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: wRn]
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CountBean.java #Jv|zf5Z
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/* s
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* CountData.java 5:%xuJD
* cF9bSY_Eh
* Created on 2007年1月1日, 下午4:44 W3s>+yU
* tCAh?nR
* To change this template, choose Tools | Options and locate the template under DIH|6R
* the Source Creation and Management node. Right-click the template and choose =7@N'xX
* Open. You can then make changes to the template in the Source Editor. {ZiJnJX
*/ *2ZX*w37
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package com.tot.count; w yP|#Z\
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/** n`Pwo&
* yrOWC
* @author ?!=yp#
*/
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public class CountBean { FS7 _ldD
private String countType; >J+'hm@
int countId; C?jk#T
/** Creates a new instance of CountData */ >58N P1[k
public CountBean() {} j+He8w-4
public void setCountType(String countTypes){ <rZ(B>$
this.countType=countTypes; K' xN>qc
} 9P;}P!W
public void setCountId(int countIds){ xT7JGQ[|
this.countId=countIds; { O+d7,C
}
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public String getCountType(){ Gf'qPLK0
return countType; jnfktDV'
} Atc<xp
public int getCountId(){ :ulOG{z
return countId; ]n9o=^q/
} A)9OkLrc
} o!W
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CountCache.java #@s[!4)_I
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/* e P]L
* CountCache.java Y;$wD9W
* {"T$jV:GB
* Created on 2007年1月1日, 下午5:01 tHAr9
* P;_}nbB
* To change this template, choose Tools | Options and locate the template under t*Hr(|.
* the Source Creation and Management node. Right-click the template and choose .J0s_[
* Open. You can then make changes to the template in the Source Editor. $+CKy>
*/ hTZ&
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package com.tot.count; 7kX;|NA1
import java.util.*; UnSi= uj
/** XpWcf ([
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* @author coa+@g,w7#
*/ t5:
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public class CountCache { d:C|laZHn
public static LinkedList list=new LinkedList(); 1t&LNIc|^
/** Creates a new instance of CountCache */ a6\0XVU
public CountCache() {} ~6YTm6o
public static void add(CountBean cb){ cu{c:z~
if(cb!=null){ m'{gO9V
list.add(cb); /Kcp9Qx
} e
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} |q0F*\z3
} &QHZ]2%U
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CountControl.java D%[yAr;r
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/* ^n Gj 7b
* CountThread.java Hw"LoVh
* <'WS -P%U
* Created on 2007年1月1日, 下午4:57 M_
* KA
* S7i,oP7
* To change this template, choose Tools | Options and locate the template under @">^2
* the Source Creation and Management node. Right-click the template and choose ?'>pfU
* Open. You can then make changes to the template in the Source Editor. 'cp1I&>
*/ N_jpCCG~
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package com.tot.count; N@}5Fnk-
import tot.db.DBUtils; 90g=&O5@O
import java.sql.*; 1eod;^AP9
/** XT2:XWI8
* Fpe>|"&
* @author Tvp ~~Dk
*/ }6S~"<Ym
public class CountControl{ 2bIP.M2Fs
private static long lastExecuteTime=0;//上次更新时间 bhk:Szqz
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 d\eTyN'rA
/** Creates a new instance of CountThread */ tUOqF
public CountControl() {} a -[:RJW
public synchronized void executeUpdate(){ !*I0}I
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Connection conn=null; \%],pZsA ~
PreparedStatement ps=null; tW$Di*h
try{ dWKjVf
conn = DBUtils.getConnection(); .VD:FFkW
conn.setAutoCommit(false); 9):h
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); oU|yBs1
for(int i=0;i<CountCache.list.size();i++){ :8(
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CountBean cb=(CountBean)CountCache.list.getFirst(); JSp V2c5Q
CountCache.list.removeFirst(); J}zN]|bz
ps.setInt(1, cb.getCountId()); \S5YS2,P
ps.executeUpdate();⑴ lftT55Tki
//ps.addBatch();⑵ z5njblUz
} dd?ZQ:n
//int [] counts = ps.executeBatch();⑶ _P].Z8
conn.commit(); IA6,P>}N
}catch(Exception e){ "}|&eBH^<
e.printStackTrace(); b=87k
} finally{ fx74h{3u
try{ c]Z@L~WW
if(ps!=null) { 4Su|aWL-
ps.clearParameters(); 2)-V\:;js
ps.close(); V1l9T_;f
ps=null; K>a@AXC
} bM@8[&ta
}catch(SQLException e){} Ca]V%g(
DBUtils.closeConnection(conn); Aq]*$s2\G
} v%
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} vV$6fvS
public long getLast(){ aG*Mj;J
return lastExecuteTime; +uqP:z
} F/
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public void run(){ pw,
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long now = System.currentTimeMillis(); :Vnus
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if ((now - lastExecuteTime) > executeSep) { T[(4z@d`5
//System.out.print("lastExecuteTime:"+lastExecuteTime); :qAF}|6
//System.out.print(" now:"+now+"\n"); BN]{o(EB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7 'B9z/
lastExecuteTime=now; }57d3s
executeUpdate(); bVgmjt2&>
} QKP@+E_U
else{ E9N.b.Q)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +M s`C)f
} !'5t(Zw5
} (@(rz/H
} LX%UkfA9
//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 T GuvyY
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类写好了,下面是在JSP中如下调用。 L"x9O'U
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<% 1RU+d.&D
CountBean cb=new CountBean(); HYcwtw6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i_'u:P<t
CountCache.add(cb); KQulz
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); 4*9WxhJ ]0
c.run(); @ak3ZNor
out.print(CountCache.list.size()+"<br>"); 1cdX0[sN
%>