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: &1{k^>oz
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CountBean.java Zy%Z]dF
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/* d/&|%Z
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* CountData.java }}_uN-m
* >C[1@-]G%7
* Created on 2007年1月1日, 下午4:44 w!RH*S
* a:}"\>Aj
* To change this template, choose Tools | Options and locate the template under l/^-:RRNKi
* the Source Creation and Management node. Right-click the template and choose q@9i3*q;
* Open. You can then make changes to the template in the Source Editor. nS4S[|w"
*/ G,-OH-M!
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package com.tot.count; 5KR|p Fq
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/** @E2nF|N
* ]Qr8 wa>Z
* @author @W8}N|jek
*/ JZzf,G:
public class CountBean { m!60.
private String countType; b<AE}UK
int countId; hhAC@EGG
/** Creates a new instance of CountData */ l|A8AuO*?
public CountBean() {} ]ECZU
public void setCountType(String countTypes){ #\BI-zt
this.countType=countTypes; +3>/,w(x
} qk,y |7p
public void setCountId(int countIds){ \STvBI?
this.countId=countIds; "NH+qQhs
} 8$U ZL
public String getCountType(){ /'6[*]IZP
return countType; JK"uj%
} YO$b#
public int getCountId(){ 3b@1Zahz
return countId; +A ?+G
} G@EjWZQ
} G!Oq>7
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CountCache.java up3<=u{>
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/* }|"*"kxi!
* CountCache.java u6I0<i_KZ
* )|R0_9CLV
* Created on 2007年1月1日, 下午5:01 p]|ME
* C%?D E@k
* To change this template, choose Tools | Options and locate the template under yn":!4U1
* the Source Creation and Management node. Right-click the template and choose a 8hv .43
* Open. You can then make changes to the template in the Source Editor. MQH8Q$5D
*/ k,iV$,[TF
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package com.tot.count; IA 9v1:>
import java.util.*; YZ:'8<
/** X:-bAu}D
* IcA\3j
* @author 2j/1@Z1j=
*/ UFAMbI
public class CountCache { K^&
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public static LinkedList list=new LinkedList(); hOL y*%
/** Creates a new instance of CountCache */ WlRZ|.
public CountCache() {} 2N8sq(LK{
public static void add(CountBean cb){ 6dR-HhF
if(cb!=null){ HD8"=7zJk
list.add(cb); (=tF2YBV
} M=
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} 9k+&fyy
} t k/K0u
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CountControl.java -f;j1bQ
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/* )"c]FI[}
* CountThread.java xBE
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* Q~Sv2
* Created on 2007年1月1日, 下午4:57 07LL)v~
* iI@Gyq=
* To change this template, choose Tools | Options and locate the template under z2nUul(2
* the Source Creation and Management node. Right-click the template and choose 0O['-x
* Open. You can then make changes to the template in the Source Editor. Yx}"> ;\
*/ ~SR(K{nf#.
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package com.tot.count; lF}$`6
import tot.db.DBUtils; o!l3.5m2d
import java.sql.*; &(uF&-PwO4
/** WP@JrnxO\`
* j
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* @author ",aT<lw.
*/ b6WC@j`*T
public class CountControl{ R!V5-0%
private static long lastExecuteTime=0;//上次更新时间 }2BH_
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 y%IG:kZ,
/** Creates a new instance of CountThread */ WP%{{zR$
public CountControl() {} 8NAWA3^B
public synchronized void executeUpdate(){ K7[AiU_I
Connection conn=null; #-gGsj;F
PreparedStatement ps=null; !AD0-fZ
try{ ej"o?1l@
conn = DBUtils.getConnection(); vA"`0
conn.setAutoCommit(false); gM;)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b!^M}s6
for(int i=0;i<CountCache.list.size();i++){ s7UhC.>'@
CountBean cb=(CountBean)CountCache.list.getFirst(); ]lB3qEn<
CountCache.list.removeFirst(); I"F
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ps.setInt(1, cb.getCountId()); p'%: M
ps.executeUpdate();⑴ %];h|[ax]
//ps.addBatch();⑵ kuTq8p2E
} m_E[bDON
//int [] counts = ps.executeBatch();⑶ DQ n`@
conn.commit(); !}L~@[v,uL
}catch(Exception e){ ].k+Nzf_
e.printStackTrace(); <>T&ab@dE(
} finally{ }o!#_N0T
try{ >TlW]st
if(ps!=null) { n2jvXLJq
ps.clearParameters(); Mg a@JA"
ps.close(); Ha=_u+@
ps=null; =YXe1$ $
} 4[LLnF--
}catch(SQLException e){} {;Y 89&*R
DBUtils.closeConnection(conn); H4}%;m%
} !y
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} [w+h-q
public long getLast(){ 7g A08M[O
return lastExecuteTime; &*G5J7%w
} /i-xX*
public void run(){ Sc4obcw%
long now = System.currentTimeMillis(); 3wN?|N
if ((now - lastExecuteTime) > executeSep) { nOAJ9
//System.out.print("lastExecuteTime:"+lastExecuteTime); G%P>Ag
//System.out.print(" now:"+now+"\n"); E-yT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); jb|mip@`
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lastExecuteTime=now; &dhcKO<4
executeUpdate(); [K cki+
} Ow
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else{ w24{_ N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); KP[NuXA`
} e/"yGQu
} c;:">NR
} DS#cm3
//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 YG0Px Zmi
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类写好了,下面是在JSP中如下调用。 @~m=5C
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<% KQG-2oW
CountBean cb=new CountBean(); H~A"C'P3#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); R)0N0gH
CountCache.add(cb); [##`Um
out.print(CountCache.list.size()+"<br>"); 8YuJ8KC
CountControl c=new CountControl(); L'zE<3O'3
c.run(); bA}AD`5
out.print(CountCache.list.size()+"<br>"); J|VK P7
%>