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: +"|TPKas
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CountBean.java Ylgr]?Db*
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/* .B'ws/%5\
* CountData.java m/< @Qw
* lsgZ
* Created on 2007年1月1日, 下午4:44 z f>(Y7M
* o|_9%o52'
* To change this template, choose Tools | Options and locate the template under _BvGEM`o
* the Source Creation and Management node. Right-click the template and choose $bN_0s0:'
* Open. You can then make changes to the template in the Source Editor. Xo6zeLHO
*/ -U\s.FI.AR
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package com.tot.count; +6n\5+5
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/** H29vuGQjq
* k7(lwEgNG
* @author k ,ezB+
*/ Qv)DSl
public class CountBean { +
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private String countType; ME.!l6lm\
int countId; Qtt3;5m
/** Creates a new instance of CountData */ |D[LU[<C
public CountBean() {} Or55_E
public void setCountType(String countTypes){ E5a7p.
this.countType=countTypes; L[U?{
} AtqsrYj
public void setCountId(int countIds){ cE?p~fq<
this.countId=countIds;
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} ):n'B` f}z
public String getCountType(){ !LsIHDs4
return countType; L D%SLJ:
} Pj5:=d8z(
public int getCountId(){ tq L2' (=
return countId; 6H;\Jt
} mApl;D X
} ']Z%6_WF
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CountCache.java w8#ji 1gX
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/* 162Dj$
* CountCache.java &G?w*w_n
* ~
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* Created on 2007年1月1日, 下午5:01 j9BcoEl:;
* 3ik~PgGoKQ
* To change this template, choose Tools | Options and locate the template under U}l=1B
* the Source Creation and Management node. Right-click the template and choose at\$
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* Open. You can then make changes to the template in the Source Editor. urQ<r{$x0
*/ zXkq2\GHA
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package com.tot.count; <X?xr f
import java.util.*; CX;
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/** H;+98AIy`
* 48{B} j%oU
* @author 5fLp?`T
*/ n'1LNi
public class CountCache { c2]h.G83
public static LinkedList list=new LinkedList(); S$a.8Xh
/** Creates a new instance of CountCache */ ET%F+
public CountCache() {} R''2o_F6
public static void add(CountBean cb){ )r(e\_n
if(cb!=null){ (@=h(u .
list.add(cb); %UG|R:
} 8k_hX^
} Un&rP70
} Dw,LB>Eq,
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CountControl.java cmY `$=
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/* V5 Gy|X
* CountThread.java 8<J3Xe
* PK&X |
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* Created on 2007年1月1日, 下午4:57 ]1I-e2Q-J
* >A}ra ^gU
* To change this template, choose Tools | Options and locate the template under ?q y*`
* the Source Creation and Management node. Right-click the template and choose }|RL6p-/'
* Open. You can then make changes to the template in the Source Editor. m&[(xVM
*/ (v$
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package com.tot.count; _P%PjFQ)
import tot.db.DBUtils; \7e4t
import java.sql.*; KYq<n& s
/** IU"8.(;o
* ly@%1
* @author x6vkd%fCj
*/ c]|Tg9AW
public class CountControl{ ojVN-*5
private static long lastExecuteTime=0;//上次更新时间 Ij9=J1c4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v7D0E[)~
/** Creates a new instance of CountThread */ VS65SxHA
public CountControl() {} BU|m{YZ$
public synchronized void executeUpdate(){ /)4Q%Zp
Connection conn=null; {&FOa'bP
PreparedStatement ps=null; r>rL[`p(2
try{ <t"fL
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conn = DBUtils.getConnection(); ?DY6V;&F@f
conn.setAutoCommit(false); 'G`xD3 E3,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yz)Nco]
for(int i=0;i<CountCache.list.size();i++){ ler$HA%F]
CountBean cb=(CountBean)CountCache.list.getFirst(); W~s:SN
CountCache.list.removeFirst(); dE3M
ps.setInt(1, cb.getCountId()); y4H/CH$%
ps.executeUpdate();⑴ `*i:z'
//ps.addBatch();⑵ 8rNf4]5@X(
} -.Zy(
//int [] counts = ps.executeBatch();⑶ y-Lm^GW4
conn.commit(); J?jxD/9Yb
}catch(Exception e){ _J,*0~O$
e.printStackTrace(); ?}C8_I|4~
} finally{ GxE`z6%[
try{ q^L"@Q5;
if(ps!=null) { +hs:W'`%
ps.clearParameters(); +KIBbXF7
ps.close(); _9S"rH[
ps=null; -@~4: o
} iZ(JwY
}catch(SQLException e){} Ol;"}3*Z*
DBUtils.closeConnection(conn); X& XD2o"rt
} B~ j3!?
} !VHw*fL|r
public long getLast(){ ~b[5}_L=>
return lastExecuteTime; hl8oE5MU
} >&T J
public void run(){ $4]4G=o
long now = System.currentTimeMillis(); xg;F};}5$
if ((now - lastExecuteTime) > executeSep) { \^lDd~MWG
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8boiJku`
//System.out.print(" now:"+now+"\n"); WGUd@lC~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HLqDI lL
lastExecuteTime=now; lEw!H^O4
executeUpdate(); |w>d]eA5
} '1Ex{$Yk
else{ yEVnG`
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _gpf9ad
} Jb)xzUhES
}
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} oYWHO<b
//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 U:|:Y=O?Q
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类写好了,下面是在JSP中如下调用。 On,z#A
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<% NkAu<>
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CountBean cb=new CountBean(); LfvRH?<W
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `U>]*D68
CountCache.add(cb); -8SZ}J
out.print(CountCache.list.size()+"<br>"); l?HC-_Pbh
CountControl c=new CountControl(); u!McPM8Yk
c.run(); <JW%h :\t
out.print(CountCache.list.size()+"<br>"); 7&Ie3[Rm_3
%>