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: 1E8H%2$ V
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CountBean.java ]@X{dc
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/* r6`\d k
* CountData.java i&`!|X-=R
* GQN98Y+h
* Created on 2007年1月1日, 下午4:44 lhqQCV
* XRa(sXA3
* To change this template, choose Tools | Options and locate the template under pW\z\o/2
* the Source Creation and Management node. Right-click the template and choose DVI7]+=nV
* Open. You can then make changes to the template in the Source Editor. ITyzs4"VV
*/ XHs d-
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package com.tot.count; :peqr!I+K
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/** ^7u X$
* Kax#OYLpg
* @author G0}Dq MTi
*/ eC ~jgB
public class CountBean { U98_M)-%&
private String countType; ->\N_|_
int countId; Ap%O~wA'
/** Creates a new instance of CountData */ fk>l{W}e)
public CountBean() {} Dl%?OG<
public void setCountType(String countTypes){ 9x=3W?K:,
this.countType=countTypes; S'o ]=&
} .Y1bY :=
public void setCountId(int countIds){ 2FGx _Y
this.countId=countIds; $uCiXDKCq
} XaW4C-D&
public String getCountType(){ bGN
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return countType; OX+hZ<y
} 6lsL^]7
public int getCountId(){ *>k!hq;j
return countId; Q',m{;;
}
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CountCache.java c3] C:t+
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/* I}+;ME|<2
* CountCache.java $jG4pPG
* b3\B8:XFo|
* Created on 2007年1月1日, 下午5:01 xP{-19s1]
* !hCS#'
* To change this template, choose Tools | Options and locate the template under ^agj4$
* the Source Creation and Management node. Right-click the template and choose H`-=?t
* Open. You can then make changes to the template in the Source Editor. MiJ6 n[iv
*/ K\P!a@>1
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package com.tot.count; Seda }
import java.util.*; Uky9zGa
/** uEx9-,!
* -`7$Qu2
* @author !\;:36B#6
*/ VD$Eb
public class CountCache { mV?&%>*(f
public static LinkedList list=new LinkedList(); rJQ=9qn\
/** Creates a new instance of CountCache */ Jx$iwu
public CountCache() {} .x}gg\
public static void add(CountBean cb){ ;,XyN+2H
if(cb!=null){ ;/'|WLI9
list.add(cb); QHzgy?
} z(me@P!D~
} >)Gd:636+
} +`.,| |Mq
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CountControl.java x=]S.XI
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/* 5M:D?9E+
* CountThread.java ES}. xZ#~
* \}JrFc%O
* Created on 2007年1月1日, 下午4:57 #Qh>z%Mn^3
* dl0FQNz8@B
* To change this template, choose Tools | Options and locate the template under 0xCz'mJ
* the Source Creation and Management node. Right-click the template and choose q8xd*--#
* Open. You can then make changes to the template in the Source Editor. hj!+HHYSk
*/ b5pMq$UVL
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package com.tot.count; !][F
import tot.db.DBUtils; )(m0cP{7
import java.sql.*; 5mgHlsDzu
/** y-B=W]E
* *C6 D3y
* @author :#u}.G
*/ r_U>VT^E:
public class CountControl{ uS<_4A;sD,
private static long lastExecuteTime=0;//上次更新时间 $^_|j1z#i
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p|qyTeg
/** Creates a new instance of CountThread */ CzVmNy)kl
public CountControl() {} KX3KM!*
public synchronized void executeUpdate(){ `8:K[gp
Connection conn=null; $`ztiVu3
PreparedStatement ps=null; ?6P.b6m}0
try{ S1bAu
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conn = DBUtils.getConnection(); #NN ewzC<*
conn.setAutoCommit(false); OBOwz4<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); T_;]fPajjD
for(int i=0;i<CountCache.list.size();i++){ DlTR|(AL
CountBean cb=(CountBean)CountCache.list.getFirst(); w?LrJ37u
CountCache.list.removeFirst(); *:hyY!x
ps.setInt(1, cb.getCountId()); " aq'R(/`c
ps.executeUpdate();⑴ p&N#_dmlH
//ps.addBatch();⑵ oyx^a9
} Br5o7(AE
//int [] counts = ps.executeBatch();⑶ TDNf)Mm
conn.commit(); '6-$Xq0^E
}catch(Exception e){ o3N] `xD'
e.printStackTrace(); \we\0@v
} finally{ ?&X6:KJQ
try{ 0CAa^Q^w
if(ps!=null) { qp p/8M
ps.clearParameters(); M \D]ml~
ps.close(); h#qN+qt}
ps=null; OqUr9?+
} jQh^WmN
}catch(SQLException e){} {Wv%zA*8
DBUtils.closeConnection(conn); >v+jh(^
} Y`GOER
} d=3'?l`
public long getLast(){ _yH`t[
return lastExecuteTime; }-DE`c
} izZ=d5+K
public void run(){ D'_Bz8H!p
long now = System.currentTimeMillis(); 4Ysb5m)u
if ((now - lastExecuteTime) > executeSep) { 3x@<Z68S
//System.out.print("lastExecuteTime:"+lastExecuteTime); )9v`f9X){
//System.out.print(" now:"+now+"\n"); `BY&>WY[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uQqWew8l+
lastExecuteTime=now; Pbu{'y3J
executeUpdate(); v?:: |{
} kH948<fk3
else{ 9X}I>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); G"dS+,Q
} J
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} jd-glE,Y/
} K^[#]+nQ
//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 {+.r5py
|L6&Gf]#5
类写好了,下面是在JSP中如下调用。 S :bC[}
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<% _5Bcwa/
CountBean cb=new CountBean(); &^".2)zU
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O;9?(:_
CountCache.add(cb); )_7>nuQ6
out.print(CountCache.list.size()+"<br>"); u1^wDc*xg
CountControl c=new CountControl(); {QAv~S>4
c.run(); )cJ#-M2
out.print(CountCache.list.size()+"<br>"); 7[#yu 2
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