null) { $BG]is,&5
ps.clearParameters(); f zL5C2d
ps.close(); z46Sh&+
ps=null; } :gi<#-:G
} [HQ/MkP-Z
}catch(SQLException e){} }_H\75Iv
DBUtils.closeConnection(conn); %?F$3YN,
} kf#S"[/E
} NzN"_o jM
public long getLast(){ M&sQnPFH
return lastExecuteTime; NLUO{'uUW
} P{Q$(rOe
public void run(){ *i!t&s
long now = System.currentTimeMillis(); 1u(n[<WtT_
if ((now - lastExecuteTime) > executeSep) { {Z
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//System.out.print("lastExecuteTime:"+lastExecuteTime); Hw62'%
//System.out.print(" now:"+now+"\n"); k![H;}W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); y(E<MRd8V
lastExecuteTime=now; Z|)1 ftcC
executeUpdate(); {~G~=sC$
} 8Z)wot
else{ ?crK613 t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); bfpoX,:
}
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} -.L )\
} FIu^Qd
//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 a4Z e!l(
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类写好了,下面是在JSP中如下调用。 KuL+~
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<% ic l]H
CountBean cb=new CountBean(); <'BsQHI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .CNwuN\
CountCache.add(cb); aSgKh
out.print(CountCache.list.size()+"<br>"); rEbH<|
CountControl c=new CountControl(); .'h^
c.run(); 7(P4KvkI
out.print(CountCache.list.size()+"<br>"); ub+XgNO
%>